JP2013087826A - Control device for automatic transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To rapidly form a backward stage even for shift operation from a forward position to a backward position.SOLUTION: In a transmission configured to attain a backward stage by engagement of a brake B2 with a clutch 3C, when a shift lever is at D position (S210), an oil pressure instruction PB2* is set so as to be higher as vehicle speed V is lower (S250) when the vehicle speed V is less than a predetermined vehicle speed Vref, and a linear solenoid valve SL3 is drive-controlled with the set hydraulic instruction PB2* (S260). According to this, the brake B2 can be waited at a standby pressure as high as possible in the state of D position without giving a sense of discomfort due to deceleration to a driver. Consequently, the waiting time to start the engagement of the clutch C3 can be minimized, and the backward stage can be rapidly formed.

Description

  The present invention is mounted on a vehicle equipped with a prime mover, and when the shift position is a reverse position, the first friction engagement element and the second friction engagement element are engaged with a predetermined engagement pressure, and the shift position is The present invention relates to a control device for an automatic transmission that waits a first friction engagement element at a standby pressure lower than the engagement pressure when the predetermined position includes a forward position other than the reverse position.

  Conventionally, as a control device of this type of automatic transmission, the reverse lever is achieved by engaging (engaging) a plurality of friction elements, and the shift lever is in a parking (parking) position or neutral (neutral) An element that engages one of a plurality of reverse-stage frictional engagement elements when positioned at any one of the positions has been proposed (see, for example, Patent Document 1). In this device, by engaging one of the plurality of reverse friction engagement elements in advance in the parking position or the neutral position, when the reverse (reverse) position is switched, the remaining Since it is only necessary to engage the frictional engagement element, the reverse gear can be achieved quickly.

JP 2003-106435 A

  However, in the above-described apparatus, considering the case where the shift operation is quickly performed from the drive (forward) position to the reverse position via the neutral position, sufficient time for engaging the friction engagement element at the neutral position is obtained. Therefore, it is necessary to engage all of the plurality of necessary friction engagement elements in the state switched to the reverse position. For this reason, the amount of oil necessary for engaging the plurality of friction engagement elements may be insufficient, and a delay may occur in the formation of the reverse gear.

  A control device for an automatic transmission according to the present invention is mainly intended to quickly form a reverse gear for a shift operation from a forward position to a reverse position.

  The control device for an automatic transmission according to the present invention employs the following means in order to achieve the main object described above.

The control device for the automatic transmission according to the present invention includes:
A control device for an automatic transmission that is mounted on a vehicle equipped with a prime mover and that engages a first friction engagement element and a second friction engagement element with a predetermined engagement pressure when the shift position is a reverse position. There,
When the shift position is a predetermined position including a forward position other than the reverse position, the standby pressure is set so as to be lower as the engagement pressure and higher as the vehicle speed is lower, and the standby pressure is set with the set standby pressure. The gist is to wait for one frictional engagement element.

  In this automatic transmission control device of the present invention, when the shift position is the reverse position, the first friction engagement element and the second friction engagement element are engaged with a predetermined engagement pressure. When the shift position is a predetermined position including a forward position other than the reverse position, the standby pressure is set so as to become higher as the vehicle speed is lower than the engagement pressure and the first frictional engagement is set with the set standby pressure. Wait for the combined element. As a result, it is possible to quickly form the reverse gear for the shift operation from the forward position to the reverse position. In addition, since the standby pressure is set so as to increase as the vehicle speed decreases, the reverse gear can be formed more quickly when the vehicle speed is relatively low, and drag of the friction engagement element is reduced when the vehicle speed is relatively high. It is possible to suppress the occurrence of shock due to dragging of the frictional engagement element, and it is possible to suppress heat generation due to dragging of the frictional engagement element.

  In such an automatic transmission control device of the present invention, when the vehicle speed is less than a predetermined vehicle speed, the standby pressure is set so as to increase as the vehicle speed decreases, and when the vehicle speed is equal to or higher than the predetermined vehicle speed, a value of 0 is set as the standby pressure. It can also be set. In this way, it is possible to completely prevent the frictional engagement element from being dragged when the vehicle speed is higher than the predetermined vehicle speed, to suppress the occurrence of shock due to the frictional engagement element dragging, and to suppress the heat generation due to the frictional engagement element dragging. Can do.

  In the control device for an automatic transmission according to the present invention, the standby pressure may be set such that a pressure at which the first friction engagement element has a torque capacity is set as a lower limit pressure. In this way, even if there is a slight variation in the hydraulic pressure or stroke end pressure applied to the first friction engagement element, the first friction engagement element can be made to stand by at least at a standby pressure near the stroke end pressure. Therefore, the reverse gear can be quickly formed in response to the shift operation from the forward position to the reverse position.

  As an automatic transmission, a pump that operates by power from the prime mover and pumps hydraulic oil to a pump oil passage, and a pressure regulator that inputs and regulates the hydraulic pressure of the pump oil passage and outputs the pressure to a pressure adjustment oil passage. When the shift operation is shifted to a position other than the reverse drive position in conjunction with the shift operation, the communication between the pump oil passage and the reverse drive oil passage is cut off and the shift operation is performed to the reverse drive position. Is a first switch that communicates the pump oil passage with the reverse oil passage, and a first switch that communicates with the reverse oil passage, the pressure adjusting oil passage, and the oil chamber of the first friction engagement element. When the shift oil is connected to a first engagement oil passage and a second engagement oil passage communicating with the oil chamber of the second friction engagement element and is shifted to a position other than the reverse drive position, the reverse drive is performed. The communication between the oil passage and the first engagement oil passage is blocked. In addition, when the pressure adjusting oil passage and the first engagement oil passage are communicated and shifted to the reverse position, the reverse oil passage and the first engagement oil passage are communicated. In addition, in the control device for an automatic transmission according to any one of the above-described aspects, the shift position includes: a second switch that communicates the pressure adjusting oil passage and the second engagement oil passage. When the position is other than the reverse position, the pressure regulator is driven and controlled so that the first friction engagement element stands by at the standby pressure, and the shift operation is performed from the position other than the reverse position to the reverse position. The pressure regulator may be driven and controlled so that the engagement of the second friction engagement element is started after waiting for the first friction engagement element to be engaged.

1 is a configuration diagram showing an outline of a configuration of an automobile 10 equipped with an automatic transmission control device as an embodiment of the present invention. 2 is a configuration diagram showing an outline of the configuration of an automatic transmission 20. FIG. 4 is an explanatory diagram showing an operation table of the speed change mechanism 26. FIG. FIG. 6 is a velocity diagram showing the relationship between the rotational speeds of the rotary elements of the speed change mechanism 26; FIG. 2 is a configuration diagram showing an outline of a configuration of a hydraulic circuit 40. 3 is a flowchart showing an example of a reverse shift control routine executed by an ATECU 28; 7 is a flowchart showing an example of a B2 low pressure standby control routine executed by an ATECU 28. It is explanatory drawing which shows an example of the map for oil pressure command setting. It is explanatory drawing which shows an example of the map for oil pressure command setting. It is explanatory drawing which shows the mode of the time change of the vehicle speed V, B2 hydraulic pressure command PB2 *, and C3 hydraulic pressure command at the time of the shift lever 81 being operated from D position to R position during forward drive in D position.

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

  FIG. 1 is a configuration diagram showing an outline of the configuration of an automobile 10 equipped with a control device for an automatic transmission as an embodiment of the present invention, and FIG. 2 is a configuration diagram showing an outline of the configuration of an automatic transmission 20. 3 is an explanatory view showing an operation table of the speed change mechanism 26, and FIG. 4 is a speed diagram showing the relationship between the rotational speeds of the rotating elements of the speed change mechanism 26.

  As shown in FIG. 1, an automobile 10 according to an embodiment includes an engine 12 as an internal combustion engine that outputs power by explosion combustion of a hydrocarbon-based fuel such as gasoline or light oil, and an electronic control for the engine that controls the operation of the engine 12. A unit (hereinafter referred to as an engine ECU) 16 and a crankshaft 14 (see FIG. 2) of the engine 12 are connected to the axles 18a and 18b of the left and right wheels 19a and 19b to shift the power from the engine 12. An automatic transmission 20 that transmits to the axles 18a and 18b, an electronic control unit for transmission (hereinafter referred to as ATECU) 29 that controls the automatic transmission 20, and a main electronic control unit (hereinafter referred to as main control unit) that controls the entire vehicle. 70). The main ECU 70 determines the shift position SP from the shift position sensor 82 that detects the operation position of the shift lever 81, the accelerator opening Acc from the accelerator pedal position sensor 84 that detects the depression amount of the accelerator pedal 83, and the brake pedal 85. A brake switch signal BSW from the brake switch 86 that detects the depression, a vehicle speed V from the vehicle speed sensor 88, and the like are input. In the embodiment, the shift position of the shift lever 81 includes a parking position (P position) used during parking, a reverse position (R position) for reverse travel, a neutral position (N position), and a normal drive position for forward travel. (D position), a low position (L position) for applying the engine brake when the accelerator is off, and the like are prepared. The main ECU 70 is connected to the engine ECU 16 and the ATECU 29 via a communication port, and exchanges various control signals and data with the engine ECU 16 and the ATECU 29.

  As shown in FIG. 2, the automatic transmission 20 is configured as a transaxle device that transmits power from the engine 12 to the axles 18 a and 18 b, and an input-side pump impeller connected to the crankshaft 14 of the engine 12. A torque converter 24 with a lock-up clutch comprising a turbine runner 24b on the output side and an input shaft 21 connected to the turbine runner 24b of the torque converter 24 and a gear mechanism 27 and a differential gear 28 on the axles 18a and 18b. And a stepped transmission mechanism 26 that shifts the power input to the input shaft 21 and outputs it to the output shaft 22, and a hydraulic circuit 40 that drives and controls the transmission mechanism 26 (see FIG. 1).

  The speed change mechanism 26 is configured as a stepped transmission with six speeds, and includes a single pinion type planetary gear mechanism 30, a Ravigneaux type planetary gear mechanism 35, three clutches C1, C2, C3, and two brakes B1, B2 and a one-way clutch F1 are provided. The single pinion type planetary gear mechanism 30 includes a sun gear 31 as an external gear, a ring gear 32 as an internal gear arranged concentrically with the sun gear 31, and a plurality of gears meshed with the sun gear 31 and meshed with the ring gear 32. The pinion gear 33 and a carrier 34 that holds the plurality of pinion gears 33 so as to rotate and revolve freely. The sun gear 31 is fixed to the case of the automatic transmission 20, and the ring gear 32 is connected to the input shaft 21. The Ravigneaux planetary gear mechanism 35 includes two sun gears 36a and 36b as external gears, a ring gear 37 as an internal gear, a plurality of short pinion gears 38a meshing with the sun gear 36a, a sun gear 36b, and a plurality of short pinion gears 38a. The sun gear 36a includes a plurality of long pinion gears 38b that mesh with the ring gear 37, and a carrier 39 that connects the plurality of short pinion gears 38a and the plurality of long pinion gears 38b to hold the clutch C1 in a freely rotating and revolving manner. The sun gear 36b is connected to the carrier 34 via the clutch C3 and connected to the case of the automatic transmission 20 via the brake B1, and the ring gear 37 is connected to the carrier 34 of the single pinion planetary gear mechanism 30 via the brake C1. Connected to output shaft 22 Is, the carrier 39 is connected to the input shaft 21 via the clutch C2. Further, the carrier 39 is connected to the case of the automatic transmission 20 via the one-way clutch F1, and its rotation is regulated in one direction, and automatically via a brake B2 provided in parallel to the one-way clutch F1. It is connected to the case of the transmission 20.

  As shown in the operation table of FIG. 3, the speed change mechanism 26 changes forward 1st to 6th, reverse, and neutral by turning on and off (engaging and releasing) the clutches C1 to C3 and turning on and off the brakes B1 and B2. It can be switched. The reverse speed can be formed by turning on the clutch C3 and the brake B2 and turning off the clutches C1 and C2 and the brake B1. Further, the first forward speed can be formed by turning on the clutch C1 and turning off the clutches C2 and C3 and the brakes B1 and B2. In the first forward speed, the brake B2 is turned on during engine braking. The second forward speed can be formed by turning on the clutch C1 and the brake B1 and turning off the clutches C2 and C3 and the brake B2. The third forward speed can be formed by turning on the clutches C1 and C3 and turning off the clutch C2 and the brakes B1 and B2. The fourth forward speed can be formed by turning on the clutches C1 and C2 and turning off the clutch C3 and the brakes B1 and B2. The fifth forward speed can be formed by turning on the clutches C2 and C3 and turning off the clutch C1 and the brakes B1 and B2. The sixth forward speed can be formed by turning on the clutch C2 and the brake B1 and turning off the clutches C1 and C3 and the brake B2. The neutral can be formed by turning on the brake B2 and turning off the clutches C1 to C3 and the brake B1, or by turning off all the clutches C1 to C3 and the brakes B1 and B2. it can. In the embodiment, the neutral is formed by the former engagement pattern.

  Further, as shown in the speed diagram of FIG. 4, in the reverse speed, the speed change mechanism 26 is decelerated by the reaction force applied to the ring gear 32 from the input shaft 21 by the sun gear 31 fixed to the case. The power that is output to the carrier 34 and input to the sun gear 36b from the carrier 34 via the clutch C3 is counter-rotated by receiving a reaction force on the carrier 39 to which the brake B2 is connected, so that the ring gear 37, that is, the output shaft 22 is rotated. Is output. In the first forward speed, the power input from the input shaft 21 to the ring gear 32 is decelerated by receiving a reaction force at the sun gear 31 fixed to the case, and is output to the carrier 34 and is also output from the carrier 34 via the clutch C1. The power input to the sun gear 36a is decelerated by receiving a reaction force in the carrier 39 to which the one-way clutch F1 is connected, and is output to the ring gear 37, that is, the output shaft 22. In the second forward speed, the power input from the input shaft 21 to the ring gear 32 is decelerated by receiving a reaction force from the sun gear 31 fixed to the case, and is output to the carrier 34 and is also output from the carrier 34 via the clutch C1. The power input to the sun gear 36a is decelerated by receiving a reaction force at the sun gear 36b to which the brake B1 is connected, and is output to the ring gear 37, that is, the output shaft 22. In the third forward speed, the power input from the input shaft 21 to the ring gear 32 is decelerated by receiving a reaction force from the sun gear 31 fixed to the case, and is output to the carrier 34. The carrier 34 also receives the clutch C1 and the clutch C3. The power that is output to the sun gear 36a and the sun gear 36b through the two gears is output to the ring gear 37, that is, the output shaft 22 at a constant speed by the integral rotation of the sun gears 36a and 36b, the ring gear 37, and the carrier 39. In the fourth forward speed, the power input from the input shaft 21 to the ring gear 32 is decelerated by receiving a reaction force from the sun gear 31 fixed to the case, and is output to the carrier 34 and also from the carrier 34 via the clutch C1. Power is output to the ring gear 37, that is, the output shaft 22 by the power output to the sun gear 36 a and the power output from the ring gear 32 to the carrier 39 at a constant speed via the clutch C 2. In the fifth forward speed, the power input from the input shaft 21 to the ring gear 32 is decelerated by receiving a reaction force at the sun gear 31 fixed to the case, and is output to the carrier 34 and is also output from the carrier 34 via the clutch C3. Power is output to the ring gear 37, that is, the output shaft 22, by the power output to the sun gear 36b and the power output from the ring gear 32 to the carrier 39 at a constant speed via the clutch C2. At the sixth forward speed, the power output from the input shaft 21 to the ring gear 32 is output to the carrier 39 via the clutch C2, and the power from the carrier 39 is responsible for the reaction force at the sun gear 36b to which the brake B1 is connected. , And output to the ring gear 32, that is, the output shaft 22.

  The hydraulic circuit 40 turns on and off the clutches C1 to C3 and on and off the brakes B1 and B2 in the transmission mechanism 26. FIG. 5 shows a schematic configuration of the hydraulic circuit 40. As shown in FIG. 5, the hydraulic circuit 40 includes a mechanical oil pump 44 that is operated by power from the engine 12, sucks hydraulic oil through the strainer 42, and pumps the hydraulic oil to the line pressure oil passage 51, and the line pressure oil passage. By regulating the hydraulic oil pumped to 51 to generate a line pressure PL, and regulating the modulator pressure PMOD generated from the line pressure PL via a modulator valve (not shown) and outputting it as a signal pressure A linear solenoid valve SLT for driving the regulator valve 46, an input port 48a connected to the line pressure oil passage 51, a D position output port 48b connected to the drive pressure oil passage 52, and a reverse pressure oil passage 53. R position output port 48c etc. are formed and shift lever 81 is operated to D position The input port 48a communicates with the D-position output port 48b while the input port 48a is disconnected from the R-position output port 48c. When the communication with the output port 48b is cut off and the input port 48a and the R-position output port 48c are connected to each other and the N-position is operated, the input port 48a, the D-position output port 48b and the R-position output port 48c The manual valve 48 that cuts off the communication, the linear solenoid valve SL1 that inputs and regulates the drive pressure, which is the output pressure from the D-position output port 48b, and outputs it to the oil chamber of the clutch C1, and the drive pressure Pressure and output to the oil chamber of the clutch C2. A solenoid valve SL2, a linear solenoid valve SL3 that inputs and regulates the line pressure PL and outputs it to the SL3 pressure oil passage 54, and a linear solenoid valve SL4 that inputs and regulates the drive pressure and outputs it to the oil chamber of the brake B1. The supply of the SL3 pressure, which is the output pressure of the linear solenoid valve SL3, to the clutch C3 and the supply to the brake B2 are selectively performed, and the reverse pressure, which is the output pressure from the R-position output port 48c, is supplied to the brake B2. A switching valve 60 that selectively supplies and shuts off, and an on / off solenoid valve S1 that outputs a signal pressure for driving the switching valve 60 are provided. The on / off solenoid valve S1 is controlled to stop outputting signal pressure when the shift lever 81 is in the R position and to output signal pressure when the shift lever 81 is in a position other than the R position.

  The switching valve 60 is configured as a spool valve that includes a sleeve 62 in which various ports are formed, a spool 64 that communicates and blocks the corresponding ports, and a spring 66 that biases the spool 64. The sleeve 62 is connected to a signal pressure input port 62a for inputting a signal pressure for pressing the spool 64 in a direction opposite to the biasing force of the spring 66 from the on / off solenoid valve S1 and a reverse pressure oil passage 53 as various ports. An input port 62b, an input port 62c connected to the SL3 pressure oil passage 54, an output port 62d connected to the C3 oil passage 55 communicating with the oil chamber of the clutch C3, and B2 communicating with the oil chamber of the brake B2. An output port 62e connected to the oil passage 56 is formed. In this switching valve 60, when the signal pressure is inputted from the on / off solenoid valve S1 to the signal pressure input port 62a, the spool 64 is pressed by the pressing force overcoming the urging force of the spring 66, and the spring 66 is contracted in the contracting direction. 64 moves, and the communication between the input port 62c and the output port 62d is cut off, the communication between the input port 62c and the output port 62e is made, and the communication between the input port 62b and the output port 62e is cut off. Thus, the SL3 pressure from the linear solenoid valve SL3 is supplied to the oil chamber of the brake B2 via the SL3 pressure oil passage 54, the switching valve 60 (input port 62b and output port 62e), and the B2 oil passage 56. it can. On the other hand, when no signal pressure is input to the signal pressure input port 62a, the spool 64 moves in the direction in which the spring 66 extends, and the input port 62c and the output port 62d are communicated with each other and the input port 62c and the output port 62e are connected. And the communication between the input port 62b and the output port 62e. Thus, the SL3 pressure from the linear solenoid valve SL3 is supplied to the oil chamber of the clutch C3 via the SL3 pressure oil passage 54, the switching valve 60 (input port 62c and output port 62d), and the C3 oil passage 55. In addition, the reverse pressure from the manual valve 48 can be supplied to the oil chamber of the brake B2 via the reverse pressure oil passage 53, the switching valve 60 (input port 62b and output port 62e), and the B2 oil passage 56. .

  The operation of the automobile 10 according to the embodiment configured as described above, particularly the operation when the shift operation is performed from the position other than the R position (for example, P position, N position, D position, etc.) to the R position will be described. FIG. 6 is a flowchart illustrating an example of a reverse shift control routine executed by the ATECU 29. This routine is executed when the shift position SP from the shift position sensor 82 is switched from a position other than the R position to the R position.

  When the reverse shift control routine is executed, the CPU of the ATECU 29 first waits until the engagement of the brake B2 is completed (step S100). Now, considering that the shift lever 81 is switched from another position to the R position, the manual valve 48 communicates with the input port 48a and the R position output port 48c, and the switching valve 60 outputs with the input port 62b. It communicates with the port 62e. Therefore, the hydraulic oil in the line pressure oil passage 51 is a manual valve 48 (input port 48a and R-position output port 48c), reverse pressure oil passage 53, switching valve 60 (input port 62b and output port 62e), oil for B2. The oil is introduced into the oil chamber of the brake B2 through the path 56 in order, and the brake B2 is automatically engaged. The determination in step S100 is performed, for example, by detecting the hydraulic pressure acting on the oil chamber of the brake B2 using a hydraulic sensor or the like, or based on the elapsed time since switching from the shift lever 81 to the R position. be able to. When it is determined that the engagement of the brake B2 has been completed, a fast fill is performed to set a relatively high hydraulic pressure command so that the hydraulic oil is quickly charged into the clutch C3 and to drive and control the linear solenoid valve SL3 (step). S110). As described above, when the shift lever 81 is in the R position, the switching valve 60 communicates with the input port 62c and the output port 62d. Therefore, the linear solenoid valve SL3 is driven to control the oil chamber of the clutch C3. Oil can be supplied. When the fast fill is executed, the linear solenoid valve SL3 is driven and controlled so as to stand by while maintaining a relatively low hydraulic pressure command (low pressure standby) (step S120). Then, after detecting the rotation change of the input shaft (that is, after determining the start of engagement of the clutch C3), the sweep for driving and controlling the linear solenoid valve SL3 so that the hydraulic pressure applied to the oil chamber of the clutch C3 gradually increases. Apply control is executed (step S130), and the clutch C3 is engaged, that is, the clutch C3 is fully engaged and has sufficient torque capacity (step S140), and is supplied to the oil chamber of the clutch C3. The hydraulic pressure is maximized (step S150), and this routine is terminated.

  Next, the low pressure standby operation of the brake B2 when the shift lever 81 is in a position other than the R position will be described. FIG. 7 is a flowchart showing an example of a B2 low pressure standby control routine executed by the ATECU 29. This routine is repeatedly executed every predetermined time (for example, every several msec).

  When the B2 low pressure standby control routine is executed, the CPU of the ATECU 29 first executes a process of inputting data such as the vehicle speed V, the shift position SP, the engine rotational speed Ne, and the oil temperature Toil (step S200). Here, the vehicle speed V detected by the vehicle speed sensor 88 is input from the main ECU 70 by communication. The shift position SP is detected by the shift position sensor 82 and input from the main ECU 70 by communication. The engine rotation speed Ne is detected and calculated by a crank position sensor (not shown) attached to the crankshaft 14 and input from the engine ECU 16 by communication. The oil temperature Toil is input as detected by a temperature sensor (not shown) attached to the oil passage of the hydraulic circuit 40.

  When the data is input in this way, it is determined whether or not the input shift position SP is a position other than the R position, that is, the P position, the N position or the D position in the embodiment (step S210). In this embodiment, in the case of the D position, this determination is made positively at either the first forward speed or the second forward speed, and negative when the forward speed is 3 to 6. Judgment was made. Even if the shift position SP is the R position or the D position, this routine is terminated as it is when the forward third speed to the sixth speed are selected. On the other hand, when the shift position SP is either the P position, the N position or the D position, the first forward speed or the second forward speed, the input oil temperature Toil is the lower limit of the appropriate temperature range in which a stable piston stroke is possible. It is determined whether the engine 22 is at or above the predetermined temperature Tref (step S220), whether the input vehicle speed V is less than the predetermined vehicle speed Vref that is the upper limit of the vehicle speed range where the engagement shock is small (step S230), It is respectively determined whether or not the rotation speed is equal to or higher than a predetermined rotation speed Nref that is the lower limit of the stable rotation speed range (step S240). If any of the above-described determinations is a negative determination, this routine is terminated as it is. On the other hand, if any of the above-described determinations is affirmative, a hydraulic pressure command PB2 * is set based on the vehicle speed V (step S250), and the linear solenoid valve SL3 is driven based on the set hydraulic pressure command PB2 *. Control is performed (step S260), and this routine is terminated. Here, in the embodiment, the hydraulic pressure command PB2 * is obtained in advance by storing the relationship between the vehicle speed V and the hydraulic pressure command PB2 * for each shift position SP as a map in the ROM, and the shift position SP and the vehicle speed V are given. If so, the corresponding hydraulic pressure command PB2 * is derived from the hydraulic pressure command setting map and set. An example of the hydraulic pressure command setting map when the shift position SP is the D position is shown in FIGS. 8 is a map at the first forward speed, and FIG. 9 is a map at the second forward speed. As shown in the figure, the hydraulic pressure command PB2 * increases linearly as the vehicle speed V is lower when the vehicle speed V is lower than the predetermined vehicle speed Vref, and the lower limit pressure when the vehicle speed V is the predetermined vehicle speed Vref is the torque capacity of the brake B2. Is set to be a predetermined pressure P1 (pressure higher than the piston stroke end pressure). Consider a case where the shift lever 81 is traveling at the first forward speed at the D position. In this case, when the brake B2 is engaged, when the drive torque is being output from the engine 12, the brake B2 is merely a reaction force element for transmitting the drive torque to the output shaft 22, as shown in FIG. However, if the brake B2 is engaged when no driving torque is being output from the engine 12, the rotational resistance of the engine 12 is transmitted to the output shaft 22 via the brake B2, and depending on the degree, the driver decelerates. Give a sense of incongruity (deceleration). Since such a phenomenon appears more strongly as the vehicle speed V is higher, by increasing the vehicle speed V, the brake B2 can stand by at the highest possible standby pressure without giving the driver a feeling of deceleration. Therefore, even when the shift operation is quickly performed from the state (D position) to the R position, the brake B2 can be quickly and completely engaged. Therefore, the brake B2 in step S100 of the reverse shift control routine of FIG. The engagement waiting time can be reduced, and the reverse gear can be formed quickly. When the shift position SP is the D position and the second forward speed is formed, the rotation speed of the carrier 39 tends to be higher than when the first forward speed is formed (see FIG. 4). ) When the brake B2 is dragged, a feeling of deceleration appears strongly. Therefore, in the embodiment, as shown in FIG. 9, the predetermined vehicle speed Vref that prohibits the standby engagement of the brake B2 is compared with the first forward speed. It was set low. Further, when the shift position SP is the N position or the P position, the crankshaft 14 of the engine 22 is disconnected, so that the standby pressure of the brake B2 may be set higher than the D position.

  FIG. 10 is an explanatory diagram showing changes over time in the vehicle speed V, the B2 hydraulic pressure command, and the C3 hydraulic pressure command when the shift lever 81 is operated from the D position to the R position during forward traveling at the D position. When the vehicle speed V becomes less than the predetermined vehicle speed Vref at time t1, a hydraulic pressure command PB2 * exceeding the stroke end pressure is set, and the linear solenoid valve SL3 is driven and controlled based on the hydraulic pressure command PB2 * to supply hydraulic pressure to the oil chamber of the brake B2. To start. Since the hydraulic pressure command PB2 * is set higher as the vehicle speed V is lower, the brake B2 can be kept on standby at the highest possible standby pressure without giving the driver a feeling of deceleration. When the shift lever 81 is switched from the D position to the R position at time t2, reverse pressure is applied to the oil chamber of the brake B2 from the manual valve 48 instead of the linear solenoid valve SL3, and the brake B2 is completely engaged at time t3. As soon as they are combined, the engagement of the clutch C3 is started, and the reverse gear is quickly formed.

  According to the automatic transmission control apparatus of the embodiment described above, when the shift lever 81 is in the D position, the hydraulic pressure command PB2 * is set so that the lower the vehicle speed V is, the higher the vehicle speed V is when the vehicle speed V is less than the predetermined vehicle speed Vref. Since the linear solenoid valve SL3 is driven and controlled with the set hydraulic pressure command PB2 *, the brake B2 can be kept at a standby pressure as high as possible in the D position without giving the driver a sense of incongruity due to deceleration. it can. As a result, the waiting time until the engagement of the clutch C3 is started can be reduced, and the reverse gear can be quickly formed. In addition, when the vehicle speed V is equal to or higher than the predetermined vehicle speed Vref, the hydraulic pressure command PB2 * is set to a value of 0, that is, no hydraulic pressure is applied to the brake B2, so that it is possible to more reliably prevent the driver from feeling decelerated. it can. Further, since the pressure P1 exceeding the stroke end pressure is set as the lower limit as the standby pressure of the brake B2, even if the hydraulic pressure supplied to the oil chamber of the brake B2 or the stroke end pressure is slightly varied, the brake B2 is at least the stroke end pressure. It is possible to wait at a nearby standby pressure, and it is possible to quickly form a reverse gear in response to a shift operation from the D position to the R position.

  In the embodiment, as shown in FIG. 8, when the vehicle speed V is less than the predetermined vehicle speed Vref, the relationship (map) between the vehicle speed V and the hydraulic pressure command PB2 * so that the hydraulic pressure command PB2 * increases linearly as the vehicle speed V decreases. However, the present invention is not limited to this, and the relationship (map) between the vehicle speed V and the hydraulic pressure command PB2 * may be set so that the hydraulic pressure command PB2 * increases nonlinearly as the vehicle speed V decreases. Alternatively, the relationship between the vehicle speed V and the hydraulic pressure command PB2 * may be set so that the hydraulic pressure command PB2 * increases stepwise as the vehicle speed V decreases. In the latter case, the number of stages of the hydraulic pressure command PB2 * may be any number.

  In the embodiment, when the vehicle speed V is equal to or higher than the predetermined vehicle speed Vref, the hydraulic pressure command PB2 * of the brake B2 is set to the value 0. However, it is not always necessary to set the value 0, and the pressure higher than the value 0 and lower than the predetermined pressure P1. It is good also as what is set to.

  In the embodiment, even when the shift position SP is a position other than the R position and the vehicle speed V is lower than the predetermined vehicle speed Vref, the low pressure standby control of the brake B2 is not performed when the oil temperature Toil is lower than the predetermined temperature Tref. The low pressure standby control of the brake B2 may be performed regardless of the oil temperature Toil.

  In the embodiment, the description has been made by applying to the automatic transmission 20 of the 6-speed shift from the first forward speed to the sixth speed. However, the present invention is not limited to this, and the 4-speed, 5-speed, 8-speed, etc. The present invention may be applied to any number of automatic transmissions.

  In the embodiment, when the shift lever 82 is in the D position and the first forward speed or the second forward speed is formed, the brake B2 necessary for forming the reverse speed is standbyly engaged. The brake B2 may be standby-engaged only when is formed, and hydraulic pressure may not be applied to the brake B2 when the second forward speed is formed. Further, depending on the structure of the speed change mechanism, the brake B2 may be engaged in standby even when a speed greater than the third forward speed is formed.

  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. In the embodiment, the engine 22 corresponds to a “motor”, the brake B2 corresponds to a “first friction engagement element”, and the clutch C3 corresponds to a “second friction engagement element”. The mechanical oil pump 42 corresponds to a “pump”, the linear solenoid valve SL3 corresponds to a “pressure regulator”, the manual valve 48 corresponds to a “first switch”, and the switch valve 60 corresponds to a “second switch”. Corresponds to the “switching device”. Here, the “prime motor” is not limited to an internal combustion engine that outputs power using a hydrocarbon-based fuel, and may be another type of internal combustion engine such as a hydrogen engine, or an electric motor other than the internal combustion engine. It doesn't matter. The “pressure regulator” is not limited to the one configured as a linear solenoid valve for direct control that generates the optimal clutch pressure from the line pressure PL and directly controls the clutch and brake. The control valve may be used as a control linear solenoid to separately drive a control valve to generate clutch pressure and control the clutch and brake. As the “second switching device”, the switching of the supply of the SL3 pressure to the clutch C3 and the supply of the brake B2 and the supply of the reverse pressure to the brake B2 and the shutoff are performed by the single switching valve 60. The switching is not limited, and separate switching valves may be used for the former switching and the latter switching. 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 same as that of the embodiment described in the column of means for solving the problem. It is an example for specifically explaining the best mode for doing so, and does not limit the elements of the invention described in the column of means for solving the problem. That is, the interpretation of the invention described in the column of means for solving the problems should be made based on the description of the column, and the examples are those of the invention described in the column of means for solving the problems. It's just a concrete example

  The embodiments of the present invention have been described using the embodiments. However, the present invention is not limited to these embodiments, and can be implemented in various forms without departing from the gist of the present invention. Of course you get.

  The present invention is applicable to the automobile industry.

  10 automobile, 12 engine, 14 crankshaft, 16 engine electronic control unit (engine ECU), 18a, 18b axle, 19a, 19b wheel, 20 automatic transmission, 21 input shaft, 22 output shaft, 24 torque converter, 24a pump Impeller, 24b Turbine runner, 26 Transmission mechanism, 27 Gear mechanism, 28 Differential gear, 29 Electronic control unit for transmission (ATECU), 30 Single pinion planetary gear mechanism, 31 Sun gear, 32 Ring gear, 33 Pinion gear, 34 Carrier, 35 Ravigneaux type planetary gear mechanism, 36a, 36b Sun gear, 37 Ring gear, 38a Short pinion gear, 38b Long pinion gear, 39 Carrier, 40 Hydraulic circuit, 42 Strainer, 44 Mechanical oil , 46 Regulator valve, 48 Manual valve, 48a Input port, 48b D position output port, 48c R position output port, 51 Line pressure oil passage, 52 Drive pressure oil passage, 53 Reverse pressure oil passage, 54 SL3 pressure oil Passage, 55 C3 oil passage, 56 B2 oil passage, 60 switching valve, 62 sleeve, 62a signal pressure input port, 62b, 62c input port, 62d, 62e output port, 64 spool, 66 spring, 70 main electronic control unit (Main ECU), 81 shift lever, 82 shift position sensor, 83 accelerator pedal, 84 accelerator pedal position sensor, 85 brake pedal, 86 brake switch, 88 vehicle speed sensor, C1-C3 clutch, B1, B2 brake G, SL1-SL4, SLT Linear solenoid valve, S1 on-off solenoid valve, F1 one-way clutch.

Claims (4)

A control device for an automatic transmission that is mounted on a vehicle equipped with a prime mover and that engages a first friction engagement element and a second friction engagement element with a predetermined engagement pressure when the shift position is a reverse position. There,
When the shift position is a predetermined position including a forward position other than the reverse position, the standby pressure is set so as to be lower as the engagement pressure and higher as the vehicle speed is lower, and the standby pressure is set with the set standby pressure. A control device for an automatic transmission, wherein the frictional engagement element of 1 is placed on standby. A control device for an automatic transmission according to claim 1,
Control of an automatic transmission characterized in that when the vehicle speed is less than a predetermined vehicle speed, the standby pressure is set to increase as the vehicle speed decreases, and when the vehicle speed is equal to or higher than the predetermined vehicle speed, a value of 0 is set as the standby pressure. apparatus. A control device for an automatic transmission according to claim 2,
The control device for an automatic transmission, wherein the standby pressure is set as a lower limit pressure at which the first friction engagement element has a torque capacity. As an automatic transmission, a pump that operates by power from the prime mover and pumps hydraulic oil to a pump oil passage, and a pressure regulator that inputs and regulates the hydraulic pressure of the pump oil passage and outputs the pressure to a pressure adjustment oil passage. When the shift operation is shifted to a position other than the reverse drive position in conjunction with the shift operation, the communication between the pump oil passage and the reverse drive oil passage is cut off and the shift operation is performed to the reverse drive position. Is a first switch that communicates the pump oil passage with the reverse oil passage, and a first switch that communicates with the reverse oil passage, the pressure adjusting oil passage, and the oil chamber of the first friction engagement element. When the shift oil is connected to a first engagement oil passage and a second engagement oil passage communicating with the oil chamber of the second friction engagement element and is shifted to a position other than the reverse drive position, the reverse drive is performed. The communication between the oil passage and the first engagement oil passage is blocked. In addition, when the pressure adjusting oil passage and the first engagement oil passage are communicated and shifted to the reverse position, the reverse oil passage and the first engagement oil passage are communicated. A control device for an automatic transmission according to any one of claims 1 to 3, further comprising a second switch that communicates the pressure adjusting oil passage and the second engagement oil passage. ,
When the shift position is a position other than the reverse position, the pressure regulator is driven and controlled so that the first friction engagement element stands by at the standby pressure, and the shift position is shifted from the position other than the reverse position to the reverse position. When operated, the pressure regulator is driven and controlled so that the engagement of the second frictional engagement element is started after waiting for the engagement of the first frictional engagement element. Control device for automatic transmission.

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