JP2016017528A - Automatic transmission control unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an automatic transmission control unit capable of suppressing an engagement delay, an engagement shock, and the like of friction elements when an N→D selection operation is performed while an engine is automatically stopped in N-range, and yet ensuring switching responsiveness to a reverse starting gear position when an N→R selection operation is performed.SOLUTION: A low clutch is engaged in an advancement FIRST gear position and disengaged in a reverse gear position. An R35 brake is disengaged in the advancement FIRST gear position and engaged in the reverse gear position. While an engine is automatically stopped by idling stop control, a waiting hydraulic pressure Pd, Pn equal to or lower than an engagement hydraulic pressure is supplied to the low clutch. At a time of restarting the engine on the basis of an N→D selection operation, the hydraulic pressure supplied to the low clutch is increased from the waiting hydraulic pressure Pn to the engagement hydraulic pressure. At a time of restarting the engine on the basis of an N→R selection operation, the waiting hydraulic pressure Pn is discharged from the low clutch and the engagement hydraulic pressure is supplied to the R35 brake. The waiting hydraulic pressure Pn in N-range is set to a value lower than the waiting hydraulic pressure Pd in D-range.SELECTED DRAWING: Figure 10

Description

  The present invention relates to an automatic transmission control device, and more particularly to an automatic transmission control device mounted on a vehicle on which idle stop control is performed.

  Conventionally, in a vehicle (idle stop vehicle) that performs an idle stop control in which an engine is automatically stopped when a predetermined stop condition is satisfied and the engine is restarted when the predetermined restart condition is satisfied in an engine automatic stop state (idle stop vehicle), In order to suppress a fastening delay of a friction element, a fastening shock, and the like, it is known that hydraulic pressure is supplied by an electric oil pump to a friction element that is fastened when the engine is restarted during automatic engine stop.

  For example, Patent Document 1 discloses that hydraulic pressure is supplied to the friction element that is fastened at the start stage during the automatic engine stop in the N range as well as the D range. Specifically, even after the vehicle stops in the D range and the range is switched from the D range to the N range after the automatic engine stop, the hydraulic pressure is supplied to the friction element that is engaged at the forward start stage (first forward speed). In the state, it is disclosed that the engine is restarted when the driver performs an N → D selection operation.

JP 2012-30779 A (particularly paragraphs 0073 to 0077, FIG. 6)

  However, the above technique assumes that the vehicle travels forward in the D range after restarting the engine and supplies the hydraulic pressure to the friction element that is fastened in the forward start stage even in the N range. When the N → R select operation is performed, the hydraulic pressure is discharged from the friction element that is fastened at the forward start stage that has been supplying hydraulic pressure until the release of the friction element, and then the reverse start stage (reverse position) It is necessary to supply hydraulic pressure to the friction element that is fastened at a high speed to fasten the friction element, and there is a problem that the response to switching to the reverse start stage is lowered.

  The present invention addresses the above-mentioned problem in an automatic transmission mounted on an idle stop vehicle. When the N → D select operation is performed while the engine is automatically stopped in the N range, the friction element is delayed or engaged. It is an object of the present invention to provide a control device for an automatic transmission that can achieve both suppression of shock and the like and ensuring of responsiveness to switching to a reverse start stage when an N → R selection operation is performed.

  In order to solve the above problems, the present invention provides a vehicle having an idle stop means for automatically stopping an engine when a predetermined stop condition is satisfied and restarting the engine when a predetermined restart condition is satisfied in an engine automatic stop state. A control device for an automatic transmission to be mounted, the first friction element being fastened at the forward start stage of the automatic transmission and released at the reverse start stage, and released and reversely started at the forward start stage of the automatic transmission. A second friction element that is fastened in stages, and a hydraulic control means that controls a hydraulic pressure for fastening the first friction element and the second friction element, wherein the hydraulic control means includes the idle stop means. During the automatic engine stop, a predetermined standby hydraulic pressure that is equal to or lower than the engagement hydraulic pressure at which the first friction element is engaged is supplied to the first friction element, and the selection from the non-travel range to the forward travel range is performed. When the engine is restarted based on the engine operation, the hydraulic pressure supplied to the first friction element is increased from the standby hydraulic pressure to the fastening hydraulic pressure, and when the engine is restarted based on the select operation from the non-traveling range to the reverse traveling range, The standby hydraulic pressure is discharged from the first friction element, and the fastening hydraulic pressure for bringing the second friction element into a fastening state is supplied to the second friction element. The standby hydraulic pressure is a range of the automatic transmission. The non-traveling range is characterized by being set to a lower value than in the forward traveling range.

  According to the present invention, when the range is selected to the forward travel range while the engine is automatically stopped in the non-travel range, the engine is restarted and the hydraulic pressure supplied to the first friction element is fastened from the standby hydraulic pressure. The pressure is increased to the hydraulic pressure, and the first friction element is in the engaged state. At this time, since the predetermined standby hydraulic pressure is supplied to the first friction element during the automatic engine stop, the first friction element is supplied as compared with the case where such hydraulic pressure is not supplied to the first friction element. The hydraulic pressure is increased to the fastening hydraulic pressure in a short time. As a result, the first friction element is quickly engaged, and the engagement delay of the first friction element at the time of engine restart, the engagement shock, and the like are suppressed.

  On the other hand, when the range is selected to the reverse travel range while the engine is automatically stopped in the non-travel range, the engine is restarted, the standby hydraulic pressure is discharged from the first friction element, and the engagement hydraulic pressure is applied to the second friction element. Is supplied, and the second friction element is brought into an engaged state. At this time, since the standby hydraulic pressure supplied to the first friction element during the automatic engine stop is lower than the standby hydraulic pressure supplied during the forward travel range, the standby hydraulic pressure from the first friction element is relatively short. To be discharged. Therefore, the supply of the engagement hydraulic pressure to the second friction element is started relatively early, and the second friction element is quickly brought into the engagement state, and the switching response to the reverse start stage is ensured.

  In the present invention, a third friction element that is fastened at both the forward start stage and the reverse start stage of the automatic transmission is provided. The third friction element includes a friction plate and a pressing piston that presses the friction plate. And a clearance adjustment piston that supports the pressing piston so as to be relatively movable. When the first hydraulic pressure is supplied to the clearance adjustment piston, the clearance adjusting piston strokes to thereby press the pressing piston. Is in contact with the friction plate so that the clearance of the friction plate becomes zero, and when the second hydraulic pressure is supplied to the pressing piston from this state, the pressing piston presses the friction plate so that a fastening state is achieved. The hydraulic control means is configured to control the hydraulic pressure for fastening the third friction element, and at the same time, the idle stop means During automatic gin stop, in addition to supplying the standby hydraulic pressure to the first friction element, the first hydraulic pressure is supplied to the clearance adjustment piston, and the engine is based on a select operation from the non-traveling range to the forward traveling range. At the time of restart, in addition to increasing the hydraulic pressure supplied to the first friction element up to the fastening hydraulic pressure, the second hydraulic pressure is supplied to the pressing piston, and a select operation from the non-traveling range to the reverse traveling range is performed. When the engine is restarted based on the above, in addition to the discharge of the standby hydraulic pressure from the first friction element and the supply of the fastening hydraulic pressure to the second friction element, the second hydraulic pressure is supplied to the pressing piston. Is preferred.

  According to this configuration, when the range is selected to the forward travel range while the engine is automatically stopped in the non-travel range, the second hydraulic pressure is further supplied to the pressing piston of the third friction element. At this time, during the automatic engine stop, the first hydraulic pressure is supplied to the clearance adjusting piston of the third friction element, so that the pressing piston has a short time from the position where the friction plate clearance is zero (zero clearance position). Press the friction plate inside. Therefore, the third friction element is quickly brought into the engaged state, and the engagement delay of the third friction element at the time of engine restart, the engagement shock, and the like are suppressed.

  On the other hand, when the range is selected to the reverse travel range while the engine is automatically stopped in the non-travel range, similarly, the second hydraulic pressure is supplied to the press piston of the third friction element, and the press piston is at the zero clearance position. The friction plate is pressed within a short time. Therefore, the third friction element is quickly brought into the engaged state, and the switching response to the reverse start stage is ensured.

  In the present invention, the hydraulic pressure control means discharges the standby hydraulic pressure from the first friction element and supplies the pressure to the pressing piston when the engine is restarted based on a selection operation from the non-travel range to the reverse travel range. It is preferable to supply the second hydraulic pressure at the same time.

  According to this configuration, compared with the case where the discharge of the standby hydraulic pressure from the first friction element and the supply of the second hydraulic pressure to the pressing piston are sequentially performed, the switching to the reverse start stage is further performed. Promptly.

  In the present invention, the first friction element and the second friction element include a return spring that biases the pistons of the first friction element and the second friction element toward the release side, and the hydraulic control means includes a non-traveling range. When the engine is restarted based on the selection operation from the forward travel range to the forward travel range, the second hydraulic pressure is supplied to the pressing piston, and then the hydraulic pressure for the first friction element is increased to the fastening hydraulic pressure, and the engine is moved backward from the non-travel range. When restarting the engine based on the selection operation to the travel range, it is preferable that the second hydraulic pressure is supplied to the pressing piston and then the fastening hydraulic pressure is supplied to the second friction element.

  According to this configuration, even if the first friction element and the second friction element are provided with return springs, the engagement delay or the engagement shock of the first friction element at the time of the selection operation from the non-traveling range to the forward traveling range is prevented. This suppresses the switching responsiveness to the reverse start stage during the selection operation from the non-travel range to the reverse travel range. That is, a relatively high hydraulic pressure is required to stroke the pistons of the first friction element and the second friction element to the fastening side against the urging force of the return spring. On the other hand, immediately after the engine is restarted, the hydraulic pressure generated by the mechanical oil pump driven by the engine is still low. Therefore, in this configuration, when the engine is restarted, the second hydraulic pressure is first supplied to the pressing piston, and then the first hydraulic element is fastened to the first friction element or the second friction element after the generated hydraulic pressure of the mechanical oil pump becomes high. By supplying hydraulic pressure, even if a return spring is provided, the first friction element or the second friction element is quickly brought into an engaged state.

  The present invention suppresses the frictional element engagement delay and engagement shock when the N → D select operation is performed while the engine is automatically stopped in the N range, and the reverse start when the N → R select operation is performed. Since the control device for an automatic transmission capable of both ensuring the responsiveness to switching to a stage is provided, it can be preferably applied to an automatic transmission mounted on an idle stop vehicle.

1 is a skeleton diagram of an automatic transmission according to an embodiment of the present invention. It is a fastening table | surface of the said automatic transmission. It is sectional drawing of the low reverse brake with which the said automatic transmission was equipped, and the state which supplied the hydraulic pressure to both A chamber and B chamber is shown. Similarly, the state where the hydraulic pressure is supplied only to the B chamber is shown. Similarly, the state in which the hydraulic pressure is discharged from both the A chamber and the B chamber is shown. It is a figure which shows the principal part of the hydraulic circuit with which the said automatic transmission was equipped. It is a control system figure of a vehicle provided with the above-mentioned automatic transmission. It is a time chart which shows an example of control operation in case the range of the said automatic transmission is switched from D-> N-> D. It is a time chart which shows an example of control operation in case the range of the said automatic transmission is switched from D-> N-> R. 10 is a flowchart of the control operation of FIGS. 8 and 9.

(1) Configuration FIG. 1 is a skeleton diagram of an automatic transmission 1 according to this embodiment. The automatic transmission 1 automatically stops an engine (not shown) when a predetermined stop condition is satisfied, and performs a vehicle (idle stop) in which idle stop control is performed to restart the engine when a predetermined restart condition is satisfied in the engine automatic stop state. It is mounted on a stop vehicle.

  Examples of the stop condition include, for example, a basic condition that the brake pedal is depressed while the vehicle speed is substantially zero, and an additional condition that the remaining capacity of the battery is a predetermined amount or more. The difference between the set temperature of the air conditioner and the temperature in the passenger compartment is not more than a predetermined value. As the restart condition, for example, in the D range (forward travel range), the brake pedal is no longer depressed, and the non-travel range such as the N range (neutral range) and the P range (parking range). For example, the N → D select operation or the P → D select operation is performed, or the N → R select operation or the P → R select operation is performed.

  The automatic transmission 1 has an input shaft 2 to which engine output torque is input via a torque converter (not shown). First, second, and third planetary gear sets (hereinafter, “planetary gear sets” are simply referred to as “gear sets”) 10, 20, and 30 are arranged on the input shaft 2 from the engine side (right side in the figure). As friction elements for switching the power transmission path formed by these gear sets 10, 20, and 30, a low clutch (corresponding to the “first friction element” of the present invention) 40, a high clutch 50, a low reverse brake (LR) Brake) (corresponding to the “third friction element” of the present invention) 60, 2-speed / 6-speed brake (26 brake) 70, and reverse speed / 3-speed / 5-speed brake (R35 brake) 80) corresponding to “two friction elements”. These friction elements 40, 50, 60, 70, 80 are hydraulic. The low clutch 40 and the high clutch 50 selectively transmit the power from the input shaft 2 to the gear sets 10, 20, 30. The LR brake 60, the 26 brake 70, and the R35 brake 80 fix predetermined rotating elements of the gear sets 10, 20, and 30 to the transmission case 3.

  The gear sets 10, 20, 30 are all sun gears 11, 21, 31, pinions 12, 22, 32 that mesh with the sun gears 11, 21, 31, and carriers 13, 23, 33 that support the pinions 12, 22, 32. And ring gears 14, 24, 34 that mesh with the pinions 12, 22, 32.

  The sun gear 11 of the first gear set 10 and the sun gear 21 of the second gear set 20 are coupled and connected to the output member 41 of the low clutch 40. The carrier 23 of the second gear set 20 is connected to the output member 51 of the high clutch 50. A sun gear 31 of the third gear set 30 is connected to the input shaft 2. The output gear 4 is connected to the carrier 13 of the first gear set 10. The output gear 4 outputs the output torque of the automatic transmission 1 to the drive wheel side not shown.

  The ring gear 14 of the first gear set 10 and the carrier 23 of the second gear set 20 are coupled, and an LR brake 60 is interposed between these and the transmission case 3. The ring gear 24 of the second gear set 20 and the carrier 33 of the third gear set 30 are coupled, and a 26 brake 70 is interposed between the ring gear 24 and the transmission case 3. An R35 brake 80 is interposed between the ring gear 34 of the third gear set 30 and the transmission case 3.

  With the above configuration, the automatic transmission 1 has a forward 1st to 6th speed in the D range, as shown in FIG. 2, by a combination of the engagement states of the five friction elements 40, 50, 60, 70, and 80. Reverse speed in the R range (reverse running range) is achieved. As is apparent from FIG. 2, in this embodiment, the low clutch 40 and the LR brake 60 are engaged at the first forward speed (forward start stage), and the LR brake 60 and the R35 brake 80 are set at the reverse speed (reverse start stage). Is concluded. That is, the low clutch 40 is engaged at the start stage of the D range and released at the start stage of the R range. The R35 brake 80 is released at the start stage of the D range and is engaged at the start stage of the R range. The LR brake 60 is engaged at both the D range start stage and the R range start stage.

  As shown in FIGS. 3 to 5, the LR brake 60 is a double-acting friction element having a clearance adjusting function for improving controllability. The LR brake 60 includes a clearance adjusting piston (B piston) 62 and a pressing piston (A piston) 63. The B piston 62 is divided into a first piston member 62a and a second piston member 62b in order to improve the assemblability. After the assembly, the B piston 62 is integrated by a disc spring 60a, a snap ring 60b, and an annular fixing plate 60c. Yes.

  The B piston 62 is fitted in a cylinder 3a formed in the transmission case 3 so as to be capable of stroke in the axial direction. A hydraulic chamber (B chamber) 64 for the B piston 62 is formed between the B piston 62 and the transmission case 3. The B chamber 64 is supplied with hydraulic pressure (B chamber pressure) via a B chamber line 118 (see FIG. 6) formed in the transmission case 3.

  The A piston 63 is fitted inside the B piston 62 so as to be relatively movable in the axial direction. A hydraulic chamber (A chamber) 65 of the A piston 63 is formed between the A piston 63 and the B piston 62. The A chamber 65 is supplied with hydraulic pressure (A chamber pressure) via an A chamber line 119 (see FIG. 6) formed in the transmission case 3 and a communication hole 62c formed in the second piston member 62b.

  When a predetermined first hydraulic pressure (for example, several hundred kPa) is supplied to the B chamber 64 and a predetermined second hydraulic pressure (for example, several hundred kPa) is supplied to the A chamber 65, the hydraulic pressure is supplied to the colored portion in FIG. As shown in FIG. 4, the B piston 62 strokes to the left side of the drawing until it abuts against the stopper 67 against the urging force of the return spring 66 by the first hydraulic pressure, and the A piston 63. Further, the transmission case 3 and the braked member (that is, the member in which the ring gear 14 of the first gear set 10 and the carrier 23 of the second gear set 20 are coupled) are stroked to the left side of the drawing and are pressed by the second hydraulic pressure. The plurality of friction plates 68 that are alternately engaged with each other are pressed. Thereby, LR brake 60 will be in an engagement state.

  When the hydraulic pressure of the A chamber 65 (A chamber pressure) is discharged from this state, the pressing force of the A piston 63 is released while the A piston 63 is in contact with the friction plate 68 as shown in FIG. As a result, the LR brake 60 is released. At this time, the clearance of the friction plate 68 is zero, and the A piston 63 stands by at the zero clearance position.

  Further, when the hydraulic pressure in the B chamber 64 (B chamber pressure) is discharged from this state, the B piston 62 strokes to the right side of the drawing by the urging force of the return spring 66 as shown in FIG. At this time, due to the frictional force of the sealing member attached to the A piston 63, the A piston 63 moves to the right in the drawing together with the B piston 62 while maintaining the positional relationship with the B piston 62.

  Next time, when the LR brake 60 is engaged, first, hydraulic pressure is supplied to the B chamber 64. As a result, the A piston 63 and the B piston 62 make a stroke to the left in the figure while maintaining the positional relationship (see FIG. 4). At this time, the A piston 63 contacts the friction plate 68 and the clearance of the friction plate 68 becomes zero. That is, the A piston 63 enters a standby state at the zero clearance position. When the hydraulic pressure is supplied to the A chamber 65 from this state, the A piston 63 presses the friction plate 68 substantially simultaneously with the supply of the hydraulic pressure, and the LR brake 60 is fastened with good responsiveness (see FIG. 3).

  In short, when the LR brake 60 is engaged, the hydraulic pressure is supplied in the order of the B chamber 64 → A chamber 65, and when released, the hydraulic pressure is discharged in the order of the A chamber 65 → B chamber 64.

  As is apparent from FIGS. 3 to 5, the LR brake 60 includes a return spring 66 that biases the B piston 62 toward the release side, but includes a return spring that biases the A piston 63 toward the release side. Absent. Further, although not shown, the low clutch 40 that is engaged with the LR brake 60 at the first forward speed and the R35 brake 80 that is engaged with the LR brake 60 at the reverse speed are both not shown, but both have a single piston and a single hydraulic pressure. A return spring having a chamber and biasing the piston toward the release side is provided.

  FIG. 6 is a diagram showing a main part of the hydraulic circuit 100 provided in the automatic transmission 1. That is, the automatic transmission 1 includes a hydraulic circuit 100 for selectively supplying hydraulic pressure to the friction elements 40, 50, 60, 70, and 80 to achieve the respective shift stages shown in FIG. As described above, since the vehicle according to the present embodiment is an idle stop vehicle, in addition to the mechanical oil pump 102 that is driven by the engine to generate hydraulic pressure, the motor 101a is used during automatic engine stop by idle stop control. An electric oil pump 101 that is driven to generate hydraulic pressure is provided.

  Hydraulic pressure can be introduced into the hydraulic circuit 100 from both the mechanical oil pump 102 and the electric oil pump 101. The hydraulic circuit 100 includes a low clutch 40 (more specifically, its hydraulic chamber) that is engaged with the introduced hydraulic pressure at the first forward speed, an R35 brake 80 (more specifically, its hydraulic chamber) that is engaged at the reverse speed, and forward. As a valve for supplying to the LR brake 60 (more specifically, the B chamber 64 and the A chamber 65) fastened at the first speed and the reverse speed, the pump switching valve 103, the manual valve 104, the first linear solenoid valve (the first linear solenoid valve) 1LSV) 105, a second linear solenoid valve (second LSV) 106, a low reverse shift valve (LR shift valve) 107, an on / off solenoid valve (on / off SV) 108, and a third linear solenoid valve (third LSV) 109. Yes.

  The pump switching valve 103 switches which hydraulic pressure of the two pumps 101 and 102 is supplied to the two friction elements 40 and 60. The manual valve 104 is linked to the driver's range selection operation. The first LSV 105 controls the hydraulic pressure (low clutch pressure) supplied to the hydraulic chamber of the low clutch 40. The second LSV 106 controls the hydraulic pressure (A chamber pressure) supplied to the A chamber 65 of the LR brake 60. The LR shift valve 107 and the on / off SV 108 are arranged so that the hydraulic pressure supply / discharge sequence with respect to the B chamber 64 and the A chamber 65 of the LR brake 60 is determined when the LR brake 60 is fastened, as described above. When the hydraulic pressure is supplied and released, the hydraulic pressure is regulated so that the hydraulic pressure is discharged in the order of the A chamber 65 → the B chamber 64. The third LSV 109 controls the hydraulic pressure (R35 brake pressure) supplied to the hydraulic chamber of the R35 brake 80.

  The pump switching valve 103 has ports a and b for switching the position of the spool 103a at both ends in the axial direction. When the electric oil pump 101 is driven, the hydraulic pressure of the electric oil pump 101 is introduced into the port a on the left side of the figure, and the spool 103a is shifted to the right side as shown. When the mechanical oil pump 102 is driven, the hydraulic pressure of the mechanical oil pump 102 is introduced into the port b on the right side of the figure, and the spool 103a is shifted to the left side.

  The pump switching valve 103 further has input ports c and d and an output port e for the low clutch 40, and input ports f and g and an output port h for the LR brake 60. When the spool 103a is shifted to the right side, the port c and the port e for the low clutch 40 communicate with each other, and the port f and the port h for the LR brake 60 communicate with each other as illustrated. When the spool 103a is shifted to the left, the port d and the port e for the low clutch 40 communicate with each other, and the port g and the port h for the LR brake 60 communicate with each other.

  Oil paths 111 and 112 led from the electric oil pump 101 are connected to the input port c for the low clutch 40 and the input port f for the LR brake 60, respectively. Oil passages 113 and 114 led from the mechanical oil pump 102 are connected to the input port d for the low clutch 40 and the input port g for the LR brake 60, respectively. However, the oil passage 113 is guided from the mechanical oil pump 102 via the manual valve 104. The manual valve 104 communicates the mechanical oil pump 102 with the oil passage 113 when the D range and the R range are selected, and drains the oil passage 113 when the N range and the P range are selected. Let

  The low clutch line 115 led from the hydraulic chamber of the low clutch 40 is connected to the output port e for the low clutch 40 via the first LSV 105. The R35 brake line 120 led from the hydraulic chamber of the R35 brake 80 is connected to the pump switching valve 103 side of the low clutch line 115 from the first LSV 105 via the third LSV 109. An LR brake line 116 led from the LR shift valve 107 is connected to the output port h for the LR brake 60. A B chamber line 118 led from the B chamber 64 of the LR brake 60 is connected to the LR shift valve 107. The A chamber line 119 led from the A chamber 65 of the LR brake 60 is connected to the B chamber line 118 via the second LSV 106.

  The first LSV 105, the second LSV 106, and the third LSV 109 all have an input port i, an output port j, and a drain port k. The input port i and the output port j are communicated when opened, and the output port j is communicated when closed. Communicate with drain port k.

  An oil passage 117 led from the mechanical oil pump 102 is connected to one end of the LR shift valve 107 in the axial direction via an on / off SV 108. The on-off SV 108 introduces the hydraulic pressure of the mechanical oil pump 102 to one end of the LR shift valve 107 when it is opened, shifts the spool (not shown) of the LR shift valve 107 to the right side, and the B chamber line 118 and the A chamber line. Drain 119. On the other hand, when the valve is closed, the spool is shifted to the left, and the LR brake line 116 is communicated with the B chamber line 118 and the A chamber line 119.

  As described above, the LR brake 60 is engaged only at the first forward speed and the reverse speed with relatively low use frequency and use time. For this reason, the ON / OFF SV 108 has an open state in which the B chamber line 118 and the A chamber line 119 are drained longer than a closed state in which the LR brake line 116 and the B chamber line 118 and the A chamber line 119 are communicated. . Therefore, in the present embodiment, the normally open type on / off SV 108 that is open when not energized (OFF) is employed. As a result, the power consumption of the on / off SV 108 can be reduced, and the fuel efficiency is improved.

  FIG. 7 is a control system diagram of an idle stop vehicle provided with the automatic transmission 1. The control device 200 is a microprocessor including a CPU, a ROM, a RAM, and the like, and corresponds to the “idle stop unit” and the “hydraulic control unit” of the present invention.

  The control device 200 receives the signal from the range sensor 201 that detects the range of the automatic transmission 1 selected by the driver, the signal from the vehicle speed sensor 202 that detects the vehicle speed of the vehicle, and the amount of operation of the driver's accelerator pedal. A signal from the accelerator operation amount sensor 203 to be detected, a signal from the brake switch 204 to detect the depression of the brake pedal of the driver, a signal from the engine speed sensor 205 to detect the engine speed, and the electric oil pump 101 A signal is input from an electric oil pump rotation speed sensor 206 that detects the rotation speed.

  Based on these signals, the control device 200 outputs control signals to the engine fuel supply device 211, the ignition device 212, and the starter 213 in order to perform idle stop control. In addition, in order to perform hydraulic control of the low clutch 40, the LR brake 60, and the R35 brake 80 of the automatic transmission 1 during the idle stop control, a control signal is output to the electric oil pump motor 101a and the automatic transmission 1 Control signals are output to the first LSV 105, the second LSV 106, the third LSV 109, and the on / off SV 108 of the hydraulic circuit 100.

  FIG. 8 is a time chart illustrating an example of a control operation performed by the control device 200. This time chart shows changes in various signals and state quantities from before the vehicle stops until after starting. The control device 200 performs idle stop control and hydraulic control of the low clutch 40 and the LR brake 60 while the vehicle is stopped. In the example of FIG. 8, during the idle stop control, the range of the automatic transmission 1 is switched from the D range to the N range, and then the engine is restarted by performing the N → D selection operation (N → D select restart).

  In FIG. 8, time t1 is a time when the idle stop state flag is changed from 0 to 1, time t2 is a time when the flag is changed from 1 to 2, time t3 is a time when the flag is changed from 2 to 3, and time t4 is A The time when the chamber pressure reaches the second hydraulic pressure and the low clutch pressure starts to be increased, and the time t5 is the time when the vehicle starts.

  Until time t1, the vehicle is traveling forward in the D range. The forward speed of the shift stage of the automatic transmission 1 is achieved. That is, the hydraulic pressure (engaged hydraulic pressure) for engaging the low clutch 40 is supplied to the hydraulic chamber of the low clutch 40, the first hydraulic pressure is supplied to the B chamber 64 of the LR brake 60, and the first hydraulic pressure is supplied to the A chamber 65. Two hydraulic pressures are supplied, and both the low clutch 40 and the LR brake 60 are engaged. The hydraulic pressure is not supplied to the R35 brake 80 that is engaged at the reverse speed because the third LSV 109 is in the closed state.

  Since the mechanical oil pump (OP) 102 is driven by the engine to generate hydraulic pressure, and the electric oil pump (OP) 101 does not generate hydraulic pressure by turning off the motor 101a, the spool 103a of the pump switching valve 103 is shown in FIG. To the left side (denoted as “mechanical OP side” in FIG. 8), and the hydraulic pressure generated by the mechanical pump 102 is transferred to the low clutch via the oil passages 113, 114, the low clutch line 115 and the LR brake line 116. 40 and LR brake 60 are supplied.

  Although not shown, the on / off SV 108 is ON (energized). As a result, the normally open type on / off SV 108 is closed, the spool of the LR shift valve 107 is shifted to the left in FIG. 6, and the LR brake line 116, the B chamber line 118, and the A chamber line 119 communicate with each other. The on / off SV 108 is turned off (non-energized) at gear speeds other than the first forward speed and the reverse speed at which the LR brake 60 is engaged.

  In this state, as the accelerator operation amount decreases, the vehicle speed, the engine speed, and the turbine speed (not shown) (the output speed of the torque converter, which is the same as the speed of the input shaft 2 of the automatic transmission 1) decrease. Then, when the brake pedal is depressed and the vehicle stops, for example, waiting for an intersection signal (vehicle speed and turbine speed = 0), the idle stop state flag changes from 0 to 1 (time t1). At this time, among the stop conditions of the idle stop control, the basic condition that the brake pedal is depressed with the vehicle speed being substantially zero is satisfied.

  When the basic condition is satisfied, the control device 200 turns on the motor 101a and starts driving the electric oil pump 101. As a result, the electric oil pump 101 is driven by the motor 101a to generate hydraulic pressure. The generated hydraulic pressure is guided to the pump switching valve 103, the spool 103 a is shifted to the right side of FIG. 6 (denoted as “electric OP side” in FIG. 8), and the hydraulic pressure generated by the electric oil pump 101 is oil paths 111, 112. Are supplied to the low clutch 40 and the LR brake 60 via the low clutch line 115 and the LR brake line 116. At this time, the low oil pressure of the electric oil pump 101 is supplied to the low clutch 40 and the LR brake 60, which was previously supplied with the hydraulic pressure of the mechanical oil pump 102.

  Next, among the stop conditions for the idle stop control, the control device 200 adds that the remaining capacity of the battery is a predetermined amount or more, and that the difference between the set temperature of the air conditioner and the temperature in the passenger compartment is equal to or less than a predetermined value It is determined whether or not the target condition is satisfied, in other words, whether or not the engine can be stopped. As a result, when the additional condition is satisfied, the idle stop state flag changes from 1 to 2 (time t2). With this, the control device 200 automatically stops the engine. As the engine stops, the mechanical oil pump 102 stops generating the hydraulic pressure, but as described above, the hydraulic pressure of the electric oil pump 101 is already supplied to the low clutch 40 and the LR brake 60 at this time. There is no.

  The control device 200 controls the first LSV 105 together with the automatic engine stop to reduce the low clutch pressure from the engagement hydraulic pressure to the standby hydraulic pressure Pd in the D range. In the present embodiment, the standby hydraulic pressure Pd is a hydraulic pressure that is lower than the fastening hydraulic pressure by a predetermined amount, but may be the same hydraulic pressure as the fastening hydraulic pressure.

  In addition, the control device 200 controls the second LSV 106 together with the automatic engine stop to lower the A chamber pressure of the LR brake 60 from the second hydraulic pressure to the third hydraulic pressure. The third hydraulic pressure is lower than the second hydraulic pressure (for example, several tens of kPa). Therefore, the A piston 63 stops pressing the friction plate 68 and the LR brake 60 is released. As a result, the first forward speed is not achieved, and the power transmission path of the automatic transmission 1 is interrupted. In FIG. 8, the symbol “α” indicates a period during which the power transmission path of the automatic transmission 1 is interrupted (non-achievement period of the first forward speed). By setting the A chamber pressure to a low pressure state, the electric oil consumption of the electric oil pump 101 can be reduced, and the fuel consumption performance is improved.

  If necessary, the control device 200 supplies the standby hydraulic pressure Pd equal to or lower than the engagement hydraulic pressure to the hydraulic chamber of the low clutch 40 during automatic engine stop, supplies the first hydraulic pressure to the B chamber 64 of the LR brake 60, and the LR brake. A third hydraulic pressure lower than the second hydraulic pressure is supplied to the A chamber 65 of 60. The third hydraulic pressure is a hydraulic pressure that puts the LR brake 60 in a released state, but is a hydraulic pressure that can hold the zero clearance position of the A piston 63 in the released LR brake 60. Such a value of the third hydraulic pressure is experimentally obtained in advance.

  Next, the control device 200 determines whether or not the range of the automatic transmission 1 has been switched from the D range to the N range. As a result, when the D → N selection operation is performed, the first LSV 105 is controlled to reduce the low clutch pressure from the standby hydraulic pressure Pd in the D range to the standby hydraulic pressure Pn in the N range. The standby hydraulic pressure Pn in the N range is lower than the standby hydraulic pressure Pd in the D range by a predetermined amount.

  Next, the control device 200 determines whether or not the restart condition in the N range that the N → D selection operation has been performed among the restart conditions of the idle stop control is satisfied, in other words, the driver has started. It is determined whether or not the intention is shown. As a result, when the restart condition is satisfied, the idle stop state flag changes from 2 to 3 (time t3). With this, the control device 200 restarts the engine (N → D select restart).

  As the engine restarts, the mechanical oil pump 102 is driven by the engine to resume the generation of hydraulic pressure. The control device 200 stops the driving of the electric oil pump 101 by turning off the motor 101a simultaneously with the restart of the engine, that is, simultaneously with the restart of the hydraulic pressure generation of the mechanical oil pump 102. As a result, the spool 103a of the pump switching valve 103 is again shifted to the mechanical OP side, and the hydraulic pressure of the mechanical oil pump 102 is supplied to the low clutch 40 and the LR brake 60.

  The control device 200 controls the second LSV 106 and restarts the engine to increase the A chamber pressure of the LR brake 60 from the third hydraulic pressure toward the second hydraulic pressure, as indicated by reference numeral A in FIG. As a result, the A piston 63 presses the friction plate 68 substantially simultaneously with the supply of the hydraulic pressure, and the LR brake 60 enters the engaged state with good responsiveness. At this time, since it is immediately after the engine is restarted, the hydraulic pressure generated by the mechanical oil pump 102 driven by the engine is still low. However, since the LR brake 60 is not provided with the return spring that biases the A piston 63 to the release side as described above, the A piston 63 is sufficient even if the generated hydraulic pressure of the mechanical oil pump 102 is low. The friction plate 68 is pressed well, and the LR brake 60 is quickly engaged. In addition, since the drive of the electric oil pump 101 can be stopped at an early stage (because the drive time is short), the power consumption of the motor 101a can be reduced, and the fuel efficiency is improved.

  When the A chamber pressure of the LR brake 60 reaches the second hydraulic pressure, the control device 200 controls the first LSV 105 to change the low clutch pressure from the standby hydraulic pressure Pn when the low clutch pressure is in the N range, as indicated by reference character A in FIG. The pressure is increased toward the fastening hydraulic pressure (time t4). Thereby, the low clutch 40 will be in a fastening state. Therefore, since the LR brake 60 has been fastened first, the first forward speed is achieved, and the power transmission path of the automatic transmission 1 that has been shut off is formed again as indicated by the symbol α. At this time, since a certain amount of time has elapsed since the engine restart, the generated hydraulic pressure of the mechanical oil pump 102 is sufficiently high. Therefore, as described above, even if the low clutch 40 is provided with a return spring that urges the piston toward the release side, the piston of the low clutch 40 strokes toward the engagement side sufficiently satisfactorily, and the low clutch 40 quickly moves. It will be in a fastening state.

  Since the brake pedal is still depressed at this point, the vehicle speed does not rise even if the power transmission path is re-formed. The driver stops depressing the brake pedal, and the vehicle speed increases simultaneously with the start of the vehicle that depresses the accelerator pedal (time t5).

  FIG. 9 is a time chart illustrating another example of the control operation performed by the control device 200. The control device 200 performs idle stop control and hydraulic control of the low clutch 40, the LR brake 60, and the R35 brake 80 while the vehicle is stopped. In the example of FIG. 9, during the idle stop control, the range of the automatic transmission 1 is switched from the D range to the N range, and then the engine is restarted by performing the N → R select operation (N → R select restart).

  In FIG. 9, a time t1 ′ is a time when the idle stop state flag changes from 0 to 1, a time t2 ′ is a time when the flag changes from 1 to 2, a time t3 ′ is a time when the flag changes from 2 to 3, and a time t4 'Is the time when the A chamber pressure reaches the second hydraulic pressure and the R35 brake pressure starts to be increased, and time t5' is the time when the vehicle starts. Compared with FIG. 8, since the time t3 ′ and later are different, only the description after the time t3 ′ will be described.

  That is, the control device 200 reduces the low clutch pressure to the standby hydraulic pressure Pn in the N range due to the D → N selection operation during the automatic engine stop, and then restarts the idle stop control. It is determined whether or not the restart condition in the N range that the N → R selection operation has been performed is satisfied, in other words, whether or not the driver has indicated an intention to start (reverse start). As a result, when the restart condition is satisfied, the idle stop state flag changes from 2 to 3 (time t3 '). With this, the control device 200 restarts the engine (N → R select restart).

  As the engine restarts, the mechanical oil pump 102 is driven by the engine to resume the generation of hydraulic pressure. The control device 200 stops the driving of the electric oil pump 101 by turning off the motor 101a simultaneously with the restart of the engine, that is, simultaneously with the restart of the hydraulic pressure generation of the mechanical oil pump 102. As a result, the spool 103a of the pump switching valve 103 is again shifted to the mechanical OP side, and the hydraulic pressure of the mechanical oil pump 102 is supplied to the low clutch 40 and the LR brake 60.

  The control device 200 controls the first LSV 105 together with the engine restart to discharge the low clutch pressure, that is, the standby hydraulic pressure Pn at the N range. As a result, the low clutch 40 is released. At the same time as the discharge of the low clutch pressure, the control device 200 controls the second LSV 106 so that the A chamber pressure of the LR brake 60 is changed from the third hydraulic pressure to the second hydraulic pressure, as indicated by reference numeral in FIG. Increase the pressure. As a result, the A piston 63 presses the friction plate 68 substantially simultaneously with the supply of the hydraulic pressure, and the LR brake 60 enters the engaged state with good responsiveness. At this time, since it is immediately after the engine is restarted, the hydraulic pressure generated by the mechanical oil pump 102 driven by the engine is still low. However, since the LR brake 60 is not provided with the return spring that biases the A piston 63 to the release side as described above, the A piston 63 is sufficient even if the generated hydraulic pressure of the mechanical oil pump 102 is low. The friction plate 68 is pressed well, and the LR brake 60 is quickly engaged. In addition, since the drive of the electric oil pump 101 can be stopped at an early stage (because the drive time is short), the power consumption of the motor 101a can be reduced, and the fuel efficiency is improved.

  When the A chamber pressure of the LR brake 60 reaches the second hydraulic pressure, the control device 200 controls the third LSV 109 so that the R35 brake 80 is engaged in the hydraulic chamber of the R35 brake 80 as indicated by reference numeral in FIG. Is supplied (time t4 ′). In other words, the R35 brake pressure is increased toward the engagement hydraulic pressure. Thereby, R35 brake 80 will be in a fastening state. Therefore, since the LR brake 60 has been fastened first, the reverse speed is achieved, and the power transmission path of the automatic transmission 1 that has been shut off is formed again, as indicated by the symbol α. At this time, since a certain amount of time has elapsed since the engine restart, the generated hydraulic pressure of the mechanical oil pump 102 is sufficiently high. Therefore, as described above, even if the R35 brake 80 is provided with a return spring that urges the piston toward the release side, the piston of the R35 brake 80 strokes to the engagement side sufficiently well, so that the R35 brake 80 quickly It will be in a fastening state.

  Since the brake pedal is still depressed at this point, the vehicle speed does not rise even if the power transmission path is re-formed. The driver stops depressing the brake pedal, and the vehicle speed increases at the same time as the vehicle depressing the accelerator pedal (starting backward) (time t5 ').

  FIG. 10 is a flowchart showing the control operation of FIG. 8 and FIG. 9 performed by the control device 200. However, only the main characteristic processing is extracted and shown.

  In step S1, the control device 200 determines whether or not the idle stop state flag has changed from 1 to 2. If YES (time t2, t2 ′ in FIGS. 8 and 9), the engine 200 in step S2 After that, when the engine speed falls below a predetermined threshold, the low clutch pressure is lowered from the engagement hydraulic pressure to the standby hydraulic pressure (denoted as “D hydraulic pressure” in FIG. 10) Pd in the D range. The A chamber pressure of the LR brake 60 is decreased from the second hydraulic pressure to the third hydraulic pressure.

  Next, in step S3, control device 200 determines whether or not the range of automatic transmission 1 has been switched from the D range to the N range. If YES, step S4 determines that the low clutch pressure is in the D range. The standby hydraulic pressure Pd is reduced to the standby hydraulic pressure (indicated as “N hydraulic pressure” in FIG. 10) Pn in the N range.

  Next, in step S5, the control device 200 determines whether or not the idle stop state flag has changed from 2 to 3, and if YES (time t3, t3 ′ in FIGS. 8 and 9), in step S6. Restart the engine.

  Next, in step S7, the control device 200 determines whether the change of the idle stop state flag from 2 to 3 is due to the range N → D selection operation being performed or the N → R selection operation being performed. When the N → D select operation is performed (in the case of FIG. 8), the process proceeds to step S8. When the N → R select operation is performed (in the case of FIG. 9), the process proceeds to step S10.

  In step S8, the control device 200 increases the A chamber pressure of the LR brake 60 toward the second hydraulic pressure (reference number A in FIG. 8).

  Next, in step S9, the control device 200 increases the low clutch pressure from the standby hydraulic pressure Pn when the LR brake 60 is in the N range to the engagement hydraulic pressure after the A chamber pressure is increased to the second hydraulic pressure (FIG. 8). Sign a).

  On the other hand, in step S10, the control device 200 discharges the low clutch pressure (standby hydraulic pressure Pn in the N range) and simultaneously increases the A chamber pressure of the LR brake 60 toward the second hydraulic pressure (reference numeral in FIG. 9). F).

  Next, in step S11, the control device 200 increases the R35 brake pressure toward the engagement hydraulic pressure after the A chamber pressure of the LR brake 60 is increased to the second hydraulic pressure (reference sign in FIG. 9).

(2) Operation, etc. As described above in detail with reference to the drawings, the control device for the automatic transmission 1 according to the present embodiment automatically stops the engine when a predetermined stop condition is satisfied, It is mounted on a vehicle (idle stop vehicle) having a control device 200 that performs idle stop control for restarting the engine when the restart condition is satisfied. The automatic transmission 1 includes a low clutch 40 that is engaged at the first forward speed and released at the reverse speed, and an R35 brake 80 that is released at the first forward speed and is engaged at the reverse speed. Then, the hydraulic pressure for engaging the low clutch 40 and the R35 brake 80 is controlled (FIGS. 6 and 7).

  While the engine is automatically stopped by the idle stop control, the control device 200 supplies the low clutch 40 with standby hydraulic pressures Pd and Pn that are equal to or lower than the engagement hydraulic pressure at which the low clutch 40 is engaged, and from the N range to the D range. When the engine is restarted based on the selection operation, the hydraulic pressure supplied to the low clutch 40 is increased from the standby hydraulic pressure Pn in the N range to the engagement hydraulic pressure (symbol A in FIG. 8), and the N range to the R range is increased. When the engine is restarted based on the select operation, the standby hydraulic pressure Pn is discharged from the low clutch 40, and the fastening hydraulic pressure for engaging the R35 brake 80 is supplied to the R35 brake 80 (reference numeral in FIG. 9). It is.

  In addition, the standby hydraulic pressures Pd and Pn are set to lower values when the range of the automatic transmission 1 is the N range (Pn) than when the range is the D range (Pd) (N range). Standby hydraulic pressure Pn <D range when standby hydraulic pressure Pd).

  According to this configuration, when the range is selected to the D range while the engine is automatically stopped in the N range (time t3 in FIG. 8), the engine is restarted and the hydraulic pressure supplied to the low clutch 40 is increased. The low pressure is increased from the standby hydraulic pressure Pn to the engagement hydraulic pressure, and the low clutch 40 is engaged. At this time, since the standby hydraulic pressure Pn at the time of the N range is supplied to the low clutch 40 during the automatic engine stop, the low clutch 40 is compared with a case where such hydraulic pressure is not supplied to the low clutch 40. The supplied hydraulic pressure is increased to the fastening hydraulic pressure in a short time. Therefore, the low clutch 40 is quickly engaged, and the engagement delay or engagement shock of the low clutch 40 when the engine is restarted is suppressed.

  On the other hand, when the range is selected to the R range while the engine is automatically stopped in the N range (time t3 ′ in FIG. 9), the engine is restarted and the standby hydraulic pressure Pn is discharged from the low clutch 40, and R35. The engagement hydraulic pressure is supplied to the brake 80, and the R35 brake 80 is engaged. At this time, the standby hydraulic pressure Pn supplied to the low clutch 40 during the automatic engine stop is lower than the standby hydraulic pressure Pd supplied in the D range (Pn <Pd), so the standby hydraulic pressure Pn from the low clutch 40 is compared. It is discharged within a short time. Therefore, the supply of the engagement hydraulic pressure to the R35 brake 80 is started relatively early, and the R35 brake 80 is quickly engaged, and the response to switching to the reverse speed is ensured.

  On the other hand, as indicated by a chain line (symbol X) in FIG. 9, if the standby hydraulic pressure supplied to the low clutch 40 during the automatic engine stop is the same as the standby hydraulic pressure Pd supplied in the D range. The discharge of the standby hydraulic pressure Pd from the low clutch 40 takes time, the supply of the engagement hydraulic pressure to the R35 brake 80 is delayed, the engagement of the R35 brake 80 is delayed, and the response to switching to the reverse speed is reduced. .

  In the present embodiment, the automatic transmission 1 further includes an LR brake 60 that is engaged at both the first forward speed and the reverse speed. The LR brake 60 includes a friction plate 68, a pressing piston 63 that presses the friction plate 68, and a clearance adjustment piston 62 that supports the pressing piston 63 so as to be relatively movable, and is configured as follows. (FIGS. 3 to 5). When the first hydraulic pressure is supplied to the clearance adjustment piston 62, the clearance adjustment piston 62 strokes. As a result, the pressing piston 63 contacts the friction plate 68 and the clearance of the friction plate 68 becomes zero. When the second hydraulic pressure is supplied to the pressing piston 63 from this state, the pressing piston 63 presses the friction plate 68. As a result, the LR brake 60 is engaged.

  The control device 200 also controls the hydraulic pressure for engaging the LR brake 60 (FIGS. 6 and 7). The control device 200 supplies the first hydraulic pressure to the clearance adjustment piston 62 in addition to the supply of the standby hydraulic pressures Pd and Pn to the low clutch 40 during the automatic engine stop by the idle stop control. When the engine is restarted based on the selection operation from the N range to the D range, the second hydraulic pressure is supplied to the pressing piston 63 in addition to the increase of the hydraulic pressure supplied to the low clutch 40 to the engagement hydraulic pressure. When the engine is restarted based on the selection operation from the N range to the R range, the standby hydraulic pressure Pn is discharged from the low clutch 40 and the engagement hydraulic pressure is supplied to the R35 brake 80. In addition, the second hydraulic pressure is supplied to the pressing piston 63 (reference numeral in FIG. 9).

  According to this configuration, when the range is selected to the D range while the engine is automatically stopped in the N range (time t3 in FIG. 8), the second hydraulic pressure is further supplied to the pressing piston 63 of the LR brake 60. The At this time, since the first hydraulic pressure is supplied to the clearance adjustment piston 62 of the LR brake 60 while the engine is automatically stopped, the pressing piston 63 starts from a position where the clearance of the friction plate 68 is zero (zero clearance position). The friction plate 68 is pressed in time. Therefore, the LR brake 60 is quickly engaged, and the engagement delay, engagement shock, and the like of the LR brake 60 when the engine is restarted are suppressed.

  On the other hand, when the range is selected to the R range while the engine is automatically stopped in the N range (time t3 ′ in FIG. 9), similarly, the second hydraulic pressure is supplied to the pressing piston 63 of the LR brake 60 and pressed. The piston 63 presses the friction plate 68 within a short time from the zero clearance position. Therefore, the LR brake 60 is quickly engaged, and the response to switching to the reverse speed is ensured.

  In the present embodiment, the control device 200 discharges the standby hydraulic pressure Pn from the low clutch 40 and applies it to the pressing piston 63 when the engine is restarted based on a selection operation from the N range to the R range. The second hydraulic pressure is supplied simultaneously (time t3 ′ in FIG. 9, step S10 in FIG. 10).

  According to this configuration, compared with the case where the standby hydraulic pressure Pn is discharged from the low clutch 40 and the second hydraulic pressure is supplied to the pressing piston 63 in order, the switching to the reverse speed is further performed. Promptly.

  In the present embodiment, the low clutch 40 and the R35 brake 80 are provided with a return spring that urges the pistons of the low clutch 40 and the R35 brake 80 to the release side. When the engine restarts based on the selection operation from the N range to the D range, the control device 200 supplies the second hydraulic pressure to the pressing piston 63 (reference numeral A in FIG. 8, step S8 in FIG. 10). The hydraulic pressure for the low clutch 40 is increased to the engagement hydraulic pressure (reference symbol A in FIG. 8, step S9 in FIG. 10), and when the engine is restarted based on the selection operation from the N range to the R range, the pressing piston 63 After supplying the second hydraulic pressure (reference numeral in FIG. 9, step S10 in FIG. 10), the fastening hydraulic pressure is supplied to the R35 brake 80 (reference numeral in FIG. 9, step S11 in FIG. 10).

  According to this configuration, even when the low clutch 40 and the R35 brake 80 are provided with return springs, the delay in engagement of the low clutch 40, the engagement shock, and the like during the selection operation from the N range to the D range are suppressed. The switching response to the reverse speed during the selection operation from the R range to the R range is ensured. That is, a relatively high hydraulic pressure is required to stroke the pistons of the low clutch 40 and the R35 brake 80 toward the fastening side against the urging force of the return spring. On the other hand, immediately after the engine restart, the hydraulic pressure generated by the mechanical oil pump 102 driven by the engine is still low. Therefore, in this configuration, when the engine is restarted, the second hydraulic pressure is first supplied to the pressing piston 63, and thereafter, the generated hydraulic pressure of the mechanical oil pump 102 is increased, and then the low clutch 40 or the R35 brake 80 is engaged. By supplying hydraulic pressure, even if a return spring is provided, the low clutch 40 or the R35 brake 80 is quickly brought into an engaged state.

  In the above embodiment, the first forward speed is achieved by engaging the low clutch 40 and the LR brake 60. Instead, the first forward speed is engaged between the engagement of the low clutch 40 and the one-way clutch. The present invention can also be applied to achieve the above. In that case, the control device 200 performs only the hydraulic control of the low clutch 40 in FIG. Specifically, the control device 200 may increase the low clutch pressure from the standby hydraulic pressure Pn in the N range toward the engagement hydraulic pressure when the engine is restarted.

  The P range is the same as the N range except that the output gear 4 of the automatic transmission 1 is mechanically locked. Therefore, in FIG. 8 and FIG. Also good. That is, the present invention can be applied to P → D select restart, P → R select restart, and the like in addition to the N → D select restart and N → R select restart.

1 Automatic transmission 3 Transmission case 40 Low clutch (first friction element)
60 Low reverse brake (third friction element)
62 Clearance adjustment piston (B piston)
63 Piston for pressing (A piston)
64 B chamber (clearance adjustment piston hydraulic chamber)
65 A chamber (hydraulic chamber of piston for pressing)
68 Friction plate 80 Reverse speed, 3rd speed, 5th speed brake (2nd friction element)
101 Electric oil pump 102 Mechanical oil pump 200 Control device (idle stop means, hydraulic control means)

Claims (4)

A control device for an automatic transmission mounted on a vehicle having idle stop means for automatically stopping the engine when a predetermined stop condition is satisfied and restarting the engine when the predetermined restart condition is satisfied in the engine automatic stop state,
A first friction element that is fastened at a forward start stage of the automatic transmission and released at a reverse start stage;
A second friction element that is released at the forward start stage of the automatic transmission and fastened at the reverse start stage;
Hydraulic control means for controlling the hydraulic pressure for fastening the first friction element and the second friction element;
The hydraulic control means includes
While the engine is automatically stopped by the idle stop means, a predetermined standby hydraulic pressure that is equal to or lower than the engagement hydraulic pressure for engaging the first friction element is supplied to the first friction element,
When restarting the engine based on a select operation from the non-travel range to the forward travel range, the hydraulic pressure supplied to the first friction element is increased from the standby hydraulic pressure to the fastening hydraulic pressure,
When the engine is restarted based on the selection operation from the non-travel range to the reverse travel range, the standby hydraulic pressure is discharged from the first friction element and the second friction element is engaged with the second friction element. Is to supply
The control apparatus for an automatic transmission, wherein the standby hydraulic pressure is set to a lower value when the range of the automatic transmission is a non-traveling range than when the range is a forward traveling range. The control apparatus for an automatic transmission according to claim 1,
A third friction element fastened at both the forward start stage and the reverse start stage of the automatic transmission is provided,
The third friction element is
A friction plate, a pressing piston that presses the friction plate, and a clearance adjustment piston that supports the pressing piston to be relatively movable;
When the first hydraulic pressure is supplied to the clearance adjustment piston, the clearance adjustment piston makes a stroke so that the pressing piston comes into contact with the friction plate, and the clearance of the friction plate becomes zero. From this state, the pressing piston When the second hydraulic pressure is supplied to the pressure piston, the pressing piston presses the friction plate to be in a fastening state,
The hydraulic control means includes
While controlling the hydraulic pressure for fastening the third friction element,
During the engine automatic stop by the idle stop means, in addition to supplying the standby hydraulic pressure to the first friction element, the first hydraulic pressure is supplied to the clearance adjustment piston,
When the engine is restarted based on a selection operation from the non-travel range to the forward travel range, in addition to increasing the hydraulic pressure supplied to the first friction element to the fastening hydraulic pressure, the second hydraulic pressure is applied to the pressing piston. Supply
When the engine is restarted based on a selection operation from the non-travel range to the reverse travel range, in addition to discharging the standby hydraulic pressure from the first friction element and supplying the fastening hydraulic pressure to the second friction element, the pressing A control device for an automatic transmission, characterized in that the second hydraulic pressure is supplied to a piston for a vehicle. The control apparatus for an automatic transmission according to claim 2,
The hydraulic pressure control means discharges the standby hydraulic pressure from the first friction element and the second hydraulic pressure to the pressing piston when the engine is restarted based on a selection operation from the non-travel range to the reverse travel range. A control device for an automatic transmission, wherein the supply is performed simultaneously. The control apparatus for an automatic transmission according to claim 2 or 3,
The first friction element and the second friction element include a return spring that biases the pistons of the first friction element and the second friction element toward the release side,
The hydraulic control means includes
When restarting the engine based on a selection operation from the non-traveling range to the forward traveling range, after supplying the second hydraulic pressure to the pressing piston, the hydraulic pressure for the first friction element is increased to the fastening hydraulic pressure,
When the engine is restarted based on a selection operation from the non-traveling range to the reverse traveling range, the second hydraulic pressure is supplied to the pressing piston, and then the fastening hydraulic pressure is supplied to the second friction element. Control device for automatic transmission.

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