JP2017180725A - Gear change device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the deterioration of fuel economy, in a gear change device having a pressure accumulator which can accumulate hydraulic pressure from a pump which is operated by the power of an engine.SOLUTION: At the establishment of an automatic start condition of an engine, when an engine rotational speed Ne is lower than an accumulator hydraulic pressure discharge prohibition threshold Neref (S160), hydraulic pressure which is accumulated in the accumulator is discharged to a line pressure oil passage by valve-opening an on/off-solenoid valve (S170), and the engagement control of a clutch or the like which should be engaged is performed by using the hydraulic pressure of the accumulator (S180). When the engine rotational speed Ne is not lower than the accumulator hydraulic pressure discharge prohibition threshold Neref (S160), the hydraulic pressure accumulated in the accumulator is held without valve-opening the on/off-solenoid valve, and the engagement control of the clutch or the like which should be engaged is performed by using the hydraulic pressure from the oil pump which is in an operation (S180).SELECTED DRAWING: Figure 5

Description

  The invention of the present disclosure disclosed in the present specification relates to a transmission.

  Conventionally, as this type of transmission, an oil pump that is operated by power from an engine, a forward clutch that is connected to the oil pump via an oil passage, and an accumulator that is provided in a branch oil passage that branches from the oil passage (Patent Document 1) has been proposed which includes a (pressure accumulator) and a hydraulic control device having a switching valve capable of blocking between an accumulator and an oil passage. In this transmission, the hydraulic pressure from the oil pump is accumulated in the accumulator by opening the switching valve during engine operation, and the accumulated hydraulic pressure is retained in the accumulator by closing the switching valve when the engine is stopped. The hydraulic pressure accumulated in the accumulator is supplied to the forward clutch by opening the switching valve at the start. Further, during engine operation, the accumulator pressure accumulation state is detected, and when it is determined that the accumulator is not accumulating hydraulic pressure based on the detected pressure accumulation state, engine stop is prohibited.

JP 2000-313252 A

  In the above-described transmission, even when the engine stop and the engine restart are switched in a short time, the switching valve is always opened and the hydraulic pressure of the accumulator is released when the engine is restarted. However, it takes time for the engine speed to decrease and the engine to stop after the engine stop command is issued. During this time, the oil pump is driven by the rotation of the engine. In a situation where an engine restart command is issued immediately after the engine stop command, even if a sufficient oil pressure can be secured by driving the oil pump, the hydraulic pressure accumulated in the accumulator is supplied to the forward clutch. For this reason, unnecessary accumulator hydraulic pressure is released, and the engine operation must be continued only for accumulating the hydraulic pressure in the accumulator, resulting in deterioration of fuel consumption.

  A transmission device according to the present disclosure is provided with a pressure accumulator capable of accumulating hydraulic pressure from a pump that is operated by power of an engine.

  The invention of the present disclosure has taken the following means in order to achieve the main object described above.

The transmission according to the present disclosure includes:
A transmission that is mounted on a vehicle having an engine capable of automatic stop and automatic start, and that transmits power from the engine to a drive wheel by changing the speed by a gear stage that is changed by engagement / disengagement of a plurality of engagement elements. There,
A pump that generates hydraulic pressure using power from the engine, and a pressure accumulator that can store and hold the hydraulic pressure from the pump, and controls the hydraulic pressure from the pump or the accumulator to control the engagement. A hydraulic control device capable of supplying a combined component hydraulic servo;
When starting the engine with a request for traveling, if the engine speed is less than a threshold value, the hydraulic pressure accumulated in the pressure accumulator is released and the hydraulic servo of a predetermined engagement element is used. The hydraulic control device is controlled so that hydraulic pressure is supplied, and when the engine rotation speed is equal to or higher than the threshold value, the hydraulic servo of the predetermined engagement element is maintained while the hydraulic pressure accumulated in the pressure accumulator is held. Control means for controlling the hydraulic control device so that the hydraulic pressure is supplied to
It is a summary to provide.

  In the transmission according to the present disclosure, when the engine is started with a request for travel, when the engine speed is less than the threshold value, the engagement to be engaged in a state in which the hydraulic pressure accumulated in the pressure accumulator is released. The hydraulic control device is controlled so that the hydraulic pressure is supplied to the hydraulic servo of the element, and when the engine rotation speed is equal to or higher than the threshold value, the engagement element to be engaged with the hydraulic pressure accumulated in the pressure accumulator is held. The hydraulic control device is controlled so that the hydraulic pressure is supplied to the hydraulic servo. Thus, for example, when the start condition is satisfied immediately after the engine stop condition is satisfied and before the engine speed falls below the threshold value, the engagement element is engaged by the hydraulic pressure from the pump driven by the power from the engine. Therefore, it is possible to suppress the wasteful release of the hydraulic pressure accumulated in the pressure accumulator. As a result, when the engine stop condition is satisfied, it is not necessary to prohibit the engine stop just for accumulating the hydraulic pressure in the pressure accumulator, so that deterioration of fuel consumption can be suppressed.

It is a block diagram which shows the outline of a structure of the motor vehicle 10 carrying the transmission 20 which concerns on embodiment of invention of this indication. 1 is a configuration diagram showing an outline of a mechanical configuration of a transmission 20 including an automatic transmission 25. It is explanatory drawing which shows the operation | movement table | surface showing the relationship between each gear stage of the automatic transmission 25, and the operation state of clutch C1-C4, brake B1, B2, and the one-way clutch F1. FIG. 2 is a configuration diagram showing an outline of a configuration of a hydraulic control device 60. 5 is a flowchart illustrating an example of a start time control routine executed by a transmission ECU 80. It is explanatory drawing which shows the relationship between the oil temperature Toil and the accumulator oil pressure discharge | release prohibition threshold value Neref. It is explanatory drawing which shows the mode of engagement control in case the automatic start conditions of the engine 12 are satisfied when the engine speed Ne is more than the accumulator oil pressure release prohibiting threshold Neref. It is explanatory drawing which shows the mode of engagement control in case the automatic start conditions of the engine 12 are satisfied when the engine speed Ne is less than the accumulator hydraulic pressure release prohibition threshold Neref.

  Next, embodiments for carrying out the present invention will be described with reference to the drawings.

  FIG. 1 is a configuration diagram showing an outline of a configuration of an automobile 10 equipped with a transmission 20 according to an embodiment of the present disclosure. FIG. 2 is an outline of a mechanical configuration of the transmission 20 including an automatic transmission 25. FIG.

  As shown in FIGS. 1 and 2, the automobile 10 includes an engine 12, an engine electronic control unit (hereinafter referred to as an engine ECU) 16 that controls the operation of the engine 12, and a fluid attached to a crankshaft 14 of the engine 12. The input shaft 26 is connected to the transmission device 23 and the output side of the fluid transmission device 23, and the output shaft 28 is connected to the drive wheels 18 a and 18 b via the gear mechanism 42 and the differential gear 44 and input to the input shaft 26. A stepped automatic transmission 25 that shifts the transmitted power to the output shaft 28, a hydraulic control device 60 that supplies hydraulic fluid to the fluid transmission device 23 and the automatic transmission 25, and the hydraulic control device 60. A transmission electronic control unit (hereinafter referred to as a transmission ECU) 80 for controlling the fluid transmission device 23 and the automatic transmission 25 by means of a power transmission device (not shown). Controlled hydraulic brake electronic control unit which controls the brake unit (hereinafter, brake as ECU) includes a 17, a. Here, the transmission 20 mainly corresponds to the automatic transmission 25, the hydraulic control device 60, and the transmission ECU 80.

  The engine ECU 16 is configured as a microprocessor centered on a CPU, and includes a ROM that stores a processing program, a RAM that temporarily stores data, an input / output port, and a communication port in addition to the CPU. The engine ECU 16 detects signals from various sensors for detecting the operating state of the engine 12, such as a crank angle θ from a crank angle sensor 14a attached to the crankshaft 14, and an accelerator opening Acc as an amount of depression of an accelerator pedal 91. Signals such as the accelerator opening Acc from the accelerator pedal position sensor 92 and the vehicle speed V from the vehicle speed sensor 98 are input via the input port. The engine ECU 16 calculates the engine speed Ne based on the crank angle θ from the crank angle sensor 14a. The engine ECU 16 outputs a drive signal to the throttle motor that drives the throttle valve, a control signal to the fuel injection valve, an ignition signal to the spark plug, and the like via the output port.

  As shown in FIG. 2, the fluid transmission device 23 is configured as a fluid torque converter with a lock-up clutch including a pump impeller, a turbine runner, a stator, a one-way clutch, a lock-up clutch, and the like.

  The automatic transmission 25 is configured as an 8-speed transmission, and as shown in FIG. 2, a double pinion type first planetary gear mechanism 30, a Ravigneaux type second planetary gear mechanism 35, and an input side. Four clutches C1, C2, C3 and C4 for changing the power transmission path to the output side, two brakes B1 and B2, and a one-way clutch F1 are provided.

  The first planetary gear mechanism 30 of the automatic transmission 25 is engaged with a sun gear 31 that is an external gear and a ring gear 32 that is an internal gear disposed concentrically with the sun gear 31 and one of the first gear mechanism 30 and the sun gear 31. The other includes a planetary carrier 34 that holds a plurality of sets of two pinion gears 33a and 33b meshing with the ring gear 32 so as to be rotatable (rotatable) and revolved. As illustrated, the sun gear 31 of the first planetary gear mechanism 30 is fixed to the transmission case 22, and the planetary carrier 34 of the first planetary gear mechanism 30 is coupled to the input shaft 26 so as to be integrally rotatable. The first planetary gear mechanism 30 is configured as a so-called reduction gear, and decelerates the power transmitted to the planetary carrier 34 as an input element and outputs it from a ring gear 32 as an output element.

  The second planetary gear mechanism 35 of the automatic transmission 25 is an internal gear disposed concentrically with the first sun gear 36a and the second sun gear 36b, which are external gears, and the first and second sun gears 36a and 36b. Ring gear 37, a plurality of short pinion gears 38a meshing with first sun gear 36a, a plurality of long pinion gears 38b meshing with second sun gear 36b and a plurality of short pinion gears 38a and meshing with ring gear 37, a plurality of short pinion gears 38a and It has a planetary carrier 39 for holding a plurality of long pinion gears 38b so as to be rotatable (rotatable) and revolved. The ring gear 37 of the second planetary gear mechanism 35 functions as an output member of the automatic transmission 25, and the power transmitted from the input shaft 26 to the ring gear 37 is transmitted to the left and right drive wheels 18a via the gear mechanism 42 and the differential gear 44. , 18b. The planetary carrier 39 is supported by the transmission case 22 via the one-way clutch F1, and the rotation direction of the planetary carrier 39 is limited to one direction by the one-way clutch F1.

  Each of the clutches C1 to C4 has a hydraulic servo constituted by a piston, a plurality of friction plates and separator plates, an oil chamber to which hydraulic oil is supplied, and the like, and connects the two rotating systems to each other. It is configured as a frictional hydraulic clutch that can be released. The clutch C1 can connect the ring gear 32 of the first planetary gear mechanism 30 and the first sun gear 36a of the second planetary gear mechanism 35 to each other and release the connection therebetween. The clutch C2 is capable of connecting the input shaft 26 and the planetary carrier 39 of the second planetary gear mechanism 35 to each other and releasing the connection therebetween. The clutch C3 can connect the ring gear 32 of the first planetary gear mechanism 30 and the second sun gear 36b of the second planetary gear mechanism 35 to each other and release the connection therebetween. The clutch C4 can connect the planetary carrier 34 of the first planetary gear mechanism 30 and the second sun gear 36b of the second planetary gear mechanism 35 to each other and release the connection therebetween.

  Each of the brakes B1 and B2 has a hydraulic servo constituted by a plurality of friction plates, separator plates, an oil chamber supplied with hydraulic oil, etc., and connects the rotating system to the fixed system and releases the connection. It is configured as a possible friction-type hydraulic brake. The brake B1 can fix the second sun gear 36b of the second planetary gear mechanism 35 to the transmission case 22 in a non-rotatable manner and can release the second sun gear 36b from being fixed to the transmission case 22. The brake B2 can fix the planetary carrier 39 of the second planetary gear mechanism 35 to the transmission case 22 in a non-rotatable manner and can release the fixation of the planetary carrier 39 to the transmission case 22.

  The one-way clutch F1 is disposed between the inner race connected to (fixed to) the planetary carrier 39 of the second planetary gear mechanism 35, the outer race fixed to the transmission case 22, and the inner race and the outer race. A torque transmission member (a plurality of sprags, etc.) is provided, and only rotation in one direction of the planetary carrier 39 is allowed.

  The clutches C1 to C4 and the brakes B1 and B2 operate by receiving hydraulic oil supplied and discharged by the hydraulic control device 60. 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 C4, the brakes B1 and B2, and the one-way clutch F1. The automatic transmission 25 provides the forward 1st to 8th gears and the reverse 1st and 2nd gears by setting the clutches C1 to C4 and the brakes B1 and B2 to the states shown in the operation table of FIG. . Specifically, as shown in FIG. 3, the first forward speed is formed by engaging the clutch C1. In the first forward speed, the brake B2 is also engaged during engine braking. The second forward speed is formed by engaging the clutch C1 and the brake B1. The third forward speed is formed by engaging the clutch C1 and the clutch C3. The fourth forward speed is formed by engaging the clutch C1 and the clutch C4. The fifth forward speed is formed by engaging the clutch C1 and the clutch C2. The sixth forward speed is formed by engaging the clutch C2 and the clutch C4. The seventh forward speed is formed by engaging the clutch C2 and the clutch C3. The eighth forward speed is formed by engaging the clutch C2 and the brake B1. The first reverse speed is formed by engaging the clutch C3 and the brake B2. The second reverse speed is formed by engaging the clutch C4 and the brake B2.

  The hydraulic control device 60 adjusts the oil pump 61 that pumps hydraulic oil by the power of the engine 12 and supplies a part of the hydraulic oil pumped by the oil pump 61 to a lubrication target 72 such as a cooler 71, gears, and bearings. A regulator valve 62 that generates a line pressure PL in the line pressure oil passage 63 and a linear solenoid that regulates the line pressure PL in the line pressure oil passage 63 and supplies it to the hydraulic servos of the clutches C1 to C4 and the brakes B1 and B2. Valves SLC1 to SLC4, SLB1 and SLB2 (SLC2 to 4 and SLB1 are not shown), an accumulator 64 as an accumulator for accumulating hydraulic pressure from the oil pump 61, an accumulator 64 and an oil passage 63 for line pressure An on-off solenoid valve 65 that performs communication and shut-off, and a parking lock device are provided. It includes a parking cylinder 66 for driving the king pole, the on-off solenoid valve 67 to perform the blocking and communication between the line pressure oil passage 63.

  In this embodiment, the parking lock device includes a parking gear, a parking pole, a spring, a parking cylinder 66, and the like provided on the rotating shaft of the automatic transmission 25, and performs parking lock and release thereof by a hydraulic actuator. It is configured as a shift-by-wire parking lock device. The parking pole is engaged with the parking gear by being pressed against the parking gear by the urging force of the spring, and is disengaged from the parking gear by being driven by the parking cylinder 66 using the line pressure PL. Since the parking cylinder 66 is connected to the accumulator 64 through the on / off solenoid valve 67, the line pressure oil passage 63, and the on / off solenoid valve 65, the parking lock is released using the hydraulic pressure accumulated in the accumulator 64. Can do.

  The transmission ECU 80 is configured as a microprocessor centered on a CPU, and includes a ROM that stores a processing program, a RAM that temporarily stores data, an input / output port, and a communication port in addition to the CPU. . The transmission ECU 80 includes an accumulator internal pressure Pacc from the pressure sensor 64a that detects the pressure in the accumulator 64, an oil temperature Toil from the oil temperature sensor 68 that detects the oil temperature of the hydraulic oil in the hydraulic control device 60, and a shift lever. The shift position SP from the shift position sensor 96 for detecting the position 95, the switch signal from the snow mode switch 97 for starting at the second forward speed or making the timing of the shift change earlier than usual, the vehicle speed from the vehicle speed sensor 98 V or the like is input through the input port. On the other hand, the transmission ECU 80 outputs control signals to the hydraulic control device 60 (linear solenoid valves SLC1, SLB2, on / off solenoid valves 65, 67) through an output port.

  In this embodiment, the shift position SP of the shift lever 95 includes a parking position (P position) used during parking, a reverse position (R position) for reverse travel, a neutral position (N position), and forward travel. The normal drive position (D position) is prepared. When the shift lever 95 is shifted to the parking position, the transmission ECU 80 closes the on / off solenoid valve 67 and shuts off the supply of hydraulic pressure to the parking cylinder 66, so that the parking pole is driven by the biasing force of the spring. Is engaged with the parking gear to perform parking lock. Further, when the shift lever 95 is shifted from the parking position to another position, the on / off solenoid valve 67 is opened to supply hydraulic pressure to the parking cylinder 66, thereby driving the parking pole and the parking pole and the parking gear. And the parking lock is released.

  The engine ECU 16, the brake ECU 17, and the transmission ECU 80 are connected to each other via a communication port, and exchange various control signals and data necessary for control with each other. The transmission ECU 80 inputs the engine rotational speed Ne calculated based on the crank angle θ from the crank angle sensor 14a and the accelerator opening degree Acc from the accelerator pedal position sensor 92 via communication via the engine ECU 16, or the brake pedal. The brake opening B from the brake pedal position sensor 94 that detects the amount of depression 93 is input via communication via the brake ECU 17.

  In the vehicle 10 configured in this way, the engine ECU 16 causes the fuel to be supplied to the engine 12 when the automatic stop condition of the engine 12 is satisfied and the automatic stop is permitted, such as when the vehicle speed V is less than a predetermined vehicle speed and the accelerator is off. Idling stop control is performed in which the supply is stopped and automatically stopped, and the engine 12 is cranked and automatically started when automatic start conditions of the engine 12 such as brake-off and accelerator-on are satisfied.

  The transmission ECU 80 opens the on / off solenoid valve 65 when the engine 12 is in operation, accumulates the hydraulic pressure from the oil pump 61 operated by the power of the engine 12 in the accumulator 64, and turns on / off when the engine 12 is automatically stopped. The solenoid valve 65 is closed to hold the hydraulic pressure accumulated in the accumulator 64.

  Further, the transmission ECU 80 detects the hydraulic pressure (accumulator internal pressure Pacc) accumulated in the accumulator 64 during operation of the engine 12 by the pressure sensor 64a, and waits for the detected accumulator internal pressure Pacc to be equal to or higher than the threshold value. An automatic stop permission signal for permitting the automatic stop of 12 is transmitted to the engine ECU 16. The engine ECU 16 does not automatically stop the engine 12 until an automatic stop permission signal is received (automatic stop is permitted) even if the automatic stop condition of the engine 12 is satisfied. That is, after the engine 12 is automatically stopped, the next time the engine 12 is started to run (start), a clutch or the like to be engaged (for example, the clutch C1 when traveling at the first forward speed, Preparation for engaging the clutch C1 and the brake B1 when traveling in the second forward speed, and the clutch C3 and the brake B2 when traveling in the first reverse speed (preparation for engagement) The accumulator internal pressure (stop permission threshold) that permits the automatic stop of the engine 12 is set so that the hydraulic pressure required for the accumulator 64 can be supplied by the accumulator 64, and the accumulator internal pressure Pacc from the pressure sensor 64a is the stop permission threshold. When it becomes above, an automatic stop permission signal is transmitted to engine ECU16. Note that preparation for engagement includes, for example, control in which hydraulic oil such as a clutch to be engaged is filled with hydraulic oil and the piston is held near the stroke end. Here, since the hydraulic pressure accumulated in the accumulator 64 gradually decreases with the passage of time due to leakage of hydraulic oil, the stop permission threshold is, for example, a standard stop of the engine 12 after the engine 12 is automatically stopped. Even if time elapses, the accumulator 64 is set to a value (base value) such that the hydraulic pressure necessary for the above-described preparation for engagement remains. In addition, when the shift position SP is shifted from the P position to the travel position (D position or R position) to start, the hydraulic pressure for releasing the parking lock (release) Pressure) is also required. Therefore, when the current shift position SP is the P position, the stop permission threshold is set by adding the release pressure to the base value. Further, when starting at the second forward speed or starting at the first reverse speed, the number of clutches to be engaged is larger than when starting at the first forward speed. For this reason, when the number of clutches to be engaged increases and the hydraulic pressure necessary for preparation for engagement increases, the stop permission threshold value may be further increased and set.

  Next, the operation of the transmission 20 of the present embodiment configured as described above, particularly, the operation when starting the engine 12 to start will be described. FIG. 5 is a flowchart showing an example of a start time control routine. This routine is executed by the transmission ECU 80 when the automatic start condition of the engine 12 is satisfied.

  When the starting control routine is executed, the CPU of the transmission ECU 80 first inputs data such as the engine rotational speed Ne, the shift position SP, the snow mode switch signal, and the oil temperature Toil (step S100).

  When the data is input, the accumulator hydraulic pressure release prohibiting threshold value Neref is set based on the input oil temperature Toil (step S110). Here, the accumulator hydraulic pressure release prohibition threshold value Neref indicates whether or not the hydraulic pressure from the oil pump 61 can secure the hydraulic pressure necessary for preparation for engagement of the clutch to be engaged in the current engine speed Ne. When the engine speed Ne is equal to or higher than the accumulator hydraulic pressure release prohibiting threshold Neref, the hydraulic pressure accumulated in the accumulator 64 is prohibited from being released. The accumulator oil pressure release prohibiting threshold value Neref is set by preliminarily obtaining the relationship between the oil temperature Toil and the accumulator oil pressure release prohibiting threshold value Neref and storing it in the ROM as a map, and when the oil temperature Toil is given, the corresponding accumulator oil pressure is obtained from the map. This is done by deriving the release prohibition threshold Neref. An example of this map is shown in FIG. As shown in the figure, the accumulator oil pressure release prohibiting threshold value Neref is set so as to increase as the oil temperature Toil increases. This is because in a region where the oil temperature is high, the viscosity of the oil decreases and the amount of oil leakage increases. Therefore, the higher the oil temperature, the greater the required flow rate to be supplied to the clutch to be engaged (necessary engine) The rotational speed Ne increases). Now, the case where the automatic start condition of the engine 12 is satisfied is considered, and the state of the engine 12 at the time when the automatic start condition is satisfied is a state where the fuel supply is stopped. The oil pump 61 stops operating when the engine 12 stops rotating. On the other hand, even if the automatic stop condition is satisfied and the fuel supply is stopped, the engine 12 does not immediately stop rotating, but is maintained in a rotating state for a while while gradually decreasing the rotation speed. For this reason, when the automatic start condition is satisfied immediately after the automatic stop condition of the engine 12 is satisfied, the hydraulic pressure necessary for the above-described engagement preparation may be secured by the hydraulic pressure from the oil pump 61. The process of step S110 sets the accumulator hydraulic pressure release prohibition threshold Neref in order to determine such a situation.

  Next, based on the input shift position SP, it is determined whether or not a shift operation has been performed from the P position to the travel position (D position or R position) (step S120). If it is determined that the shift operation has been performed from the P position to the traveling position, a new accumulator hydraulic pressure release prohibiting threshold value Neref is set by adding a correction value α1 to the current accumulator hydraulic pressure release prohibiting threshold value Neref (step S130). If it is determined that the shift operation is not performed, the process of step S130 is skipped. Here, the correction value α1 indicates whether or not the hydraulic pressure (release pressure) necessary for releasing the parking lock can be secured by the hydraulic pressure from the oil pump 61 in addition to the hydraulic pressure necessary for preparation for engagement. This is a correction value for determination.

  Then, it is determined whether the start stage is the second forward speed or the reverse speed (step S140). Here, whether or not the start stage is the second forward speed is determined by determining whether or not the shift position SP is the D position and the snow mode switch signal is ON. The determination as to whether or not the vehicle is in the reverse speed is made by determining whether or not the shift position SP is the R position. If it is determined that the starting stage is the second forward speed or the reverse stage, a new accumulator hydraulic pressure release prohibiting threshold value Neref is set by adding the correction value α2 to the current accumulator hydraulic pressure releasing prohibiting threshold value Neref (step S150), and the starting stage. Is determined not to be the second forward speed or the reverse speed, that is, the first forward speed, the process of step S150 is skipped. Here, the correction value α2 is used to determine whether or not the hydraulic pressure required for each engagement preparation can be secured by the hydraulic pressure from the oil pump 61 when there are two clutches or the like to be engaged. Is the correction value.

  When the accumulator hydraulic pressure release prohibiting threshold value Neref is set in this manner, it is determined whether or not the input engine speed Ne is less than the accumulator hydraulic pressure release prohibiting threshold value Neref (step S160), and the engine rotational speed Ne is less than the accumulator hydraulic pressure release prohibiting threshold value Neref. When it is determined that the on-off solenoid valve 65 is opened so that the hydraulic pressure accumulated in the accumulator 64 is released (step S170), the engagement control of the clutch to be engaged is executed (step S180), The starting control routine is terminated. On the other hand, if it is determined that the engine rotational speed Ne is equal to or higher than the accumulator hydraulic pressure release prohibiting threshold Neref, the clutch to be engaged, etc., with the hydraulic pressure accumulated in the accumulator 64 held without opening the on / off solenoid valve 65. Is executed (step S180), and the starting control routine is terminated.

  7 and 8 are explanatory diagrams showing the state of engagement control. 7 shows a state of engagement control when the automatic start condition of the engine 12 is satisfied when the engine rotational speed Ne is equal to or higher than the accumulator hydraulic pressure release prohibiting threshold Neref. FIG. 8 shows the engine rotational speed Ne when the engine rotational speed Ne is the accumulator. The state of engagement control when the automatic start condition of the engine 12 is satisfied when the hydraulic pressure release prohibition threshold value Neref is less than the value will be described. Hereinafter, the engagement control when the clutch C1 is engaged to form the first forward speed will be described. As shown in FIG. 7, when the automatic start condition of the engine 12 is satisfied when the engine speed Ne is equal to or greater than the accumulator hydraulic pressure release prohibition threshold Neref (time t1), the clutch C1 is in a state immediately before engagement (for example, the clutch C1 Filling control (fast fill control) for rapidly filling the hydraulic servo of the clutch C1 with hydraulic oil is executed so that the piston reaches the stroke end (time t2). The filling control is performed by driving and controlling the linear solenoid valve SLC1 corresponding to the clutch C1 with a relatively high duty ratio. When the filling control is executed for a predetermined time, the standby control for holding the hydraulic pressure to the hydraulic servo of the clutch C1 at a relatively low standby pressure is performed by controlling the driving of the linear solenoid valve SLC1 with a relatively low duty ratio (time t3). ). When the engine rotational speed Ne reaches a predetermined rotational speed Neset at which the clutch C1 can be completely engaged (time t4), the linear solenoid valve SLC1 is driven and controlled so that the hydraulic pressure applied to the hydraulic servo of the clutch C1 gradually increases. The boost control is executed to fully engage the clutch C1. If the automatic start condition of the engine 12 is satisfied when the engine rotational speed Ne is equal to or higher than the accumulator hydraulic pressure release prohibiting threshold Neref, the on / off solenoid valve 65 is closed and the hydraulic pressure is not released from the accumulator 64. As a result, filling control, standby control, and pressure increase control are executed using only the hydraulic pressure from the oil pump 61. On the other hand, as shown in FIG. 8, when the automatic start condition of the engine 12 is satisfied when the engine rotational speed Ne is less than the accumulator hydraulic pressure release prohibition threshold Neref (time t11), the on / off solenoid valve 65 is opened, and the accumulator 64 starts. After releasing the hydraulic pressure (time t12), the filling control is executed (time t13). When the filling control is executed for a predetermined time, standby control is executed (time t14). When the engine rotational speed Ne reaches the predetermined rotational speed Neset (time t15), the boost control is executed to fully engage the clutch C1. . Thus, when the engine rotational speed Ne is less than the accumulator hydraulic pressure release prohibiting threshold Neref, the hydraulic pressure accumulated in the accumulator 64 is released, and filling control and standby control are executed using the released hydraulic pressure. As the engagement control using the hydraulic pressure accumulated in the accumulator 64, control is performed so that the hydraulic pressure is supplied to the hydraulic servo until the friction material (friction plate, separator plate) is completely engaged without slipping. Alternatively, control may be performed so that the hydraulic pressure is supplied to the hydraulic servo until the friction material is engaged (semi-engaged) with sliding. The same applies to the case where the brake B1 is engaged in addition to the clutch C1 to form the second forward speed, and the case where the clutch C3 and the brake B2 are engaged to form the first reverse speed. be able to.

  According to the transmission 20 of the present disclosure described above, when the automatic start condition of the engine 12 is satisfied, the on / off solenoid valve 65 is opened when the rotational speed Ne of the engine 12 is less than the accumulator hydraulic pressure release prohibition threshold Neref. The hydraulic pressure accumulated in the accumulator 64 is discharged to the line pressure oil passage 63, and the engagement control of the clutch and the like to be engaged is performed using the hydraulic pressure of the accumulator 64. When the rotational speed Ne of the engine 12 is equal to or higher than the accumulator hydraulic pressure release prohibiting threshold Neref, the hydraulic pressure accumulated in the accumulator 64 is maintained without opening the on / off solenoid valve 65, and the hydraulic pressure from the oil pump 61 in operation is maintained. Engagement control of the clutch etc. to be engaged is performed. Thereby, useless discharge | release of the hydraulic pressure accumulated in the accumulator 64 can be prevented. As a result, it is not necessary to prohibit the stop of the engine 12 just for accumulating the hydraulic pressure in the accumulator 64 when the automatic stop condition of the engine 12 is satisfied next time, so that deterioration of fuel consumption can be suppressed.

  Further, according to the transmission 20 of the present disclosure, the accumulator hydraulic pressure release prohibition threshold value Neref is set based on the oil temperature Toil, so that the hydraulic pressure necessary for the engagement control of the clutch to be engaged can be pumped from the oil pump 61. It can be determined appropriately according to the viscosity of the hydraulic oil whether it can be ensured by a proper hydraulic pressure. As a result, it is possible to prevent the hydraulic pressure accumulated in the accumulator 64 from being discharged unnecessarily, and to realize quick and smooth engagement such as a clutch to be engaged.

  Furthermore, according to the transmission 20 of the present disclosure, a shift operation is performed from the P position to the travel position (D position or R position) when the parking lock can be released by supplying the hydraulic pressure of the accumulator 64 to the parking cylinder 66. When the automatic start condition of the engine 12 is satisfied, the accumulator hydraulic pressure release prohibiting threshold value Neref with the correction value α1 added is set. Therefore, in addition to the hydraulic pressure necessary for the engagement control of the clutch to be engaged, the parking It is possible to appropriately determine whether or not the release pressure for releasing the lock can be secured by the hydraulic pressure that can be pumped from the oil pump 61.

  In addition, according to the transmission 20 of the present disclosure, when engaging a plurality of clutches at the time of starting, the accumulator hydraulic pressure release prohibiting threshold value Neref with the correction value α2 added is set. When the oil pressure required for each of the oil pressures is larger than the oil pressure required for a single clutch, etc., whether or not the oil pressure can be secured by the oil pressure that can be pumped from the oil pump 61 is appropriately determined. Can be determined.

  In the transmission 20 of the present disclosure, when the shift position SP is the parking position, the accumulator hydraulic pressure release prohibiting threshold value Neref is set with the correction value α1 added. However, when the parking lock is released electrically, the parking lock For example, when the release is performed using a physical cable, the correction value α1 may not be added to the accumulator hydraulic pressure release prohibition threshold Neref even if the shift position SP is the parking position.

  In the transmission 20 according to the present disclosure, when starting at the second forward speed or the reverse speed, the accumulator hydraulic pressure release prohibiting threshold value Neref is set with the correction value α2 added, but there are a plurality of clutches to be engaged. If the required hydraulic pressure does not increase compared to the first forward speed where there is only one clutch to be engaged, for example, even if there are multiple clutches to be engaged, When the hydraulic oil filling timings such as the hydraulic servos do not overlap each other, the correction value α2 may not be added to the accumulator hydraulic pressure release prohibiting threshold Neref even at the second forward speed or the reverse speed.

  In the transmission 20 according to the present disclosure, the hydraulic pressure accumulated in the accumulator 64 (accumulator internal pressure Pacc) is detected by the pressure sensor 64 a. However, the on / off time of the on / off solenoid valve 65 and the oil temperature sensor 68 The estimation may be based on the oil temperature Toil, the line pressure PL of the line pressure oil passage 63, the line pressure command value output from the hydraulic control device 60 to the regulator valve 62, and the like.

  As described above, the speed change device 20 of the present disclosure is mounted on a vehicle (10) including an engine (12) capable of automatic stop and automatic start, and power from the engine (12) is transmitted to a plurality of units. A transmission (20) that shifts by a gear stage changed by engagement / disengagement of coupling elements (C1 to C4, B1, B2) and transmits the transmission to driving wheels, and uses hydraulic power from the engine (12). And a pressure accumulator (64) capable of accumulating and holding the hydraulic pressure from the pump (61), and the hydraulic pressure from the pump (61) or the accumulator (64) When controlling the hydraulic control device (60) that can be supplied to the hydraulic servo of the engagement elements (C1 to C4, B1, B2) and starting the engine (12) with a travel request, The rotational speed of the engine (12) is less than a threshold value Sometimes, the hydraulic pressure control device (60) is controlled so that the hydraulic pressure is supplied to the hydraulic servo of a predetermined engagement element (C1) in a state where the hydraulic pressure accumulated in the pressure accumulator (64) is released, When the rotational speed of the engine (12) is equal to or greater than the threshold value, the hydraulic pressure is supplied to the hydraulic servo of the predetermined engagement element (C1) while the hydraulic pressure accumulated in the accumulator (64) is held. And a control means (80) for controlling the hydraulic control device (60).

  According to the transmission 20 of the present disclosure, when the engine (12) is started with a request for traveling and the rotational speed of the engine (12) is less than a threshold, the hydraulic pressure accumulated in the pressure accumulator (64). The hydraulic pressure control device (60) is controlled so that the hydraulic pressure is supplied to the hydraulic servo of the engagement element (C1) to be engaged in the released state, and when the rotational speed of the engine (12) is equal to or higher than the threshold value, the pressure accumulation The hydraulic pressure control device (60) is controlled so that the hydraulic pressure is supplied to the hydraulic servo of the engagement element (C1) to be engaged in a state where the hydraulic pressure accumulated in the container (64) is held. Thereby, for example, when the start condition is satisfied immediately after the stop condition of the engine (12) is established and before the rotational speed of the engine (12) falls below the threshold value, the pump from the pump operated by the power from the engine (12) is used. Since the engagement element (C1) can be engaged by the hydraulic pressure, it is possible to suppress the wasteful release of the hydraulic pressure accumulated in the pressure accumulator (64). As a result, when the stop condition of the engine (12) is satisfied, it is not necessary to prohibit the engine (12) from being stopped just for accumulating the hydraulic pressure in the accumulator (64). Deterioration can be suppressed.

  In such a transmission according to the present disclosure, the oil temperature acquisition device (68) for acquiring the temperature of the oil used in the hydraulic control device (60), and the threshold value tend to be higher as the acquired oil temperature is higher. And a threshold setting means (80) for setting. In this way, it is possible to appropriately determine whether or not the hydraulic pressure necessary for the engagement element to be engaged can be secured by the hydraulic pressure that can be pumped from the pump (61) according to the viscosity of the oil. As a result, the hydraulic pressure accumulated in the pressure accumulator (64) can be prevented from being wasted and the engagement elements to be engaged can be quickly and smoothly engaged.

  In the transmission of the present disclosure, when the shift position is the parking position, parking lock is performed so that the drive wheels do not rotate, and when the shift position is another position different from the parking position, the pump or the pressure accumulation A parking lock mechanism (66) capable of releasing the parking lock using hydraulic pressure from a container, and the threshold value to be higher when the shift operation is performed from the parking position to the travel position than in other cases. Threshold setting means (80) for setting In this way, in addition to the hydraulic pressure required for the engagement element to be engaged, whether or not the release pressure for releasing the parking lock can be secured by the hydraulic pressure that can be pumped from the pump (61) is appropriate. Can be determined.

  Furthermore, in the speed change device of the present disclosure, a start speed setting that sets a start speed, which is a speed change speed when the vehicle (10) starts, to any one of a plurality of shift speeds having different numbers of engaging elements to be engaged. In the case where the number of engaging elements engaged with the means (96, 97) and the starting stage is set to be large, the speed is set to a small number of engaging elements to be engaged. Threshold setting means (80) for setting the threshold value to be higher than the case may be provided.

  Further, the automatic transmission 25 is capable of forming the first to eighth forward speeds and the first and second reverse speeds, but is not limited to this, and is not limited to any gear stage. An automatic transmission may be used.

  Here, the correspondence between the main elements in 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 embodiment, the engine 12 corresponds to the “engine”, the oil pump 61 corresponds to the “pump”, the accumulator 64 corresponds to the “pressure accumulator”, and the hydraulic control device 60 becomes the “hydraulic control device”. The clutch C1 (when the starting stage is the first forward speed and the second forward speed), the brake B1 (when the starting stage is the second forward speed), the clutch C4 (when the starting stage is the first reverse speed), The brake B2 (when the starting speed is the first reverse speed) corresponds to the “predetermined engagement element”, and the transmission ECU 80 that executes the starting control routine corresponds to the “control means”. The oil temperature sensor 68 corresponds to the “oil temperature acquisition device”, and the transmission ECU 80 that executes the process of step S110 of the start-up control routine corresponds to the “threshold setting means”. The parking lock device including the parking cylinder 66 corresponds to a “parking lock mechanism”, and the transmission ECU 80 that executes the processes of steps S120 and S130 of the start-up control routine corresponds to a “threshold setting unit”. Further, the shift lever 95 and the snow mode switch 97 correspond to “start stage setting means”, and the transmission ECU 80 that executes the processing of steps S140 and S150 of the start time control routine corresponds to “threshold setting means”.

  As described above, the embodiment of the present disclosure has been described using examples. However, the invention of the present disclosure is not limited to these examples, and various modifications can be made without departing from the gist of the invention of the present disclosure. Of course, it can be implemented in the form.

  The present invention can be used in the transmission industry and the like.

  10 automobiles, 12 engines, 14 crankshafts, 14a crank angle sensors, 16 engine ECUs, 17 brake ECUs, 18a, 18b drive wheels, 20 transmissions, 22 transmission cases, 23 fluid transmissions, 25 automatic transmissions, 26 input shafts , 28 output shaft, 30 first planetary gear mechanism, 31 sun gear, 32 ring gear, 33a, 33b pinion gear, 34 planetary carrier, 35 second planetary gear mechanism, 36a first sun gear, 36b second sun gear, 37 ring gear, 38a short pinion gear 38b Long pinion gear, 39 Planetary carrier, 42 Gear mechanism, 44 Differential gear, 60 Hydraulic control device, 61 Oil pump, 62 Regulator valve, 63 Line pressure oil passage, 64 Aki Compressor, 64a Pressure sensor, 65 On / off solenoid valve, 66 Parking cylinder, 67 On / off solenoid valve, 68 Oil temperature sensor, 71 Cooler, 72 Lubrication target, 80 Transmission ECU, 91 Accelerator pedal, 92 Accelerator pedal position sensor, 93 Brake pedal 94 brake pedal position sensor, 95 shift lever, 96 shift position sensor, 97 travel mode switch, 98 vehicle speed sensor, C1-C4 clutch, B1, B2 brake, F1 one-way clutch, SLC1-SLC4, SLB1, SLB2 linear solenoid valve.

Claims (4)

A transmission that is mounted on a vehicle having an engine capable of automatic stop and automatic start, and that transmits power from the engine to a drive wheel by changing the speed by a gear stage that is changed by engagement / disengagement of a plurality of engagement elements. There,
A pump that generates hydraulic pressure using power from the engine, and a pressure accumulator that can store and hold the hydraulic pressure from the pump, and controls the hydraulic pressure from the pump or the accumulator to control the engagement. A hydraulic control device capable of supplying a combined component hydraulic servo;
When starting the engine with a request for traveling, if the engine speed is less than a threshold value, the hydraulic pressure accumulated in the pressure accumulator is released and the hydraulic servo of a predetermined engagement element is used. The hydraulic control device is controlled so that hydraulic pressure is supplied, and when the engine rotation speed is equal to or higher than the threshold value, the hydraulic servo of the predetermined engagement element is maintained while the hydraulic pressure accumulated in the pressure accumulator is held. Control means for controlling the hydraulic control device so that the hydraulic pressure is supplied to
A transmission comprising: The transmission according to claim 1, wherein
An oil temperature acquisition device for acquiring the temperature of the oil used in the hydraulic control device;
Threshold setting means for setting the threshold in a tendency to increase as the temperature of the acquired oil increases;
A transmission comprising: The transmission according to claim 1 or 2,
When the shift position is the parking position, parking lock is executed so that the driving wheel does not rotate. When the shift position is another position different from the parking position, the parking using the hydraulic pressure from the pump or the pressure accumulator is performed. A parking lock mechanism that can be unlocked;
A threshold value setting means for setting the threshold value to be higher when the shift operation is performed from the parking position to the travel position;
A transmission comprising: The transmission according to any one of claims 1 to 3,
Start stage setting means for setting a start stage, which is a shift stage when the vehicle starts, to any one of a plurality of shift stages having different numbers of engaging elements;
When the gear position is set to have a large number of engaging elements to be engaged as the starting speed, the speed is higher than when the gear position is set to have a small number of engaging elements to be engaged. Threshold value setting means for setting the threshold value,
A transmission comprising:

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