JP2013174310A - Device and method for controlling transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To restrain the deterioration of the durability of a transmission caused by changeover from a neutral position in the duration of vehicle traveling to a forward traveling position.SOLUTION: In the duration of vehicle traveling in a state that a neutral position is selected and all clutches or the like of an automatic transmission are released, a shift position SP is shifted to a forward traveling position (S110) from the neutral position, and when it is determined that there is a risk that there may arise an over-rotation state of a sun gear of a Ravigneaux type planetary gear mechanism constituting the automatic transmission accompanied by engagement with the clutch (first element) which s firstly engaged out of the two clutches corresponding to a determination objective gear change stage Gd (S150), the engagement of the two clutches corresponding to the determination objective gear change stage Gd being a tar gear change stage Gtag can be delayed (S160-S180, S205, S210).

Description

  The present invention is mounted on a vehicle and selectively engages a plurality of engagement elements that are operated by hydraulic pressure from a hydraulic control device to form a plurality of shift stages, and power applied from a prime mover to an input shaft. TECHNICAL FIELD The present invention relates to a transmission control device and a control method for transmitting a motor to an output shaft.

  Conventionally, as a control device for an automatic transmission for a vehicle having a plurality of engagement elements and a hydraulic circuit, when a neutral position is selected as a shift position by a driver, all of the plurality of engagement elements are controlled to be in a released state. Is known (see, for example, Patent Document 1). When the shift position is switched from the neutral position to the forward travel position while the vehicle is traveling, the control device reduces the output torque of the drive source from the torque corresponding to the accelerator opening, and the target shift speed corresponding to the vehicle speed. Is formed by engaging at least two engaging elements, the first engaging element that is a part of the two or more engaging elements is replaced with the remaining second engaging elements. Control to engage with priority over the element.

JP 2009-299878 A

  However, even if the shift control as in the conventional example is performed, the second engagement element is engaged after the first engagement element is engaged depending on the target shift stage after switching to the forward travel position. In the meantime, any of the rotating elements constituting the automatic transmission may rotate at a rotational speed exceeding the allowable rotational speed, which may adversely affect the durability of the automatic transmission.

  In view of the above, the main object of the present invention is to suppress deterioration in the durability of the transmission due to switching from the neutral position to the forward travel position during vehicle travel.

  The transmission control apparatus and control method according to the present invention employ the following means in order to achieve the main object.

A transmission control apparatus according to the present invention includes:
A plurality of shift elements are formed by selectively engaging a plurality of engagement elements that are mounted on a vehicle and operated by hydraulic pressure from a hydraulic control device, and the power applied from the prime mover to the input member is used as an output member. In the transmission control device for transmission,
Shift position determination means for determining whether or not the shift position has been switched from the neutral position to the forward travel position during travel of the vehicle in a state in which a neutral position is selected and all of the engagement elements are released; ,
The shift position determining means determines that the shift position has been switched from the neutral position to the forward travel position, and at least two of the engagements to form a target gear position after switching to the forward travel position. Engagement control means for controlling the hydraulic control device so that the at least two engagement elements are engaged in a predetermined order when the combination element is to be engaged;
When the shift position determination means determines that the shift position has been switched from the neutral position to the forward travel position, the first engagement of the at least two engagement elements corresponding to the target shift stage is performed. Over-rotation for determining whether there is a possibility of causing an over-rotation state in which any of the rotation elements constituting the transmission rotates at a rotation speed exceeding an allowable rotation speed with the engagement of the first element to be combined Determination means,
The engagement control means delays the engagement of the at least two engagement elements corresponding to the target shift speed when it is determined by the over-rotation determination means that the over-rotation state is likely to occur. It is characterized by.

  The transmission control apparatus determines that the shift position is switched from the neutral position to the forward travel position while the vehicle is traveling in a state where the neutral position is selected and all of the engagement elements are released, and Any rotation element constituting the transmission is allowed in accordance with the engagement of the first element to be engaged first among the at least two engagement elements corresponding to the target shift speed after switching to the forward travel position. When it is determined that there is a possibility of causing an over-rotation state that rotates at a rotation speed exceeding the rotation speed, the engagement of at least two engagement elements corresponding to the target shift speed is delayed. As described above, when there is a possibility of over-rotation when forming the target shift speed after switching from the neutral position during vehicle travel to the forward travel position, at least two engagement elements corresponding to the target shift speed, that is, first By delaying the start of engagement of the first element to be engaged, it is possible to wait for a decrease in the rotational speed of the prime mover or the input member. As a result, any rotation element that constitutes the transmission with the engagement of the first element does not rotate at a rotational speed that exceeds the allowable rotational speed, so that the neutral position during traveling of the vehicle is changed to the forward traveling position. It becomes possible to suppress the deterioration of the durability of the transmission due to the switching. The engagement element may be a friction engagement element or a meshing engagement element.

  In addition, when it is determined by the over-rotation determination unit that the over-rotation state is likely to be caused, the engagement control unit is configured to correspond to the target shift stage when the possibility of causing the over-rotation state is eliminated. The hydraulic control device may be controlled so that at least two of the engaging elements are engaged in the order. As a result, it is possible to more reliably suppress any of the rotating elements constituting the transmission from rotating at a rotational speed that exceeds the allowable rotational speed in association with the engagement of the first element.

  Further, the engagement control means, when it is determined that there is a possibility that the over-rotation state is likely to be caused by the over-rotation determination means, and when there is no possibility that the over-rotation state is caused after a predetermined time has passed, The hydraulic control device may be controlled so that at least two of the engagement elements corresponding to the second target shift speed higher than the target shift speed are engaged in a predetermined order. . As a result, the shift position is set to the neutral position while the vehicle is running, while preventing any of the rotating elements constituting the transmission from rotating at a rotational speed that exceeds the allowable rotational speed as the first element is engaged. Accordingly, it is possible to suppress a decrease in the shift response when the vehicle is switched from the forward travel position to the forward travel position. When the second target shift speed higher than the target shift speed is formed, the driving force transmitted to the output member is smaller than when the initial target shift speed is formed. Can stabilize the behavior and improve drivability.

  Further, when the first element corresponds to the second target shift speed, the engagement control means is configured to select the first of the at least two engagement elements corresponding to the second target shift speed. The hydraulic control device may be controlled so that engagement elements other than one element are engaged first. Accordingly, when the second target shift speed is formed, it is possible to prevent any rotation element constituting the transmission from rotating at a rotational speed exceeding the allowable rotational speed in association with the engagement of the first element. Become.

  Further, the engagement control means transmits a command value for reducing the rotational speed of the prime mover to the control device of the prime mover when it is judged by the over revolution judgment means that there is a risk of causing the overspeed state. You may do. This delays the engagement of at least two engagement elements corresponding to the target gear position even when the accelerator pedal is depressed by the driver of the vehicle when switching from the neutral position during traveling to the forward traveling position. Since the rotational speed of the prime mover and the input member can be reduced during the operation, any rotational element constituting the transmission rotates at a rotational speed exceeding the allowable rotational speed in accordance with the engagement of the first element. This can be suppressed very well.

  The engagement control means limits the output torque of the prime mover so that heat generation of the engagement elements is suppressed when the at least two engagement elements corresponding to the target shift speed are engaged. The command value may be transmitted to the controller of the prime mover, and the command value is determined so as to greatly reduce the output torque of the prime mover than the second command value. May be. As a result, while the engagement of at least two engagement elements corresponding to the target gear stage is delayed, the rotational speed of the prime mover and the input member can be reduced more quickly and the at least two engagement elements can be engaged. When combining them, it is possible to suppress the heat generation of the engagement element while securing the output torque from the prime mover and suppressing the deterioration of the running performance of the vehicle.

  Further, the over-rotation determining means may determine whether or not there is a possibility of causing the over-rotation state based on a rotation speed of the input member and a rotation speed of the output member. Thereby, it becomes possible to determine more appropriately whether there is a possibility of causing an over-rotation state.

A transmission control method according to the present invention includes:
A plurality of shift elements are formed by selectively engaging a plurality of engagement elements that are mounted on a vehicle and operated by hydraulic pressure from a hydraulic control device, and the power applied from the prime mover to the input member is used as an output member. In a control method of a transmission for transmission,
(A) determining whether or not the shift position has been switched from the neutral position to the forward travel position during travel of the vehicle with the neutral position selected and all of the engagement elements released; ,
(B) when it is determined in step (a) that the shift position has been switched from the neutral position to the forward travel position, a target gear position of the transmission is set;
(C) When at least two of the engagement elements are to be engaged to form the target gear set in step (b), the first engagement of the at least two engagement elements Determining whether there is a possibility of causing an over-rotation state in which any of the rotating elements constituting the transmission rotates at a rotation speed exceeding an allowable rotation speed in accordance with the engagement of the first element to be performed;
(D) controlling the hydraulic control device so that at least two engaging elements corresponding to the target gear set in step (b) are engaged in a predetermined order; and step (c) Delaying the engagement of the at least two engagement elements corresponding to the target shift stage when it is determined that there is a risk of causing the overspeed state at
Is included.

  According to this method, the vehicle travels forward from the neutral position during traveling of the vehicle so that any of the rotating elements constituting the transmission does not rotate at a rotational speed exceeding the permissible rotational speed as the first element is engaged. It becomes possible to suppress the deterioration of the durability of the transmission due to the switching to the position.

It is a schematic block diagram of the motor vehicle 10 carrying the power transmission device 20 containing the automatic transmission 25 controlled by the control apparatus by this invention. FIG. 2 is a schematic configuration diagram showing a power transmission device 20. 3 is an operation table showing a relationship between each gear position of the automatic transmission 25 and operation states of clutches and brakes. 3 is a speed diagram illustrating the relationship of rotational speeds between rotating elements constituting the automatic transmission 25. FIG. 2 is a system diagram showing a hydraulic control device 50. FIG. It is a flowchart which shows an example of the ND shift control routine performed by transmission ECU21 which is a control apparatus by this invention. It is a time chart for demonstrating the target gear stage formation control in step S200 of FIG. FIG. 6 is an explanatory diagram illustrating an overspeed range or the like defined by a combination of an input rotation speed Nin that causes an overspeed state of the sun gear 36b of the automatic transmission 25 and a rotation speed Nout of the output shaft 27. 4 is a time chart for explaining a procedure for forming an engagement delay stage Gd when a shift position is switched from a neutral position to a forward travel position such as a drive position while the automobile 10 is traveling.

  Next, embodiments of the present invention will be described using examples.

  FIG. 1 is a schematic configuration diagram of an automobile 10 equipped with a power transmission device 20 including an automatic transmission 25 controlled by a control device according to the present invention. An automobile 10 shown in the figure includes an engine (internal combustion engine) 12 as a prime mover that outputs power by explosion combustion of a mixture of hydrocarbon fuel such as gasoline and light oil and air, and an engine electronic for controlling the engine 12. A control unit (hereinafter referred to as “engine ECU”) 14, a brake electronic control unit (hereinafter referred to as “brake ECU”) 16 for controlling an electronically controlled hydraulic brake unit (not shown) 16, and an engine 12 are connected to the engine 12. Including a power transmission device 20 that transmits power from the left and right drive wheels DW. The power transmission device 20 includes a transmission case 22, a fluid transmission device (torque converter) 23, an automatic transmission 25, a hydraulic control device 50, and a shift electronic control unit (hereinafter, “ 21) and the like.

  The engine ECU 14 is configured as a microcomputer centering on a CPU (not shown). In addition to the CPU, a ROM that stores various programs, a RAM that temporarily stores data, an input / output port, and a communication port (all not shown). Etc.). As shown in FIG. 1, the engine ECU 14 includes an accelerator opening Acc from an accelerator pedal position sensor 92 that detects a depression amount (operation amount) of an accelerator pedal 91, a vehicle speed V from a vehicle speed sensor 97, and rotation of a crankshaft. Signals from various sensors such as a crankshaft position sensor (not shown) for detecting the position, signals from the brake ECU 16 and the shift ECU 21 and the like are input, and the engine ECU 14 is based on these signals, and an electronically controlled throttle (not shown). Controls valves, fuel injection valves and spark plugs. Further, the engine ECU 14 calculates the rotational speed Ne of the engine 12 based on the rotational position of the crankshaft detected by the crankshaft position sensor, and for example, the intake of the engine 12 detected by the rotational speed Ne or an air flow meter (not shown). An estimated engine torque Test, which is an estimated value of the torque output from the engine 12, is calculated based on the air amount, the throttle opening THR of the throttle valve, and a predetermined map or calculation formula.

  The brake ECU 16 is also configured as a microcomputer centering on a CPU (not shown). In addition to the CPU, a ROM for storing various programs, a RAM for temporarily storing data, an input / output port and a communication port (none of which are shown). ) Etc. As shown in FIG. 1, the brake ECU 16 receives the master cylinder pressure Pmc detected by the master cylinder pressure sensor 94 when the brake pedal 93 is depressed, the vehicle speed V from the vehicle speed sensor 97, various sensors (not shown), and the like. Signals, signals from the engine ECU 14 and the shift ECU 21 and the like are input, and the brake ECU 16 controls a brake actuator (hydraulic actuator) (not shown) based on these signals.

  The speed change ECU 21 is also configured as a microcomputer centered on a CPU (not shown). In addition to the CPU, a ROM that stores various programs, a RAM that temporarily stores data, an input / output port, and a communication port (all not shown). ) Etc. As shown in FIG. 1, the shift ECU 21 includes an accelerator opening Acc from the accelerator pedal position sensor 92, a shift position SP from the shift position sensor 96 that detects the operation position of the shift lever 95, and a vehicle speed from the vehicle speed sensor 97. V, the rotational speed sensor 98 for detecting the input rotational speed of the automatic transmission 25 (the rotational speed of the turbine runner 23b or the input shaft 26 of the automatic transmission 25) Nin, and the oil temperature Toil of the hydraulic control device 50. Signals from various sensors such as the oil temperature sensor 99, signals from the engine ECU 14 and the brake ECU 16, and the like are input, and the transmission ECU 21 receives the fluid transmission device 23 and the automatic transmission 25, that is, the hydraulic control device 50 based on these signals. To control. The shift position SP that can be set by the shift lever 95 includes a parking position (P position), a reverse position (R position), a neutral position (N position), a forward drive position (D position), and a sports position ( S position) and the like.

  As shown in FIG. 2, the fluid transmission device 23 of the power transmission device 20 is connected to an input-side pump impeller 23 a connected to the crankshaft of the engine 12 and an input shaft (input member) 26 of the automatic transmission 25. The output side turbine runner 23b and the lockup clutch 23c are included. The oil pump 24 is configured as a gear pump including a pump assembly including a pump body and a pump cover, and an external gear connected to the pump impeller 23a of the fluid transmission device 23 via a hub. When the external gear is rotated by the power from the engine 12, the hydraulic oil (ATF) stored in the oil pan (not shown) is sucked by the oil pump 24 and is pumped to the hydraulic control device 50.

  The automatic transmission 25 is configured as a six-speed transmission, and as shown in FIG. 2, a single pinion planetary gear mechanism 30, a Ravigneaux planetary gear mechanism 35, and an input side to an output side. Three clutches C1, C2 and C3, two brakes B1 and B2 and a one-way clutch F1 are included as friction engagement elements for changing the power transmission path. The single pinion planetary gear mechanism 30 includes a sun gear 31 that is an external gear fixed to the transmission case 22, and an internal gear that is disposed concentrically with the sun gear 31 and connected to an input shaft (input member) 26. A ring gear 32, a plurality of pinion gears 33 that mesh with the sun gear 31 and mesh with the ring gear 32, and a carrier 34 that holds the plurality of pinion gears 33 so as to rotate and revolve.

  The Ravigneaux planetary gear mechanism 35 meshes with two sun gears 36a and 36b that are external gears, a ring gear 37 that is an internal gear fixed to the output shaft (output member) 27 of the automatic transmission 25, and the sun gear 36a. A plurality of short pinion gears 38a, a plurality of long pinion gears 38b meshed with the sun gear 36b and the plurality of short pinion gears 38a and meshed with the ring gear 37, and a plurality of short pinion gears 38a and a plurality of long pinion gears 38b coupled to each other. And a carrier 39 supported by the transmission case 22 via a one-way clutch F1. The output shaft 27 of the automatic transmission 25 is connected to the drive wheels DW via a gear mechanism 28 and a differential mechanism 29.

  The clutch C1 has a hydraulic servo constituted by a piston, a plurality of friction plates, a counter plate, an oil chamber to which hydraulic oil is supplied, and the like, and a carrier 34 of a single pinion planetary gear mechanism 30 and a Ravigneaux planetary gear mechanism 35. This is a multi-plate friction type hydraulic clutch capable of fastening the sun gear 36a and releasing the fastening of both. The clutch C2 has a hydraulic servo composed of a piston, a plurality of friction plates and mating plates, an oil chamber to which hydraulic oil is supplied, and the like, and fastens the input shaft 26 and the carrier 39 of the Ravigneaux planetary gear mechanism 35. At the same time, the multi-plate friction type hydraulic clutch is capable of releasing the fastening of both. The clutch C3 has a hydraulic servo composed of a piston, a plurality of friction plates and mating plates, an oil chamber to which hydraulic oil is supplied, and the like, and a carrier 34 of a single pinion planetary gear mechanism 30 and a Ravigneaux planetary gear mechanism 35. This is a multi-plate friction type hydraulic clutch capable of fastening the sun gear 36b and releasing the fastening of both.

  The brake B1 is configured as a band brake or a multi-plate friction brake including a hydraulic servo, and fixes the sun gear 36b of the Ravigneaux type planetary gear mechanism 35 to the transmission case 22 and releases the fixation of the sun gear 36b to the transmission case 22. It is a hydraulic brake that can. The brake B2 is configured as a band brake or a multi-plate friction brake including a hydraulic servo, and fixes the carrier 39 of the Ravigneaux type planetary gear mechanism 35 to the transmission case 22 and releases the fixing of the carrier 39 to the transmission case 22. It is a hydraulic brake that can.

  These clutches C <b> 1 to C <b> 3 and brakes B <b> 1 and B <b> 2 operate by receiving and supplying hydraulic oil from the hydraulic control device 50. FIG. 3 shows an operation table showing the relationship between the respective speeds of the automatic transmission 25 and the operating states of the clutches C1 to C3 and the brakes B1 and B2. FIG. The speed diagram which illustrates the relationship of the rotational speed in is shown. The automatic transmission 25 sets the clutches C1 to C3 and the brakes B1 and B2 to the states shown in the operation table of FIG. 3 so that the forward 1st to 6th gears and the reverse gear 1 as shown in FIG. And provide.

  FIG. 5 is a system diagram showing the hydraulic control device 50. The hydraulic control device 50 is connected to the above-described oil pump 24 that is driven by the power from the engine 12 and sucks and discharges hydraulic oil from the oil pan, and is requested by the fluid transmission device 23 and the automatic transmission 25. The hydraulic oil is generated and hydraulic oil is supplied to lubricated parts such as various bearings. In addition to the valve body (not shown), the hydraulic control device 50 adjusts the hydraulic oil from the oil pump 24 to generate the line pressure PL and the operation position of the shift lever 95 as shown in FIG. Accordingly, the manual valve 52 for switching the supply destination of the line pressure PL from the primary regulator valve 51, the apply control valve 53, and the line pressure PL as the original pressure supplied from the manual valve 52 (primary regulator valve 51) are regulated. Including a first linear solenoid valve SL1, a second linear solenoid valve SL2, a third linear solenoid valve SL3, a fourth linear solenoid valve SL4, and the like as pressure regulating valves that generate hydraulic pressure to the corresponding clutch and the like.

  The primary regulator valve 51 generates a line pressure using the hydraulic pressure from the linear solenoid valve SLT as a signal pressure. The linear solenoid valve SLT adjusts hydraulic oil from the oil pump 24 side (for example, a modulator valve that regulates the line pressure PL and outputs a constant hydraulic pressure) to respond to an accelerator opening Acc or a throttle valve opening (not shown). The transmission ECU 21 is controlled to output the hydraulic pressure.

  The manual valve 52 is connected to the shift lever 95 in the axially slidable spool, the input port to which the line pressure PL is supplied, the input port of the first to fourth linear solenoid valves SL1 to SL4 and the oil passage. A drive range output port, a reverse range output port, and the like communicating with each other (both not shown). When the forward driving shift position such as the D position or the S position is selected by the driver, the input port is communicated only with the drive range output port by the spool of the manual valve 52, whereby the first to fourth linear solenoids are connected. A line pressure PL as a drive range pressure is supplied to the valves SL1 to SL4. Further, when the R range is selected by the driver, the input port is communicated only with the reverse range output port by the spool of the manual valve 52. Further, when the driver selects the P position or N position, the spool of the manual valve 52 blocks communication between the input port, the drive range output port, and the reverse range output port. Therefore, when the driver selects the P position or the N position, the first to fourth linear solenoid valves SL1 to SL4 are not supplied with the line pressure PL as the drive range pressure via the manual valve 52, and the first Since no hydraulic pressure is generated by the fourth linear solenoid valves SL1 to SL4, the clutches C1 to C3 and the brakes B1 and B2 of the automatic transmission 25 are all released. That is, the manual valve 52 functions as a release means that releases all of the clutches C1 to C3 and the brakes B1 and B2 of the automatic transmission 25 when the driver selects the N position.

  The apply control valve 53 supplies the hydraulic pressure from the third linear solenoid valve SL3 to the clutch C3, the line pressure PL from the primary regulator valve 51 to the clutch C3, and the reverse range output port of the manual valve 52. The second state in which the line pressure PL (reverse range pressure) is supplied to the brake B2, and the line pressure PL (reverse range pressure) from the reverse range output port of the manual valve 52 is supplied to the clutch C3 and the brake B2. The spool valve can selectively form a third state and a fourth state in which the hydraulic pressure from the third linear solenoid valve SL3 is supplied to the brake B2.

  The first linear solenoid valve SL1 is a normally closed linear solenoid valve that adjusts the line pressure PL from the manual valve 52 according to the applied current to generate the hydraulic pressure Psl1 to the clutch C1. The second linear solenoid valve SL2 is a normally closed linear solenoid valve that adjusts the line pressure PL from the manual valve 52 according to the applied current to generate the hydraulic pressure Psl2 to the clutch C2. The third linear solenoid valve SL3 is a normally closed linear solenoid valve that adjusts the line pressure PL from the manual valve 52 according to the applied current to generate the hydraulic pressure Psl3 to the clutch C3 or the brake B2. The fourth linear solenoid valve SL4 is a normally closed linear solenoid valve that adjusts the line pressure PL from the manual valve 52 according to the applied current to generate the hydraulic pressure Psl4 to the brake B1. That is, the hydraulic pressures to the clutches C1 to C3 and the brakes B1 and B2 that are the engagement elements of the automatic transmission 25 are respectively corresponding to the first, second, third, or fourth linear solenoid valves SL1, SL2, SL3, or Directly controlled (set) by SL4.

  The above-described first to fourth linear solenoid valves SL1 to SL4 (currents applied thereto) are controlled by the transmission ECU 21. That is, the speed change ECU 21 changes the speed stage so that a target speed stage Gtag corresponding to the accelerator opening degree Acc (or the opening degree of the throttle valve) and the vehicle speed V acquired from a predetermined speed change diagram (not shown) is formed. A hydraulic pressure command value (engagement pressure command value) to any one of the first to fourth linear solenoid valves SL1 to SL4 corresponding to the clutch or brake (engagement element) engaged with the change of Sets a hydraulic pressure command value (release pressure command value) to any one of the first to fourth linear solenoid valves SL1 to SL4 corresponding to the clutch or brake (release element) released in accordance with the change of the gear position. To do. Further, the shift ECU 21 changes any one or two of the first to fourth linear solenoid valves SL1 to SL4 corresponding to the engaged clutch or brake (engagement element) during the shift stage change or after the shift is completed. Set the hydraulic pressure command value (holding pressure command value) to For this reason, the shift ECU 21 has the above-described hydraulic pressure command value, that is, the engagement pressure command value, the release pressure command value, in cooperation with hardware such as CPU, ROM, and RAM and software such as a control program installed in the ROM. And a shift control module (not shown) for setting the holding pressure command value is constructed as a functional block.

  In the automobile 10, the driver may switch the shift position SP from the forward travel position such as the D position to the N position during the travel. In this case, since the clutches C1 to C3 and the brakes B1 and B2 of the automatic transmission 25 are all released as described above, the shift position SP is subsequently switched from the N position to the forward travel position such as the D position by the driver. Then, the shift ECU 21 controls the hydraulic control device 50 so that the target shift stage Gtag after switching to the forward travel position is formed.

  Next, the shift position SP is changed from the N position to the D position while the vehicle 10 is traveling in a state where the clutch C1 to C3 and the brakes B1 and B2 of the automatic transmission 25 are all released (neutral state). A procedure for forming the target shift stage Gtag when the position is switched to the forward travel position such as a position will be described. FIG. 6 is a flowchart illustrating an example of an ND shift control routine that is executed by the shift ECU 21 while the vehicle 10 is traveling with the N position selected.

  While the vehicle 10 is traveling with the N position selected, the shift ECU 21 (CPU not shown) inputs the shift position SP from the shift position sensor 96 every predetermined time (step S100), and the shift position SP is It is determined whether or not the vehicle has been switched from the N position to the forward travel position such as the D position (step S110). If it is determined in step S110 that the shift position SP remains at the N position, the shift ECU 21 inputs the shift position SP from the shift position sensor 96 at the next input timing (step S100), and again. The determination in step S110 is performed.

  If it is determined in step S110 that the shift position SP has been switched from the N position to the forward travel position such as the D position, the shift ECU 21 determines whether the accelerator opening Acc from the accelerator pedal position sensor 92 or the vehicle speed sensor 97 While inputting the vehicle speed V, the gear position corresponding to the accelerator opening degree Acc and the vehicle speed V acquired from the above-described not-illustrated shift diagram is set as the target gear stage Gtag of the automatic transmission 25 (step S120). Further, the shift ECU 21 determines whether or not the target shift speed Gtag set in step S120 is a determination target shift speed Gd determined in advance in order to determine the overspeed state (step S130). In the embodiment, the determination target gear stage Gd is the fourth speed.

  When it is determined in step S130 that the target gear stage Gtag is any one of the gear speeds other than the determination target gear stage Gd, that is, the first speed to the third speed, the fifth speed, and the sixth speed, the speed change ECU 21 performs step S120. In order to form the target gear stage Gtag set in step S200, target gear stage formation control is executed (step S200). In the target shift speed formation control in step S200, when the target shift speed Gtag is the first speed, the clutch C1 that is engaged when the first speed is formed is engaged as quickly as possible while suppressing the engagement shock or the like. The hydraulic pressure command value Psl1 * for the first linear solenoid valve SL1 corresponding to the clutch C1 is set in accordance with the procedure defined in (1). If the target gear stage Gtag is any one of the second speed, the third speed, the fifth speed, and the sixth speed formed by engaging two clutches or brakes, the target gear stage is formed in step S200. In the control, the hydraulic control device 50 is controlled such that two target clutches and the like are engaged in a predetermined order.

  In the embodiment, the engagement order of the two clutches or the like in the target shift speed formation control in step S200 is the brake B1 or the clutch of the two clutches or the like when the target shift speed Gtag is the second speed or the third speed. C3 is the first element that is engaged first, and the clutch C1 is the second element that is engaged after the first element. Further, when the target gear stage Gtag is the fifth speed or the sixth speed, the clutch C3 corresponding to the element on the shaft on the end portion side (the left end side in the embodiment) of the speed diagram among the two clutches or the like The brake B1 is the first element that is engaged first, and the clutch C2 is the second element that is engaged after the first element.

  With reference to FIG. 7, the target shift speed formation control in step S <b> 200 will be specifically described taking the case where the target shift speed Gtag is the fifth speed as an example. As shown in FIG. 7, when the process of step S200 is executed, the speed change ECU 21 determines whether the shift position SP is switched from the N position to the forward travel position such as the D position, and the engine ECU 14 12 is transmitted (time t0 in FIG. 7). The torque limit value Tlim transmitted to the engine ECU 14 during the execution of the process of step S200 is the second element that is mainly engaged later when engaging the two clutches or the like corresponding to the target gear stage Gtag. This is for reducing the output torque of the engine 12 so that heat generation is suppressed, and here, it is set to a relatively large positive value T1 that is predetermined through experiments and analysis. Thereby, when engaging the two clutches corresponding to the target gear stage Gtag, the output from the engine 12 is secured, and the heat generation of the clutches and the like is suppressed while the deterioration of the running performance of the automobile 10 is suppressed. Is possible. During execution of the process of step S200, instead of the torque limit value Tlim, a target rotational speed for reducing the output torque of the engine 12 is transmitted to the engine ECU 14 so as to suppress the heat generation of the second element or the like. Also good.

  After the transmission of the torque limit value Tlim is started, the transmission ECU 21 compares the estimated engine torque Teest transmitted from, for example, the engine ECU 14 with the torque limit value Tlim (= T1), and the actual output torque Te of the engine 12 becomes the torque limit value. It is determined whether or not Tlim (= T1) or less. When the shift ECU 21 determines that the actual output torque Te has become equal to or less than the torque limit value Tlim (= T1) (time t1 in FIG. 7), as shown by the alternate long and short dash line in FIG. The third linear solenoid valve SL3 corresponding to the clutch C3 is used as the hydraulic pressure (complete engagement pressure) when the clutch C3, which is the first element engaged first among the clutches C3 and C2 corresponding to the speed, is completely engaged. To the hydraulic pressure command value Psl3 *. Thereby, the clutch C3 as the first element is completely engaged within a very short time after the shift position SP is switched from the N position to the forward travel position.

  Further, the speed change ECU 21 determines that the hydraulic pressure actually supplied from the third linear solenoid valve SL3 to the clutch C3 matches the hydraulic pressure command value Psl3 * after a predetermined time has elapsed from the start of setting of the hydraulic pressure command value Psl3 *, for example. Then (time t2 in FIG. 7), setting of the hydraulic pressure command value Psl2 * to the second linear solenoid valve SL2 corresponding to the clutch C2, which is the second element engaged after the first element, is started. The hydraulic pressure command value Psl2 * to the second linear solenoid valve SL2 corresponding to the second element, that is, the clutch C2, is rapidly filled with hydraulic oil in the oil chamber (hydraulic servo) of the clutch C2, as shown by a two-dot chain line in FIG. After being set to a relatively high hydraulic pressure for a predetermined time so as to be (first-filled), it is lowered to a standby pressure corresponding to the input torque of the automatic transmission 25, and then the clutch C2 is applied with a gradient corresponding to the input torque. It is gradually increased to the hydraulic pressure at the time of full engagement.

  As a result, the clutch C2 as the second element is gradually engaged after the clutch C3 as the first element is engaged. The transmission of the torque limit value Tlim to the engine ECU 14 is, for example, a synchronous rotation obtained by multiplying the rotation speed Nout (= vehicle speed V × conversion coefficient) of the output shaft 27 by the gear ratio of the target gear stage Gtag. Continue until it is determined that the speed matches. When the input rotational speed Nin coincides with the synchronous rotational speed obtained by multiplying the rotational speed Nout (= vehicle speed V × conversion coefficient) of the output shaft 27 by the gear ratio of the target gear stage Gtag, the torque limit value Tlim of the engine ECU 14 Transmission is stopped, and the processing of step S200, that is, this routine is ended. After the end of this routine, the transmission ECU 21 controls the hydraulic pressure command value (retained) to any one or two of the first to fourth linear solenoid valves SL1 to SL4 corresponding to the engaged clutch or brake. Pressure command value) is set.

  On the other hand, when it is determined in step S130 that the target shift speed Gtag is the determination target shift speed Gd, that is, the fourth speed, the shift ECU 21 determines the vehicle speed V from the vehicle speed sensor 97 and the input rotation speed Nin from the rotation speed sensor 98. Input (step S140). The transmission ECU 21 then sets the sun gear 36b of the Ravigneaux planetary gear mechanism 35 to a predetermined allowable rotational speed based on a combination of the input rotational speed Nin and the rotational speed Nout of the output shaft 27 obtained by multiplying the vehicle speed V by a conversion factor. It is determined whether or not it is included in a limited rotation range that may be rotated at a rotation speed exceeding (step S150).

  Here, when the clutch C1 is the first element that is first engaged when the fourth speed of the automatic transmission 25 is formed, and the clutch C2 is the second element that is engaged after the first element, the clutch C1 If the clutch C3 other than the clutch C2 and the brake B1 are engaged due to some trouble before the engagement of the clutch C1, as shown in FIG. The second speed or the third speed on the lower speed side than the fourth speed, which is Gtag, is formed, and there is a possibility that the engine 12 may be overrevised. Therefore, in the embodiment, when the target shift speed Gtag is the determination target shift speed Gd, that is, the fourth speed, the first element to which the clutch C2 is first engaged among the clutches C2 and C1 corresponding to the fourth speed. On the other hand, the clutch C1 is the second element that is engaged after the first element.

  However, as shown in FIG. 4, when the automatic transmission 25 is formed at the fourth speed, the clutch C2 is engaged before the clutch C1 with the input rotational speed Nin (the rotational speed Ne of the engine 12) being relatively high. In addition, depending on the rotational speed Nout of the output shaft 27, that is, the vehicle speed V, the rotational speed of the sun gear 36a of the Ravigneaux type planetary gear mechanism 35 may decrease while the rotational speed of the sun gear 36b may increase rapidly. If the sun gear 36b is brought into an overspeed state in which the sun gear 36b rotates at a rotational speed exceeding the allowable rotational speed, the durability of the automatic transmission 25 may be deteriorated.

  Therefore, in the automatic transmission 25 of the embodiment, as shown in FIG. 8, when only the clutch C2 is engaged in the neutral state, the input rotational speed Nin and the output for rotating the sun gear 36b at a rotational speed exceeding the allowable rotational speed are output. By expanding the over-rotation range (hatched portion in FIG. 8) defined by the combination with the rotational speed Nout of the shaft 27 to the low-rotation side with a margin based on experiments and analysis for both the rotational speed Nout and the input rotational speed Nin. A limited rotation area (dot pattern portion in FIG. 8, that is, an area above the boundary line in FIG. 8) is determined in advance. In step S150, the transmission ECU 21 uses the map based on the limited rotation range of FIG. 8 that is created in advance and stored in the ROM, and the combination of the input rotation speed Nin and the rotation speed Nout of the output shaft 27 is the above limit. It is determined whether or not it is included in the rotation range, that is, whether or not there is a possibility of causing an over-rotation state of the sun gear 36b of the Ravigneaux type planetary gear mechanism 35.

  When it is determined in step S150 that the combination of the input rotational speed Nin and the rotational speed Nout of the output shaft 27 is not included in the limited rotational range, the speed change ECU 21 forms the fourth speed that is the target speed stage Gtag. Therefore, the target shift speed formation control in step S200 described above is executed. In this case, the clutch C2, which is the first element, is completely engaged within a very short time after the shift position SP is switched from the N position to the forward travel position, and the clutch C1, which is the second element. Is gradually engaged after engagement of the clutch C2, which is the first element. Further, while the clutches C2 and C1 are engaged, a torque limit value Tlim (= T1) is transmitted to the engine ECU 14 in order to mainly suppress the heat generation of the clutch C1, which is the second element. When the input rotational speed Nin matches the synchronous rotational speed obtained by multiplying the rotational speed Nout of the output shaft 27 by the gear ratio of the target gear stage Gtag, transmission of the torque limit value Tlim to the engine ECU 14 is stopped, thereby The process of S200, that is, this routine ends.

  On the other hand, when it is determined in step S150 that the combination of the input rotation speed Nin and the rotation speed Nout of the output shaft 27 is included in the limited rotation range, the transmission ECU 21 turns on a timer (not shown). (Step S160), as shown in FIG. 9, the torque limit value Tlim is set to a positive value T0 smaller than the above-described value T1, and the set torque limit value Tlim is transmitted to the engine ECU 14 (step S170, FIG. 9). 9 at time t10). The value T0 set as the torque command value Tlim in step S170 can sufficiently reduce the rotational speed Ne of the engine 12 in a very short time even if the accelerator pedal 91 is depressed by the driver. As described above, it is determined in advance through experiments and analyses. In step S170, a target rotational speed for reducing the rotational speed of the engine 12 may be transmitted to the engine ECU 14 instead of the torque limit value Tlim. Then, after transmitting the torque limit value Tlim to the engine ECU 14, the speed change ECU 21 determines whether or not the combination of the input rotational speed Nin and the rotational speed Nout of the output shaft 27 is included in a predetermined non-release rotational range. (Step S180).

  As shown in FIG. 8, in the embodiment, it is considered that there is no possibility of causing an over-rotation state of the sun gear 36b of the Ravigneaux type planetary gear mechanism 35 due to the boundary line that defines the limited rotation range and the hysteresis based on the experiment and analysis. A torque limit release line indicating a combination of the input rotation speed Nin and the rotation speed Nout of the output shaft 27 is determined in advance. It is said that. In step S180, the speed change ECU 21 uses a map based on the non-released rotation range of FIG. 8 that is created in advance and stored in the ROM, and the combination of the input rotation speed Nin and the rotation speed Nout of the output shaft 27 is not determined. It is determined whether or not it is included in the release rotation range, that is, whether or not there is still a possibility that the sun gear 36b of the Ravigneaux type planetary gear mechanism 35 may be over-rotated.

  If the shift ECU 21 determines in step S180 that the combination of the input rotation speed Nin and the rotation speed Nout of the output shaft 27 is included in the non-release rotation range, the determination is further made that the time t measured by the timer is predetermined. It is determined whether or not time (predetermined time) tref (for example, about 1 second) or more (step S190). If it is determined in step S190 that the timer time t is less than the determination time tref, the transmission ECU 21 executes the processes of steps S170 and S180 again. That is, transmission of the torque limit value Tlim having a value T0 smaller than the value T1 to the engine ECU 14 is continued until a negative determination is made in step S180 or S190, during which the fourth speed (determination) that is the target gear stage Gtag. The target gear stage Gd) is not formed.

  As a result, as shown in FIG. 9, even when the driver depresses the accelerator pedal 91 when switching from the N position during traveling of the automobile 10 to the forward traveling position, the rotational speed Ne of the engine 12 and the input rotation The speed Nin can be reduced. When it is determined in step S180 that the combination of the input rotational speed Nin and the rotational speed Nout of the output shaft 27 is not included in the non-release rotational range (time t11 in FIG. 9), the transmission ECU 21 turns off the timer. After that (step S205), the determination target shift speed formation control in step S210 is started. That is, if it is determined that the target shift speed Gtag is the determination target shift speed Gd (fourth speed) and there is a possibility that the sun gear 36b of the Ravigneaux type planetary gear mechanism 35 may be over-rotated in step S150, basically In addition, the engagement of the clutches C2 and C1 corresponding to the determination target shift stage Gd, which is the target shift stage Gtag, is delayed until there is no possibility of causing an excessive rotation state of the sun gear 36b.

  The determination target shift speed formation control in step S210 is basically performed in the same manner as the target shift speed formation control in step S200 so that the clutch C2, which is the first element, is completely engaged within a very short time. The hydraulic pressure command value Psl2 * to the second linear solenoid valve SL2 corresponding to the clutch C2 is set, and the second element clutch C1 corresponds to the clutch C1 so that it gradually engages after the clutch C2 is engaged. The hydraulic pressure command value Psl1 * to the first linear solenoid valve SL1 is set. However, when the determination target shift speed formation control of step S210 is executed, as shown in FIG. 9, for example, a predetermined time has elapsed from the start of setting of the hydraulic pressure command value Psl2 *, and the second linear solenoid valve SL2 Until it is determined that the hydraulic pressure actually supplied to the clutch C2 coincides with the hydraulic pressure command value Psl2 * (until time t12 in FIG. 9), the above-described value T0 is set as the torque limit value Tlim and transmitted to the engine ECU 14. The

  This makes it possible to more favorably suppress the heat generation of the clutch C2, which is the first element, when the determination target shift stage Gd, that is, the fourth speed is formed. When it is determined that the hydraulic pressure actually supplied from the second linear solenoid valve SL2 to the clutch C2 matches the hydraulic pressure command value Psl2 *, the second element corresponds to the clutch C1, which is the second element, in the same manner as in step S200. The setting of the hydraulic pressure command value Psl1 * to the first linear solenoid valve SL1 is started, and the above-described value T1 is set as the torque limit value Tlim so as to mainly suppress the heat generation of the clutch C1, which is the second element. It is transmitted to the engine ECU 14. When the input rotational speed Nin matches the synchronous rotational speed obtained by multiplying the rotational speed Nout of the output shaft 27 by the gear ratio of the target gear stage Gtag, transmission of the torque limit value Tlim to the engine ECU 14 is stopped, thereby The process of S210, that is, this routine ends.

  If it is determined in step S190 that the timer time t has become equal to or greater than the determination time tref without making a negative determination in step S180, the transmission ECU 21 turns off the timer (step S215) and then step S220. The second target shift speed formation control is started. That is, automatic shifting is performed when it is determined that there is a possibility that the sun gear 36b of the Ravigneaux type planetary gear mechanism 35 may be over-rotated, and when the determination time tref has passed, there is no possibility that the sun gear 36b will be over-rotated. If the aircraft 25 is maintained in the neutral state, the driver of the automobile 10 may feel uncomfortable. Therefore, in this embodiment, in such a case, the fifth target speed on the closest high speed side of the fourth speed, which is the determination target shift speed Gd, is set as the second target shift speed, which is the second target shift speed. Second target shift speed formation control for forming the fifth speed is executed.

  The second target shift speed forming control in step S220 is the same as the target shift speed forming control in step S200, and the clutch C3 as the first element is completely engaged within a very short time. The hydraulic pressure command value Psl3 * for the third linear solenoid valve SL3 corresponding to C3 is set, and the second element clutch C2 is gradually engaged after the clutch C3 is engaged, 2 The hydraulic pressure command value Psl2 * for the linear solenoid valve SL2 is set. Further, while the clutches C3 and C2 are engaged, a torque limit value Tlim (= T1) is transmitted to the engine ECU 14 so as to mainly suppress the heat generation of the clutch C2, which is the second element. When the input rotational speed Nin matches the synchronous rotational speed obtained by multiplying the rotational speed Nout of the output shaft 27 by the gear ratio of the target gear stage Gtag, transmission of the torque limit value Tlim to the engine ECU 14 is stopped, thereby The process of S220, that is, this routine ends.

  As described above, there is still no possibility that the overgrowth state of the sun gear 36b is caused after the determination time tref has elapsed since it is determined that the overgrowth state of the sun gear 36b of the Ravigneaux planetary gear mechanism 35 may be caused. In this case, the formation of the fourth speed that is the determination target gear stage Gd is canceled and the fifth speed that is the second target gear stage is formed, thereby causing the sun gear 36b to over-rotate with the engagement of the clutch C2. While the shift position SP is switched from the N position to the forward travel position, it is possible to suppress a decrease in shift response. In the embodiment, the clutch C2 (first element) that is first engaged when the fourth speed that is the determination target gear stage Gd is formed also corresponds to the fifth speed that is the second target gear stage. However, as described above, when the fifth speed that is the second target shift speed is established, the hydraulic control device 50 (third linear solenoid valve) is set so that the clutch C3 other than the clutch C2 is engaged first. SL3) is controlled. This prevents the sun gear 36b of the Ravigneaux type planetary gear mechanism 35 from rotating at a rotational speed exceeding the permissible rotational speed in association with the engagement of the clutch C2 when the fifth speed that is the second target gear stage is formed. Is possible. Depending on the traveling state of the automobile 10, the engagement control for forming the original target gear stage Gtag (fourth speed) may be executed after the second target gear stage (fifth speed) is formed.

  As described above, the shift ECU 21 serving as the control device for the automatic transmission 25 is in the running state of the automobile 10 with the N position selected and the clutches C1 to C3 and the brakes B1 and B2 all released. It is determined that the shift position SP has been switched from the N position to the forward travel position (step S110), and the target shift stage Gtag after the switch to the forward travel position is the determination target shift stage Gd (fourth speed). The sun gear 36b of the Ravigneaux type planetary gear mechanism 35 that constitutes the automatic transmission 25 in accordance with the engagement of the clutch C2 (first element) that is engaged first among the two clutches corresponding to the determination target gear stage Gd. If it is determined that there is a risk of causing an over-rotation state that rotates at a rotation speed exceeding the allowable rotation speed (step S150), Delaying the engagement of the target gear position Gtag That determination target shift stage Gd clutches C2 and C1 corresponding to (step S160~S180, S205, S210). As described above, when there is a possibility of causing the above-described over-rotation state in forming the target gear stage Gtag after switching from the N position during traveling of the automobile 10 to the forward traveling position, the target gear stage Gtag, that is, the determination target gear stage Gd is set. By delaying the start of engagement of the corresponding clutches C2 and C1, that is, the clutch C2 that is initially engaged, it is possible to wait for the engine 12 and the input rotational speed Nin to decrease. As a result, the sun gear 36b of the automatic transmission 25 does not rotate at a rotational speed exceeding the permissible rotational speed as the clutch C2 is engaged, resulting from switching from the N position during traveling of the automobile 10 to the forward traveling position. It becomes possible to suppress the deterioration of the durability of the automatic transmission 25.

  Further, when it is determined that the sun gear 36b of the Ravigneaux type planetary gear mechanism 35 is likely to be over-rotated (step S150), the transmission ECU 21 is a torque limit that is a command value for reducing the rotational speed Ne of the engine 12. The value Tlim is transmitted to the engine ECU 14 (step S170). Thus, even when the driver depresses the accelerator pedal 91 when switching from the N position during traveling of the automobile 10 to the forward traveling position, the clutch C2 corresponding to the target gear stage Gtag, that is, the determination target gear stage Gd and While the engagement of C1 is delayed, the rotational speed Ne of the engine 12 and the input rotational speed Nin can be reduced. Therefore, in the automatic transmission 25, it is possible to very well suppress the sun gear 36b from rotating at a rotational speed exceeding the allowable rotational speed with the engagement of the clutch C2 corresponding to the determination target gear stage Gd.

  Further, when engaging the two clutches corresponding to the target gear stage Gtag, the transmission ECU 21 mainly suppresses heat generation of the clutches (second element) that are engaged later from among the two clutches. Thus, torque limit value Tlim (value T1 as the second command value) for reducing the output torque of engine 12 is transmitted to engine ECU 14 (steps S200, S210, S220). The torque limit value Tlim that is set while the engagement of the clutches C2 and C1 corresponding to the determination target gear stage Gd is delayed is the second command value so as to further reduce the output torque of the engine 12. Is set to a value T0 smaller than the value T1 (step S170). Thus, while the target shift stage Gtag is the determination target shift stage Gd and the engagement of the clutches C2 and C1 corresponding to the determination target shift stage Gd is delayed, the rotational speed Ne of the engine 12 and the input rotational speed When Nin is reduced more quickly, and when the clutches C2 and C1 are engaged, the output torque from the engine 12 is secured to suppress the deterioration of the running performance of the automobile 10, and particularly the heat generation of the clutch C2 is suppressed. It becomes possible to do.

  Further, when it is determined that the sun gear 36b of the Ravigneaux type planetary gear mechanism 35 may be over-rotated (step S150), the transmission ECU 21 is in a stage where there is no longer a possibility that the sun gear 36b is over-rotated (step S180). ), The hydraulic control device 50, that is, the second and first linear solenoid valves SL2 and SL1, are controlled so that the clutches C2 and C1 corresponding to the determination target shift stage Gd that is the target shift stage are engaged in a predetermined order. (Step S210). Accordingly, it is possible to more reliably suppress the rotation at the rotation speed exceeding the allowable rotation speed of the sun gear 36b of the automatic transmission 25 with the engagement of the clutch C2.

  Further, the speed change ECU 21 has determined that there is a possibility that the sun gear 36b of the Ravigneaux type planetary gear mechanism 35 may be over-rotated, and that there is no possibility that the sun gear 36b will be over-rotated after the determination time tref has elapsed. In this case (step S190), the clutches C3 and C2 corresponding to the second target shift speed (fifth speed) on the higher speed side than the determination target shift speed Gd (fourth speed) that is the target shift speed are determined in advance. The hydraulic control device 50, that is, the third and second linear solenoid valves SL3 and SL2 are controlled so as to be engaged in order (step S220). This suppresses the sun gear 36b of the automatic transmission 25 from rotating at a rotational speed exceeding the permissible rotational speed as the clutch C2 is engaged, and the shift position SP is shifted from the N position during the traveling of the automatic transmission 25. It is possible to suppress a decrease in the shift response when switched to the forward travel position. When the second target shift speed (fifth speed) that is higher than the determination target shift speed Gd (fourth speed) that was the initial target shift speed is formed, the determination target shift speed Gd Since the torque (driving force) transmitted to the output shaft 27 is smaller than that at the time of forming, the behavior of the automobile 10 can be stabilized and the drivability can be improved.

  In the above embodiment, the clutch C2 as the first element to be engaged first among the clutches C2 and C1 corresponding to the determination target shift speed Gd (fourth speed) is the second target shift speed (fifth speed). Therefore, when engaging the clutches C3 and C2 corresponding to the second target shift speed (fifth speed) in step S220, the clutch C3 is engaged first, not the clutch C2. The hydraulic control device 50 (third linear solenoid valve SL3) is controlled so as to match. Accordingly, when the second target shift speed (fifth speed) is formed, it is possible to prevent the sun gear 36b of the automatic transmission 25 from rotating at a rotational speed exceeding the allowable rotational speed with the engagement of the clutch C2. It becomes. However, the second target shift speed may be a shift speed higher than the determination target shift speed Gd, and corresponds to one of the clutches corresponding to the determination target shift speed Gd that is first engaged. It may be a shift stage that is not.

  Furthermore, in the above-described embodiment, the speed change ECU 21 determines whether or not there is a possibility of causing an excessive rotation state of the sun gear 36b based on the input rotation speed Nin and the rotation speed Nout of the output shaft 27 (steps S140 and S150). . As a result, it is possible to more appropriately determine whether or not there is a possibility of causing an excessive rotation state of the sun gear 36b. However, in step S150, the vehicle speed V may be used instead of the rotation speed Nout of the output shaft 27 to determine whether or not there is a possibility of causing an over-rotation state of the sun gear 36b.

  Needless to say, the determination target gear stage Gd varies depending on the configuration of the transmission, and is not limited to the fourth speed as in the above embodiment. Further, in the automatic transmission 25 according to the above-described embodiment, the speed stages from the second speed to the sixth speed except for the first speed are formed by engaging two clutches or the like corresponding to the respective speed stages. Needless to say, the present invention can also be applied to a transmission formed by engaging three or more clutches corresponding to each of a plurality of shift stages. Further, at least one of the clutches C1, C2 and C3 and the two brakes B1 and B2 of the automatic transmission 25 may be a meshing engagement element such as a dog clutch.

  Here, the correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problems will be described. That is, in the above-described embodiment, a plurality of shift stages are formed by selectively engaging the plurality of clutches C1 to C3 and the brakes B1 and B2 that are mounted on the automobile 10 and that are operated by the hydraulic pressure from the hydraulic control device 50. Then, the shift ECU 21 that controls the automatic transmission 25 that transmits the power applied from the engine 12 to the input shaft 26 to the output shaft 27 corresponds to the “control device”, and executes the processes of steps S100 and S110 of FIG. The shift ECU 21 corresponds to “shift position determination means”, the shift ECU 21 that executes the processes of steps S200, S210, and S220 in FIG. 6 corresponds to “engagement control means”, and the processes of steps S140 and S150 in FIG. The transmission ECU 21 to be executed corresponds to “over-rotation determination means”. However, the correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problem is the invention described in the column of means for solving the problem by the embodiment. Therefore, the elements of the invention described in the column of means for solving the problems are not limited. In other words, the examples are merely specific examples of the invention described in the column of means for solving the problem, and the interpretation of the invention described in the column of means for solving the problem is It should be done based on the description.

  As mentioned above, although the embodiment of the present invention has been described using examples, the present invention is not limited to the above-described examples, and various modifications can be made without departing from the scope of the present invention. Needless to say.

  The present invention can be used in the transmission manufacturing industry.

  DESCRIPTION OF SYMBOLS 10 Automotive, 12 Engine, 14 Engine electronic control unit (engine ECU), 16 Brake electronic control unit (brake ECU), 20 Power transmission device, 21 Transmission electronic control unit (transmission ECU), 22 Transmission case, 23 Fluid Transmission device, 23a pump impeller, 23b turbine runner, 23c lock-up clutch, 24 oil pump, 25 automatic transmission, 26 input shaft, 27 output shaft, 28 gear mechanism, 29 differential mechanism, 30 single pinion planetary gear mechanism, 31, 36a, 36b Sun gear, 32, 37 ring gear, 33 pinion gear, 34, 39 carrier, 35 Ravigneaux planetary gear mechanism, 38a short pinion gear, 38b long pinion gear, 50 hydraulic control device, 51 primer Regulator valve, 52 Manual valve, 53 Apply control valve, 91 Accel pedal, 92 Accel pedal position sensor, 93 Brake pedal, 94 Master cylinder pressure sensor, 95 Shift lever, 96 Shift position sensor, 97 Vehicle speed sensor, 98 Rotation speed sensor, 99 Oil temperature sensor, B1, B2 brake, C1, C2, C3 clutch, F1 one-way clutch, SL1 1st linear solenoid valve, SL2 2nd linear solenoid valve, SL3 3rd linear solenoid valve, SL4 4th linear solenoid valve, SLT Linear solenoid valve.

Claims (8)

A plurality of shift elements are formed by selectively engaging a plurality of engagement elements that are mounted on a vehicle and operated by hydraulic pressure from a hydraulic control device, and the power applied from the prime mover to the input member is used as an output member. In the transmission control device for transmission,
Shift position determination means for determining whether or not the shift position has been switched from the neutral position to the forward travel position during travel of the vehicle in a state in which a neutral position is selected and all of the engagement elements are released; ,
The shift position determining means determines that the shift position has been switched from the neutral position to the forward travel position, and at least two of the engagements to form a target gear position after switching to the forward travel position. Engagement control means for controlling the hydraulic control device so that the at least two engagement elements are engaged in a predetermined order when the combination element is to be engaged;
When the shift position determination means determines that the shift position has been switched from the neutral position to the forward travel position, the first engagement of the at least two engagement elements corresponding to the target shift stage is performed. Over-rotation for determining whether there is a possibility of causing an over-rotation state in which any of the rotation elements constituting the transmission rotates at a rotation speed exceeding an allowable rotation speed with the engagement of the first element to be combined Determination means,
The engagement control means delays the engagement of the at least two engagement elements corresponding to the target shift speed when it is determined by the over-rotation determination means that the over-rotation state is likely to occur. A control device for a transmission. The transmission control device according to claim 1,
When it is determined that the over-rotation state is likely to be caused by the over-rotation determination unit, the engagement control unit is configured to perform the at least 2 corresponding to the target shift speed when the over-rotation state is not likely to be caused The transmission control apparatus, wherein the hydraulic control apparatus is controlled so that the two engagement elements are engaged in the order. The transmission control device according to claim 1 or 2,
The engagement control means, when it is determined that there is a possibility that the over-rotation state is likely to be caused by the over-rotation determination means, and the target speed change is not eliminated when a predetermined time has passed. A transmission that controls the hydraulic control device such that at least two engagement elements corresponding to a second target shift speed on a higher speed side than the speed are engaged in a predetermined order. Control device. The transmission control device according to claim 3,
When the first element corresponds to the second target shift speed, the engagement control means includes the first element of at least two engagement elements corresponding to the second target shift speed. A control apparatus for a transmission, wherein the hydraulic control apparatus is controlled such that an engagement element other than the first engaging element is engaged. In the transmission control device according to any one of claims 1 to 4,
The engagement control means transmits a command value for lowering the rotational speed of the prime mover to the control apparatus of the prime mover when it is judged by the over revolution judgment means that there is a risk of causing the overspeed state. A control device for a transmission. The transmission control device according to claim 5,
The engagement control means limits the output torque of the prime mover so that heat generation of the engagement elements is suppressed when engaging the at least two engagement elements corresponding to the target shift speed. The second command value is transmitted to the control device of the prime mover, and the command value is determined so as to greatly reduce the output torque of the prime mover than the second command value. Control device. The transmission control device according to any one of claims 1 to 6,
The transmission control device according to claim 1, wherein the over-rotation determination unit determines whether or not the over-rotation state is likely to occur based on a rotation speed of the input member and a rotation speed of the output member. A plurality of shift elements are formed by selectively engaging a plurality of engagement elements that are mounted on a vehicle and operated by hydraulic pressure from a hydraulic control device, and the power applied from the prime mover to the input member is used as an output member. In a control method of a transmission for transmission,
(A) determining whether or not the shift position has been switched from the neutral position to the forward travel position during travel of the vehicle with the neutral position selected and all of the engagement elements released; ,
(B) when it is determined in step (a) that the shift position has been switched from the neutral position to the forward travel position, a target gear position of the transmission is set;
(C) When at least two of the engagement elements are to be engaged to form the target gear set in step (b), the first engagement of the at least two engagement elements Determining whether there is a possibility of causing an over-rotation state in which any of the rotating elements constituting the transmission rotates at a rotation speed exceeding an allowable rotation speed in accordance with the engagement of the first element to be performed;
(D) controlling the hydraulic control device so that at least two engaging elements corresponding to the target gear set in step (b) are engaged in a predetermined order; and step (c) Delaying the engagement of the at least two engagement elements corresponding to the target shift stage when it is determined that there is a risk of causing the overspeed state at
A transmission control method including:

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