JP2010276174A - Control device for automatic transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a control device for an automatic transmission surely preventing engagement of a friction engaging element not to be engaged at the occurrence of a low voltage failure even with a simple circuit configuration eliminating as much as possible with a selector valve for avoiding engagement of the friction engaging element not to be engaged. <P>SOLUTION: A simultaneous engagement avoiding control means shifts to a forward third gear speed stage during control by a low voltage failure determination control means, and controls first and second clutch apply relay valves 21, 22 and a solenoid valve S1 to avoid simultaneous engagement of clutches C-1 to C-3 during the continuation of a low voltage state until the occurrence of the low voltage failure is determined. Consequently, even with the simple circuit configuration eliminating as much as possible the selector valve for regulating simultaneous engagement, the valves 21, 22 which are a few selector valves for performing fail-safe can be controlled to avoid the engagement of the clutch not to be engaged until the occurrence of the low voltage failure is determined after shifting to the forward third gear speed stage. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a control device for an automatic transmission mounted on a vehicle or the like, and more specifically, it is possible to avoid unintentional engagement of frictional engagement elements at the time of a low-voltage failure while having a simple circuit configuration. The present invention relates to a control device for an automatic transmission.

  In general, in a multi-stage automatic transmission mounted on a vehicle or the like, each gear position is controlled by controlling the rotation state of each rotation element of the transmission gear mechanism by the engagement state of a plurality of friction engagement elements. The engagement pressure of the plurality of friction engagement elements is controlled by electrically adjusting the engagement pressure using a solenoid valve and supplying the pressure to the hydraulic servo of each friction engagement element. .

  In such an automatic transmission, the hydraulic control device that controls the transmission mechanism operates a solenoid valve arranged in each supply oil passage from the hydraulic source to the hydraulic servo of each friction engagement element according to the shift stage. Therefore, the circuit configuration for controlling the hydraulic pressure supply to the hydraulic servo is adopted. For this reason, in order to cope with unintentional frictional engagement elements engaged by a failure of a signal for operating each solenoid valve or a failure (valve stick, etc.) of each valve itself, an oil passage on the upstream side of each solenoid valve. In addition, there is one in which a fail-safe switching valve (cut-off valve) is arranged. As an example employing such a circuit configuration, one described in Patent Document 1 is known.

  In the hydraulic control device described in Patent Document 1, first and second hydraulic servos that are connected to first and second oil passages that are connected to a hydraulic power source and operate first and second clutches (friction engagement elements). And first and second linear solenoid valves that are disposed on the first and second oil passages and operate to engage / release by supplying / discharging hydraulic pressure to the first and second hydraulic servos, and the oil And a cutoff valve that is disposed on the road and cuts off the hydraulic pressure from the hydraulic pressure source to the second hydraulic servo by using the hydraulic pressure downstream of the first linear solenoid valve as a signal pressure. A shift stage formed by disposing a supply relay valve that cuts off the hydraulic pressure to the first hydraulic servo and the signal pressure in the first oil passage, engaging the first clutch, and releasing the second clutch. Sometimes, when a failure occurs in which the hydraulic pressure is supplied to the second hydraulic servo of the second clutch, the engagement pressure supplied to the second hydraulic servo is cut off by the cut-off valve, so that the second clutch is engaged. In combination, it is possible to prevent other gear positions from being formed.

JP 2001-248718 A

  By the way, in the failure to be avoided in the automatic transmission, in addition to the failure of each solenoid valve operation signal and the failure of each valve itself, the battery mounted on the vehicle and supplying power is weak, or the alternator is There is a low voltage failure that occurs when a battery fails to charge properly. When such a low voltage failure occurs, the current flowing through each solenoid valve may decrease as the voltage decreases. That is, in such a case, there is a risk that the normally open (N / O) type linear solenoid valve arranged in the hydraulic circuit may gradually increase the hydraulic pressure due to a voltage drop, or a normally closed (N / C) type linear solenoid valve. There is a risk that the solenoid valve gradually lowers the hydraulic pressure due to the voltage drop. In that case, there is a possibility that the hydraulic pressure is supplied to the hydraulic servo of the friction engagement element that should not be engaged at that time.

  Here, according to the hydraulic control device described in Patent Document 1, since the oil passage is provided with many switching valves other than the solenoid valve, such as the above-described cutoff valve and supply relay valve, the low pressure as described above. At the time of a voltage failure, by switching these switching valves, it is possible to suppress the engagement of unnecessary frictional engagement elements at that time, and to avoid problems such as engagement of frictional engagement elements that should not be engaged. . However, the presence of these many switching valves complicates the circuit configuration, increases the number of parts, and makes the device more compact, and may increase the cost.

  For this reason, it is conceivable to eliminate the switching valve other than the solenoid valve as much as possible to reduce the size of the hydraulic control device. However, in the case of such a circuit configuration, as described above when a low voltage failure occurs, There is a need to provide means for avoiding the failure of engaging frictional engagement elements that should not be engaged.

  Therefore, the present invention should be engaged when a low-voltage failure occurs, while having a simple circuit configuration in which a switching valve for avoiding engagement of a friction engagement element that should not be engaged is eliminated as much as possible. It is an object of the present invention to provide a control device for an automatic transmission that can reliably prevent the engagement of non-frictional engagement elements.

The present invention according to claim 1 (see, for example, FIGS. 1 to 7) is the first, second and third friction engagement elements (C-1, C-2, C- 3) and
A normally closed first solenoid valve (SLC1) capable of supplying a first hydraulic pressure (P _SLC1 ) to the first hydraulic servo (41) of the first friction engagement element (C-1) when energized;
A normally open type second solenoid valve (SLC2) capable of supplying the second hydraulic pressure (P _SLC2 ) to the second hydraulic servo (42) of the second friction engagement element (C-2) when not energized;
A normally open type third solenoid valve (SLC3) _capable of supplying the third hydraulic pressure (P _SLC3 ) to the third hydraulic servo (43) of the third friction engagement element (C-3) when de-energized;
A fail-safe mechanism that allows the first and third frictional engagement elements (C-1, C-3) to be engaged during a solenoid all-off failure to form a predetermined speed (for example, the third forward speed). 21, 22, S1),
A low voltage state detector (77) for detecting a low voltage state of a battery (75) that supplies power to at least the first to third solenoid valves (SLC1, SLC2, SLC3);
A low voltage failure confirmation control means (71) for confirming that a low voltage failure has occurred when the low voltage state is detected by the low voltage state detection unit (77) and the low voltage state continues for a predetermined time; In an automatic transmission control device (1) comprising:
During the control by the low-voltage failure determination control means (71), the low-voltage failure occurrence is determined and determined by controlling the fail-safe mechanism (21, 22, S1) while shifting to the predetermined shift stage. Simultaneous engagement avoidance control means for avoiding simultaneous engagement of the first, second and third friction engagement elements (C-1, C-2, C-3) during the continuous low voltage state until (72)
The control apparatus (1) for an automatic transmission is characterized by the above.

  In the present invention, “simultaneous engagement” means “engagement of frictional engagement elements (for example, clutches) that should not be engaged” and “engagement of unintended frictional engagement elements (for example, clutches)”. ing.

The present invention according to claim 2 (see, for example, FIGS. 1 to 7), the fail-safe mechanism is:
A normally open type fourth solenoid valve (S1) capable of outputting the fourth hydraulic pressure (P _S1 ) when not energized;
A low speed stage that outputs a first preliminary hydraulic pressure (P _DC1 ) for the first hydraulic servo (41) according to the supply state of the first hydraulic pressure (P _SLC1 ) and the fourth hydraulic pressure (P _S1 ). It is switched between a side position (right half position in FIG. 4) and a high speed stage side position (left half position in FIG. 4) that outputs the second preliminary hydraulic pressure (P _DC2 ) for the second hydraulic servo (42). A preliminary speed change valve (21);
The first and second hydraulic pressures (P _SLC1 , P _SLC2 ) are changed to the first and second hydraulic pressures according to the supply states of the first hydraulic pressure (P _SLC1 ) and the fourth hydraulic pressure (P _S1 ). servo (41, 42) normal time position capable of feeding each of (left half position in FIG. 4) and the low voltage state detection unit (77) by the low-voltage state of the detection during the first preliminary oil pressure (P _DC1) A hydraulic supply switching valve (22) that can be switched to a position at the time of failure (right half position in FIG. 4) that can supply the first hydraulic servo (41)
The simultaneous engagement avoidance control means (72) shifts the hydraulic pressure supply switching valve (22) to which the first operating hydraulic pressure (P _SLC1 ) is continuously supplied after shifting to the predetermined shift speed (forward third speed). By switching the fourth solenoid valve (S1) to a non-energized state, the first preliminary hydraulic pressure (P _DC1 ) is supplied to the first hydraulic servo (41) instead of the first operating hydraulic pressure (P _SLC1 ). After waiting in a state where it can be switched to the position at the time of failure (right half position in FIG. 4), the first solenoid valve (SLC1) is switched to a non-energized state to supply the first operating hydraulic pressure (P _SLC1 ). By shutting off, the supply oil passage (c2) of the second hydraulic pressure (P _SLC2 ) to the second hydraulic servo (42) is shut off, and the first preliminary hydraulic pressure (P _DC1 ) is changed to the first hydraulic pressure. Servo (41) Then, the engagement of the first friction engagement element (C-1) is continued and the third hydraulic pressure (3) is controlled by the third solenoid valve (SLC3) to the third hydraulic servo (43). P _SLC3 ) is fixed to the predetermined shift speed (the third forward speed) by the engagement of the third friction engagement element (C-3).
A control device (1) for an automatic transmission according to claim 1.

According to a third aspect of the present invention (see, for example, FIGS. 1 and 6), the low voltage failure confirmation control means (71) is configured such that the fail-safe mechanism (21, 22, 22) is controlled by the simultaneous engagement avoidance control means (72). When it is determined that the normal determination condition that the voltage of the battery (75) has continued the predetermined voltage for a certain period of time after being fixed at the predetermined shift speed (the third forward speed) using S1) is satisfied. After the first solenoid valve (SLC1) is switched to the energized state and the fourth solenoid valve (S1) is switched to the energized state, the control is shifted to the normal control that can shift to a gear other than the predetermined gear. Comprising return control means (73) for performing return control;
A control device (1) for an automatic transmission according to claim 2.

According to a fourth aspect of the present invention (see, for example, FIGS. 1 and 6), when the occurrence of the low voltage failure is determined by the low voltage failure determination control means (71), the fail-safe mechanism (21, 22). , S1), and by providing fail-safe control means (78) for continuously performing the control to form the predetermined shift speed (the third forward speed) as the solenoid all-off fail.
The control device (1) for an automatic transmission according to any one of claims 1 to 3.

  In addition, although the code | symbol in the said parenthesis is for contrast with drawing, this is for convenience for making an understanding of invention easy, and has no influence on the structure of a claim. It is not a thing.

  According to the first aspect of the present invention, the simultaneous engagement avoidance control means shifts to a predetermined shift stage and controls the fail-safe mechanism during the control by the low voltage failure confirmation control means, thereby generating a low voltage failure. Since the simultaneous engagement of the first, second, and third frictional engagement elements during the low voltage state until the determination is made is avoided, the simultaneous engagement of the frictional engagement elements that should not be engaged is restricted. A simple circuit configuration that eliminates as many switching valves as possible has been established, but the occurrence of a low-voltage failure is confirmed after shifting a few switching valves arranged in the oil passage to a predetermined gear position for fail-safe operation. Until it is determined, control can be performed so as to avoid simultaneous engagement. As a result, in fail-safe when a low-voltage failure occurs, the predetermined shift speed can be maintained while reliably preventing the hydraulic pressure supply to the second friction engagement element that should not be engaged at the predetermined shift speed.

  According to the second aspect of the present invention, although the switching valve other than the first to fourth solenoid valves is made as simple as possible, the fourth solenoid valve and the first solenoid valve are not arranged in this order. The shift to the energized state and the switching operation of the preliminary shift stage switching valve and the hydraulic pressure supply switching valve ensure that the hydraulic pressure supply to the second friction engagement element that should not be engaged is reliably prevented in the low voltage state. A predetermined gear position can be maintained without a shock.

  According to the third aspect of the present invention, the low voltage failure determination control means is fixed at a predetermined shift stage by the simultaneous engagement avoidance control means using the fail safe mechanism, and then the battery voltage continues the predetermined voltage for a predetermined time. When it is determined that the normal determination condition is established, the first solenoid valve is switched to the energized state, and the fourth solenoid valve is switched to the energized state. Since the return control means for performing the return control to shift to the normal control to be obtained is provided, when the low voltage state of the battery is recovered, it is possible to quickly return to the normal running by the normal control according to the situation.

  According to the fourth aspect of the present invention, the fail-safe control unit controls the fail-safe mechanism when the low-voltage failure determination control unit determines that the low-voltage failure has occurred, thereby forming a predetermined shift stage. Therefore, if it is determined that a low voltage failure has occurred, the predetermined shift speed that has already been established is continued as it is. can do.

The block diagram which shows the control apparatus of the automatic transmission which concerns on this invention. The skeleton figure which shows the automatic transmission which concerns on this invention. The engagement table of this automatic transmission. The circuit diagram which shows the hydraulic control apparatus of the automatic transmission in embodiment of this invention. The main flowchart explaining the effect | action of this Embodiment. The sub-flowchart for demonstrating the effect | action of this Embodiment. The time chart which shows the relationship between the command hydraulic pressure at the time of the shift in this Embodiment, and an actual hydraulic pressure. The time chart which shows the relationship between the command hydraulic pressure at the time of gear shifting in a comparative example, and an actual hydraulic pressure.

  Hereinafter, a first embodiment according to the present invention will be described with reference to FIGS.

[Schematic configuration of automatic transmission]
First, a schematic configuration of an automatic transmission 3 to which the present invention can be applied will be described with reference to FIG. As shown in FIG. 1, an automatic transmission 3 suitable for use in, for example, an FF type (front engine, front drive) vehicle has an input shaft 8 of an automatic transmission that can be connected to an engine (not shown). A torque converter 4 and an automatic transmission mechanism 5 are provided around the axial direction of the input shaft 8.

  The torque converter 4 includes a pump impeller 4a connected to the input shaft 8 of the automatic transmission 3, and a turbine runner 4b to which the rotation of the pump impeller 4a is transmitted via a working fluid. The runner 4 b is connected to the input shaft 10 of the automatic transmission mechanism 5 disposed coaxially with the input shaft 8. Further, the torque converter 4 is provided with a lock-up clutch 7, and when the lock-up clutch 7 is engaged, the rotation of the input shaft 8 of the automatic transmission 3 causes the input shaft of the automatic transmission mechanism 5 to rotate. 10 is transmitted directly.

  The automatic transmission mechanism 5 includes a planetary gear SP and a planetary gear unit PU on the input shaft 10. The planetary gear SP is a so-called single pinion planetary gear that includes a sun gear S1, a carrier CR1, and a ring gear R1, and has a pinion P1 that meshes with the sun gear S1 and the ring gear R1.

  The planetary gear unit PU has a sun gear S2, a sun gear S3, a carrier CR2, and a ring gear R2 as four rotating elements. The long gearion PL that meshes with the sun gear S2 and the ring gear R2 and the sun gear S3 This is a so-called Ravigneaux type planetary gear that has meshing short pinions PS that mesh with each other.

  The sun gear S <b> 1 of the planetary gear SP is connected to a boss portion that is integrally fixed to the mission case 9, and the rotation is fixed. The ring gear R1 is in the same rotation as the rotation of the input shaft 10 (hereinafter referred to as “input rotation”). Further, the carrier CR1 is decelerated by the input rotation being decelerated by the fixed sun gear S1 and the input rotating ring gear R1, and the clutch C-1 (first friction engagement element) and the clutch C- 3 (third friction engagement element).

  The sun gear S2 of the planetary gear unit PU is connected to a brake B-1 formed of a band brake so as to be freely fixed to the transmission case 9, and is connected to the clutch C-3. Thus, the decelerated rotation of the carrier CR1 can be freely input. The sun gear S3 is connected to the clutch C-1, so that the decelerated rotation of the carrier CR1 can be input.

  Further, the carrier CR2 is connected to a clutch C-2 (second friction engagement element) to which the rotation of the input shaft 10 is input, and the input rotation can be input via the clutch C-2. Further, it is connected to the one-way clutch F-1 and the brake B-2, and the rotation in one direction with respect to the transmission case 9 is restricted via the one-way clutch F-1, and also via the brake B-2. The rotation can be fixed. The ring gear R2 is connected to a counter gear 11, and the counter gear 11 is connected to a drive wheel via a counter shaft and a differential device (not shown).

[Operation of each gear stage in automatic transmission]
Next, based on the above configuration, the operation of the automatic transmission mechanism 5 will be described with reference to FIGS.

  For example, in the D (drive) range and the first forward speed (1ST), as shown in FIG. 3, the clutch C-1 and the one-way clutch F-1 are engaged. Then, as shown in FIG. 2, the rotation of the carrier CR1 decelerated by the fixed sun gear S1 and the ring gear R1 as the input rotation is input to the sun gear S3 via the clutch C-1. Further, the rotation of the carrier CR2 is restricted in one direction (forward rotation direction), that is, the carrier CR2 is prevented from rotating in the reverse direction and is fixed. Then, the decelerated rotation input to the sun gear S3 is output to the ring gear R2 via the fixed carrier CR2, and the forward rotation as the first forward speed is output from the counter gear 11.

  During engine braking (coast), the brake B-2 is locked to fix the carrier CR2, and the forward first speed state is maintained by preventing the carrier CR2 from rotating forward. . Further, at the first forward speed, the one-way clutch F-1 prevents the carrier CR2 from rotating in the reverse direction and enables forward rotation, so that the first forward speed when switching from the non-traveling range to the traveling range, for example. Can be smoothly achieved by the automatic engagement of the one-way clutch F-1.

  At the second forward speed (2ND), as shown in FIG. 3, the clutch C-1 is engaged and the brake B-1 is locked. Then, as shown in FIG. 2, the rotation of the carrier CR1 decelerated by the fixed sun gear S1 and the ring gear R1 as the input rotation is input to the sun gear S3 via the clutch C-1. Further, the rotation of the sun gear S2 is fixed by the locking of the brake B-1. Then, the carrier CR2 is decelerated and rotated at a speed lower than that of the sun gear S3, the decelerated rotation input to the sun gear S3 is output to the ring gear R2 via the carrier CR2, and the forward rotation as the second forward speed is counter gear. 11 is output.

  In the third forward speed (3RD), as shown in FIG. 3, the clutch C-1 and the clutch C-3 are engaged. Then, as shown in FIG. 2, the rotation of the carrier CR1 decelerated by the fixed sun gear S1 and the ring gear R1 as the input rotation is input to the sun gear S3 via the clutch C-1. Further, the reduced rotation of the carrier CR1 is input to the sun gear S2 by the engagement of the clutch C-3. That is, since the reduction rotation of the carrier CR1 is input to the sun gear S2 and the sun gear S3, the planetary gear unit PU is directly connected to the reduction rotation, and the reduction rotation is output to the ring gear R2 as it is, and the forward rotation as the third forward speed is performed. Output from the counter gear 11.

  At the fourth forward speed (4TH), as shown in FIG. 3, the clutch C-1 and the clutch C-2 are engaged. Then, as shown in FIG. 2, the rotation of the carrier CR1 decelerated by the fixed sun gear S1 and the ring gear R1 as the input rotation is input to the sun gear S3 via the clutch C-1. Further, the input rotation is input to the carrier CR2 by engaging the clutch C-2. Then, due to the decelerated rotation input to the sun gear S3 and the input rotation input to the carrier CR2, the decelerated rotation is higher than the third forward speed and is output to the ring gear R2, and the forward rotation as the fourth forward speed is performed. Is output from the counter gear 11.

  At the fifth forward speed (5TH), as shown in FIG. 3, the clutch C-2 and the clutch C-3 are engaged. Then, as shown in FIG. 2, the rotation of the carrier CR1 decelerated by the fixed sun gear S1 and the ring gear R1 as the input rotation is input to the sun gear S2 via the clutch C-3. Further, the input rotation is input to the carrier CR2 by the engagement of the clutch C-2. Then, due to the decelerated rotation input to the sun gear S2 and the input rotation input to the carrier CR2, the rotation speed is slightly higher than the input rotation and is output to the ring gear R2, which is the forward rotation as the fifth forward speed. Is output from the counter gear 11.

  At the sixth forward speed (6TH), as shown in FIG. 3, the clutch C-2 is engaged and the brake B-1 is locked. Then, as shown in FIG. 2, the input rotation is input to the carrier CR2 by the engagement of the clutch C-2. Further, the rotation of the sun gear S2 is fixed by the locking of the brake B-1. Then, the input rotation of the carrier CR2 becomes higher than the forward fifth speed by the fixed sun gear S2, and is output to the ring gear R2, and the forward rotation as the sixth forward speed is output from the counter gear 11. .

  In the first reverse speed (REV), as shown in FIG. 3, the clutch C-3 is engaged and the brake B-2 is locked. Then, as shown in FIG. 2, the rotation of the carrier CR1 decelerated by the fixed sun gear S1 and the ring gear R1 as the input rotation is input to the sun gear S2 via the clutch C-3. Further, the rotation of the carrier CR2 is fixed by the locking of the brake B-2. Then, the decelerated rotation input to the sun gear S2 is output to the ring gear R2 via the fixed carrier CR2, and the reverse rotation as the first reverse speed is output from the counter gear 11.

  For example, in the P (parking) range and the N (neutral) range, the clutch C-1, the clutch C-2, and the clutch C-3 are released. Then, the carrier CR1, the sun gear S2, and the sun gear S3, that is, the planetary gear SP and the planetary gear unit PU are disconnected, and the input shaft 10 and the carrier CR2 are disconnected. Thereby, the power transmission between the input shaft 10 and the planetary gear unit PU is disconnected, that is, the power transmission between the input shaft 10 and the counter gear 11 is disconnected.

[Configuration of automatic transmission control device]
Next, the control device 1 for the automatic transmission will be described. As shown in FIG. 1, the control device 1 of the automatic transmission is configured so that the clutches C-1 and C-3 are activated by the operation of the corresponding hydraulic servos 41 and 43 when the linear solenoid valve SLC1 and the linear solenoid valve SLC3 are operated. Engagement forms a third forward speed (predetermined speed) that is one of the low speed side speeds (first forward speed to third forward speed), and when the linear solenoid valve SLC2 and the linear solenoid valve SLC3 are operated. The engagement of the clutches C-2 and C-3 by the operation of the corresponding hydraulic servos 42 and 43 causes one of the high speed gears (four forward speeds to six forward speeds) to be a high speed stage (5 forward speeds). Stage). The control device 1 has a control unit (ECU) 70, which is connected to each of the linear solenoid valves SLC1, SLC2, SLC3, SLB1, the solenoid valves S1, S2, etc. of the hydraulic control device 6 described above. It is connected. Signals from an accelerator opening sensor, an input shaft rotational speed sensor, an output shaft rotational speed (vehicle speed) sensor, and the like (not shown) are input to the control unit 70, and an engine rotational speed signal from the engine 2 and the engine Torque signal is input. In the present embodiment, the first clutch apply relay valve 21, the second clutch apply relay valve 22, and the solenoid valve S1 are engaged with the clutch C-1 and the clutch C-3 at the time of solenoid all-off failure. A fail-safe mechanism that enables formation of the third forward speed (predetermined shift speed) is configured. Note that the clutches C-1, C-2, and C-3, which are provided in the control device 1 of the automatic transmission and constitute the first, second, and third friction engagement elements, are simultaneously engaged during normal operation. There is no.

  The control unit 70 performs normal shift control using the linear solenoid valves SLC1, SLC2, SLC3, SLB1, etc., performs solenoid all-off fail control by an emergency control means 78 described later, and detects a voltage detection sensor (low voltage state). A detection unit) 77, a low voltage failure determination control unit 71, an emergency control unit (fail-safe control unit) 78, and a shift determination unit 74. The low voltage failure determination control means 71 has a simultaneous engagement avoidance control means 72, a return control means 73, and a low voltage failure detection counter 76. In the present embodiment, “simultaneous engagement” means “engagement of friction engagement elements (for example, clutch) that should not be engaged” and “engagement of unintended friction engagement elements (for example, clutch)”. Means.

  The voltage detection sensor 77 checks the voltage of the battery 75 that supplies power to the linear solenoid valves SLC1, SLC2, SLC3, SLB1, and the solenoid valves S1, S2, detects the low voltage state, and outputs a signal of the detection result. This is sent to the low voltage failure confirmation control means 71. The battery 75 is disposed in a vehicle on which the control device 1 for the automatic transmission, the engine 2 and the like are mounted.

  The low voltage failure determination control means 71 determines that a low voltage failure has occurred when the low voltage state is detected by the voltage detection sensor 77 and the low voltage state continues for a predetermined time (for example, 20 seconds). To do.

  The emergency control means 78 performs solenoid all-off fail control, and when the occurrence of a low voltage failure is confirmed by the low voltage failure confirmation control means 71, the first clutch apply relay valve 21, the second clutch By controlling a fail-safe mechanism comprising the apply relay valve 22 and the solenoid valve S1, fail-safe control means for continuously performing the control for forming the third forward speed (predetermined shift speed) as a solenoid all-off fail is configured. .

  The shift determination means 74 is a shift map (not shown) based on an accelerator opening detected by an accelerator opening sensor (not shown) and a vehicle speed detected by an output shaft speed sensor (not shown). With reference to FIG. 6, the first forward speed to the sixth forward speed are determined. That is, an upshift shift line and a downshift shift line (shift point) corresponding to the accelerator opening and the vehicle speed are recorded in the shift map, and when the accelerator opening and the vehicle speed at that time exceed these shift lines. The shift determination means 74 determines the shift. Then, the shift stage (current shift stage) determined by the shift determination unit 74 is transmitted as a signal to the low voltage failure determination control unit 71, the emergency control unit 78, and the like.

The simultaneous engagement avoidance control means 72 shifts to the third forward speed (predetermined speed) during the control by the low voltage failure determination control means 71, and the first clutch apply relay valve 21 and the second clutch apply relay valve. By simultaneously controlling the fail-safe mechanism including the solenoid valve S1 and the solenoid valve S1, the clutches C-1, C-2, and C-3 are simultaneously engaged while the low voltage state continues until the low voltage failure occurrence is determined. To avoid. That is, the simultaneous engagement avoidance control means 72 _switches the second clutch apply relay valve 22 that is continuously supplied with the control pressure (first hydraulic pressure) P _SLC1 after shifting to the third forward speed, and the solenoid valve S1 is not energized. It was allowed to stand in the switchable state by switching, failure-time position for supplying the first preliminary hydraulic pressure P _DC1 instead of the control pressure P _SLC1 to the hydraulic servo 41 (the right half position in FIG. 4), the linear solenoid valve By switching SLC1 to a non-energized state and shutting off the supply of the control pressure P _SLC1 , the oil passage (supply oil passage) c2 of the second operating oil pressure P _SLC2 to the hydraulic servo 42 is shut off, and the first preliminary oil pressure P continued engagement of the clutch C-1 by entering the _DC1 to the hydraulic servo 41, the control pressure to the hydraulic servo 43 in regulating pressure operated linear solenoid valve SLC3 (third operating hydraulic pressure) _{P S} Control is performed so that _LC3 is fixed to the third forward speed by engagement of the input clutch C-3.

  The return control means 73 is fixed to the third forward speed by the simultaneous engagement avoidance control means 72 using the fail safe mechanism (21, 22, S1), and then the voltage of the battery 75 continues the predetermined voltage for a predetermined time. When it is determined that the normal determination condition is established, the linear solenoid valve SLC1 is switched to the energized state, the solenoid valve S1 is switched to the energized state, and then the gears other than the third forward speed (predetermined shift speed) are switched. Return control is performed to shift to normal control that can shift gears. The normality determination condition is a condition for determining that the normal state has been restored when it is detected that a constant voltage (for example, 10 [V]) has continued for a certain period of time (for example, 1 second).

  The low voltage failure detection counter 76 samples whether or not the voltage Vo of the battery 75 is less than a constant voltage α (for example, 9 [V]) (Vo <α [V]) every predetermined time (for example, several seconds). When performed, when the state of Vo <α [V] is detected continuously for a certain period (for example, 1 second), the count is incremented by +1.

[Schematic configuration of hydraulic control unit]
Next, the hydraulic control device 6 will be described. First, generation parts such as a line pressure, a secondary pressure, a modulator pressure, and a range pressure that are not illustrated in the hydraulic control device 6 will be roughly described. The generation portions of the line pressure, secondary pressure, modulator pressure, and range pressure are the same as those of a general automatic transmission hydraulic control device, and are well-known and will be described briefly.

  The hydraulic control device 6 includes, for example, an oil pump, a manual shift valve, a primary regulator valve, a secondary regulator valve, a solenoid modulator valve, a linear solenoid valve SLT, and the like (not shown). For example, when the engine is started, When an oil pump that is rotationally connected to the pump impeller 4a of the torque converter 4 is driven in conjunction with the rotation of the engine, hydraulic pressure is generated by sucking oil from an oil pan (not shown) through a strainer.

Hydraulic pressure generated by the oil pump, on the basis of a signal pressure P _SLT of the linear solenoid valve SLT that is pressure regulating output according to the throttle opening degree, the pressure is adjusted to a line pressure P _L being discharged adjusted by the primary regulator valve . The line pressure P _L is the manual shift valve (range switching valve), the solenoid modulator valve, and more information is supplied to the linear solenoid valve SLC3 to be described later. The line pressure P _L supplied to the solenoid modulator valve of this is pressure regulated to a modulator pressure P _MOD to be substantially constant pressure by the valve, the modulator pressure P _MOD is and the linear solenoid valve SLT, details It is supplied as a source pressure for solenoid valves S1, S2, etc., which will be described later.

The pressure discharged from the primary regulator valve is adjusted to the secondary pressure _PSEC while being further discharged and adjusted by the secondary regulator valve, for example, and this secondary pressure _PSEC is supplied to, for example, a lubricating oil passage or an oil cooler. And also supplied to the torque converter 4 and used to control the lock-up clutch 7.

On the other hand, a manual shift valve (not shown) has a spool that is mechanically (or electrically) driven by a shift lever provided in a driver's seat (not shown), and the position of the spool is controlled by the shift lever. selected shift range (e.g. P, R, N, D) by being switched according to, to set the output state or non-output state of the line pressure P _L the input (drain).

In particular, when the D range based on the operation of the shift lever, the said line pressure P _L based on the position of the spool communicates with the input port and the forward range pressure output port to be input, the forward range pressure output line from the port pressure P _L is output as a forward range pressure (D range pressure) P _D. When based on the operation of the shift lever to the R (reverse) range, communicates with the input port and the reverse range pressure output port based on the position of the spool, the line pressure P _L rear proceeds range pressure output port reverse range Pressure (R range pressure) _PREV is output. Further, when the P range and the N range are set based on the operation of the shift lever, the input port, the forward range pressure output port and the reverse range pressure output port are blocked by the spool, and the forward range pressure output. port and the reverse range pressure output port are communicated with the drain port, that is, the non-output state D range pressure P _D and the R range pressure P _REV are drained (discharged).

[Detailed Configuration of Shift Control Part of Hydraulic Control Device]
Next, a portion for mainly performing shift control in the hydraulic control device 6 according to the present invention will be described with reference to FIG. In the present embodiment, in order to describe the spool position, the right half position shown in FIG. 4 is called a “right half position”, and the left half position is called a “left half position”.

  The hydraulic control device 6 includes the hydraulic servo 41 for the clutch C-1, the hydraulic servo 42 for the clutch C-2, the hydraulic servo 43 for the clutch C-3, the hydraulic servo 44 for the brake B-1, and the brake B-2. Four linear solenoid valves SLC1, SLC2, SLC3, SLB1 for directly supplying the output pressure adjusted as the engagement pressure to each of a total of five hydraulic servos of the hydraulic servo 45, and In addition to achieving the limp home function, the solenoid valve S1, the solenoid valve S2, and the first clutch apply are used to switch the output pressure of the linear solenoid valve SLC2 to the hydraulic servo 42 of the clutch C-2 or the hydraulic servo 45 of the brake B-2. Relay valve 21, second clutch apply relay valve 22, C-2 relay valve 23, B-2 relay It is configured to include a Barubu 24 or the like.

Oil path a1, an oil passage a4 shown in FIG. 4, the oil passage a5 is configured to forward range pressure P _D is connected the forward range pressure output port of the manual shift valve described above (not shown) may enter In addition, a reverse range pressure output port (not shown) of the manual shift valve is connected to the oil passage l so that the reverse range pressure _PREV can be input. Further, the oil passage d, the primary regulator valve and the line pressure P _L from the (not shown) is input, additionally to the oil passage g1, the modulator pressure P _MOD from the modulator valve (not shown) is input It is configured.

  Of these, the oil passage a1 is connected to an input port 21e of a first clutch apply relay valve 21, which will be described in detail later, through an oil passage a2, and a check valve 50 and an orifice 60 are provided. The oil passage a1 is connected to the accumulator 30 through an oil passage a3 and to the linear solenoid valve SLC1. The accumulator 30 includes a case 30c, a piston 30b disposed inside the case 30c, a spring 30s that urges the piston 30b, and an oil chamber 30a formed between the case 30c and the piston 30b. It is comprised.

The linear solenoid valve (first solenoid valve) SLC1 is of a non-energized in a non-output state when normally closed (N / C) type, an input port SLC1a via the oil path a1 inputs the forward range pressure P _D If, and an output port SLC1b to output a control pressure (a first working fluid _{pressure) P SLC1} to the hydraulic servo 41 by regulating the forward range pressure _{P D} as an engagement pressure _{P C1.} That is, the linear solenoid valve SLC1 is cut off from the input port SLC1a and the output port SLC1b when not energized, and is in a non-output state. the communication amount between the ports SLC1a and the output port SLC1b (the opening amount) is increased in response to the finger command value, that is, is configured so as to output the engagement pressure P _C1 in accordance with the command value. An output port SLC1b of the linear solenoid valve SLC1 is connected to an input port 22c of a second clutch apply relay valve 22 described later via an oil passage b1.

On the other hand, the linear solenoid valve (second solenoid valve) SLC2 is input port consists normally open (N / O) type that attains an outputting state when being de-energized, via a oil passage a4 inputs the forward range pressure P _D Yes and SLC2a, and an output port SLC2b to output a control pressure (second operating hydraulic _{pressure) P SLC2} to the hydraulic servo 42 by regulating the forward range pressure _{P D} as an engagement pressure _{P C2} (or an engagement pressure _{P B2)} is doing. That is, the linear solenoid valve SLC2 is in an output state in which the input port SLC2a and the output port SLC2b are communicated when not energized, and when energized based on a command value from the control unit (ECU) 70, the input port SLC2a and the output port SLC2b Is reduced in accordance with the command value (that is, the opening amount is reduced), that is, the engagement pressure P _C2 (or P _B2 ) in accordance with the command value can be output. The output port SLC2b of the linear solenoid valve SLC2 is connected to an input port 22f of a second clutch apply relay valve 22 described later via an oil passage c1.

The linear solenoid valve (third solenoid valve) SLC3 is a normally open type that attains an outputting state when being de-energized, the input port SLC3a which inputs the line pressure P _L via a oil passage d, the line pressure P _L and an output port SLC3b to output a control pressure (third operating hydraulic _{pressure) P SLC3} to the hydraulic servo 43 as an engagement pressure _{P C3} and by regulating the. That is, the linear solenoid valve SLC3 is in an output state in which the input port SLC3a and the output port SLC3b are communicated when not energized, and when energized based on a command value from the control unit (ECU) 70, of the amount of communication is reduced in response to the finger command value (i.e. aperture openings amount), that is, is configured so as to output the engagement pressure P _C3 in accordance with the command value. The output port SLC3b of the linear solenoid valve SLC3 is connected to the hydraulic servo 43 of the clutch C-3 via an oil passage e1. In addition, a check valve 53 and an orifice 63 are disposed in the oil passage e1, and an oil chamber 33a of the C-3 damper 33 is connected through the oil passage e2. Since the C-3 damper 33 has the same configuration as the accumulator 30 described above and is a general damper device, detailed description thereof is omitted.

The linear solenoid valve SLB1 is of a normally closed type that is in the non-output state when de-energized, the input port SLB1a which via a oil passage a5 inputs the forward range pressure P _D, by regulating the forward range pressure P _D and an output port SLB1b to output as the engagement pressure _{P B1} control pressure _{P SLB1} to the hydraulic servo 44 Te. In other words, the linear solenoid valve SLB1 shuts off the input port SLB1a and the output port SLB1b when not energized and enters a non-output state, and when energized based on a command value from the control unit (ECU) 70, the input port SLB1a and output port The amount of communication with the SLB 1b (amount of opening) is increased according to the command value, that is, the engagement pressure P _B1 according to the command value can be output. The output port SLB1b of the linear solenoid valve SLB1 is connected to the hydraulic servo 44 of the brake B-1 via an oil passage f1. In addition, a check valve 54 and an orifice 64 are disposed in the oil passage f1, and an oil chamber 34a of the B-1 damper 34 is connected through the oil passage f2.

Solenoid valve (fourth solenoid valve) S1 is a normally open type that attains an outputting state when being de-energized, the input port S1a which inputs the modulator pressure P _MOD through the oil passages g1, g2, when de-energized (i.e. It has the OFF time) and an output port S1b for outputting the modulator pressure _{P MOD} substantially as it is as a signal pressure (fourth operating _{pressure) P S1.} The output port S1b is connected to the oil chamber 21a of the first clutch apply relay valve 21 via the oil passages h1 and h2, and the oil of the second clutch apply relay valve 22 is provided via the oil passages h1 and h3. In addition to being connected to the chamber 22a, it is connected to the input port 24c of the B-2 relay valve 24 via the oil passage h4.

The solenoid valve S2 is of a normally closed type that is in a non-output state when not energized, the input port S2a that inputs the modulator pressure P _MOD via the oil passages g1 and g3, and the modulator when energized (that is, when ON). And an output port S2b for outputting the pressure P _MOD as the signal pressure P _S2 almost as it is. The output port S2b is connected to the oil chamber 24a of the B-2 relay valve via the oil passage i.

  The first clutch apply relay valve (preliminary shift speed switching valve) 21 is provided with two spools 21p and 21q, a spring 21s that biases the spool 21p upward in the figure, and a direction in which the spools 21p and 21q are separated from each other. And an oil chamber 21a above the spool 21q, an oil chamber 21d below the spool 21p, and an oil chamber 21c between the spools 21p and 21q. An oil chamber 21b formed by a difference in the diameter of the land portion of the spool 21q (a difference in pressure receiving area), and further includes an input port 21e, an input port 21f, an input port 21g, and an input port 21h. The output port 21i, the output port 21j, and the drain port EX are configured.

  The first clutch apply relay valve 21 has an input port 21e and an output port 21j communicating with each other when the spools 21p and 21q are set to the left half position (high speed stage position), and the input port 21e and the output port. When 21i is cut off and set to the right half position (low speed stage position), the input port 21e and the output port 21i are communicated with each other, and the output port 21j and the drain port EX are communicated with each other. Has been. Further, the input port 21h is blocked when the spool 21p is set to the left half position, and the input port 21g is blocked when the spool 21q is set to the right half position.

As described above, the oil chamber 21a is connected to the output port S1b of the solenoid valve S1 via the oil passages h1 and h2, and the oil chamber 21b is connected to the output port 21f described later via the oil passage b4. The two-clutch apply relay valve 22 is connected to the output port 22 i. The aforementioned input port 21e, and is input the forward range pressure P _D via the oil path a1, a2, the output port 21j of the spool 21p is communicated with the input port 21e when the left half position, the oil passage j To the input port 22 h of the second clutch apply relay valve 22. Further, when the spool 21p is in the right half position, an output port 21i communicating with the input port 21e includes an input port 21g via the oil passages k1 and k2, and an input port 21h via the oil passages k1, k2 and k3. In other words, the output port 21i is connected to the oil chamber 21c regardless of the positions of the spools 21p and 21q. Further, the output port 21i is connected to an input port 22e of a second clutch apply relay valve 22 described later via an oil passage k1. The oil chamber 21d is connected to an output port 23c of a C-2 relay valve 23 via an oil passage c5. A check valve 55 and an orifice 65 are provided in the oil passage c5. Yes.

  The second clutch apply relay valve (hydraulic supply switching valve) 22 includes a spool 22p and a spring 22s that urges the spool 22p upward in the figure, and an oil chamber above the spool 22p in the figure. 22a and an oil chamber 22b below the spool 22p in the figure, and further, an input port 22c, an output port 22d, an input port 22e, an input port 22f, an output port 22g, and an input port 22h and an output port 22i.

  When the spool 22p is set to the left half position (normal position), the second clutch apply relay valve 22 communicates with the input port 22c, the output port 22d, and the output port 22i, and the input port 22f and the output port. 22g communicates with each other, and when the input port 22e and the input port 22h are shut off and set to the right half position (failure position), the input port 22e and the output port 22d communicate with each other The port 22h and the output port 22g are communicated with each other, and the input port 22c, the output port 22i, and the input port 22f are blocked.

  As described above, the oil chamber 22a is connected to the output port S1b of the solenoid valve S1 via the oil passages h1 and h3, and the input port 24c of the B-2 relay valve 24 described later via the oil passage h4. It is connected to the. The input port 22c is connected to the output port SLC1b of the linear solenoid valve SLC1 through an oil passage b1, and the output port 22d communicating with the input port 22c when the spool 22p is in the left half position It is connected to the hydraulic servo 41 of the clutch C-1 via b2. A check valve 51 and an orifice 61 are disposed in the oil passage b2, and an oil chamber 31a of the C-1 damper 31 is connected through the oil passage b3. Similarly, when the spool 22p is in the left half position, an output port 22i communicating with the input port 22c is connected to the input port 21f of the first clutch apply relay valve 21 via the oil passage b4, and the oil passage It is connected to the oil chamber 22b through b4 and b5. On the other hand, the input port 22f is connected to the output port SLC2b of the linear solenoid valve SLC2 via the oil passage c1, and the input port 22h is connected to the first clutch apply relay valve 21 via the oil passage j. It is connected to the output port 21j. An output port 22g communicating with the input port 22f when the spool 22p is in the left half position and communicating with the input port 22h when the spool 22p is in the right half position is connected via an oil passage (supply oil passage) c2. It is connected to an input port 23b of a C-2 relay valve 23 described later. A check valve 52 and an orifice 62 are disposed in the oil passage c2, and an oil chamber 32a of a C2-B2 damper 32 is connected through an oil passage c4.

  The C-2 relay valve 23 includes a spool 23p and a spring 23s that urges the spool 23p upward in the figure, and an oil chamber 23a above the spool 23p in the figure. Further, the configuration includes an input port 23b, an output port 23c, an output port 23d, an output port 23e, and a drain port EX.

  When the spool 23p is set to the left half position, the C-2 relay valve 23 communicates with the input port 23b, the output port 23c, and the output port 23e, and communicates with the output port 23d and the drain port EX. When set to the right half position, the input port 23b and the output port 23d are communicated with each other, and the output port 23c and the output port 23e are communicated with the drain port EX.

  The oil chamber 23a is connected to an output port 24b of a B-2 relay valve 24 described later via an oil passage h5. The input port 23b is connected to the output port 22g of the second clutch apply relay valve 22 via an oil passage c2, and an output port 23e that communicates with the input port 23b when the spool 23p is in the left half position. It is connected to the hydraulic servo 42 of the clutch C-2 via the path c3. Similarly, the output port 23c communicating with the input port 23b when the spool 23p is in the left half position is connected to the oil chamber 21d of the first clutch apply relay valve 21 via the oil passage c5. A check valve 55 and an orifice 65 are disposed in the oil passage c5. The output port 23d that communicates with the input port 23b when the spool 23p is in the right half position is connected to the input port 24e of the B-2 relay valve 24 via the oil passage m.

  The B-2 relay valve 24 has a spool 24p and a spring 24s that urges the spool 24p upward in the figure, and an oil chamber 24a in the upper part of the spool 24p in the figure. The output port 24b, the input port 24c, the input port 24d, the input port 24e, the output port 24f, the output port 24g, and the drain port EX are configured.

  When the spool 24p is set to the left half position, the B-2 relay valve 24 communicates with the input port 24d, the output port 24f, and the output port 24g, and communicates with the output port 24b and the drain port EX. At the same time, when the input port 24c is shut off and set to the right half position, the input port 24c and the output port 24b communicate with each other, and the input port 24e and the output port 24g communicate with each other, and the input port 24d, The drain port EX is configured to be shut off.

The oil chamber 24a is connected to the output port S2b of the solenoid valve S2 through an oil passage i. The input port 24d is connected to a reverse range pressure output port (not shown) of a manual shift valve from which a reverse range pressure _PREV is output via an oil passage l. The input port 24e is connected to an oil passage. m is connected to the output port 23d of the C-2 relay valve 23, and communicates with the input port 24d when the spool 24p is in the left half position, and the spool 24p is in the right half position with the input port 24e. The output port 24g that communicates with the brake B-2 is connected to the hydraulic servo 45 of the brake B-2 via the oil passage n. That is, the hydraulic servo 45 of the brake B-2 is connected to the reverse range pressure output port ( (Not shown), or connected to the output port SLC2b of the linear solenoid valve SLC2. Further, as described above, the input port 24c is connected to the output port S1b of the solenoid valve S1 via the oil passage h4, the oil chamber 22a of the second clutch apply relay valve 22, and the oil passages h1 and h3. An output port 24b that communicates with the input port 24c when the spool 24p is in the right half position is connected to the oil chamber 23a of the C-2 relay valve 23 via an oil passage h5. An output port 24f that communicates with the input port 24d when the spool 24p is in the left half position is connected to the oil chamber of the primary regulator valve via an oil passage (not shown). It is configured to increase the line pressure P _L during reverse travel by the action of P _REV.

As described above, the linear solenoid valve SLC1 is a normally closed first solenoid valve that can supply the control pressure (first hydraulic pressure) P _SLC1 to the hydraulic servo (first hydraulic servo) 41 of the clutch C-1 when energized. Is configured. The linear solenoid valve SLC2 is a normally open type second solenoid valve that can supply the control pressure (second hydraulic pressure) _PSLC2 to the hydraulic servo (second hydraulic servo) 42 of the clutch C-2 when not energized. Yes. The linear solenoid valve SLC3 constitutes a normally open third solenoid valve that can supply the control pressure (third hydraulic pressure) _PSLC3 to the hydraulic servo (third hydraulic servo) 43 of the clutch C-3 when the power is not supplied. Yes. The solenoid valve S1 constitutes a normally open type fourth solenoid valve that can output a signal pressure (fourth operating oil pressure) _PS1 when not energized.

Further, the first clutch apply relay valve 21 has a first preliminary hydraulic pressure P for the hydraulic servo 41 according to the supply state of the control pressure (first hydraulic pressure) _PSLC1 and the signal pressure (fourth hydraulic pressure) _PS1. Preliminary shift to be switched between a low speed stage position that outputs _DC1 (right half position in FIG. 4) and a high speed stage position that outputs second preliminary hydraulic pressure _PDC2 for the hydraulic servo 42 (left half position in FIG. 4). A stage switching valve is configured. Further, the second clutch apply relay valve 22 supplies the control pressures P _SLC1 and P _SLC2 to the hydraulic servo in accordance with the supply state of the control pressure (first hydraulic pressure) P _SLC1 and the signal pressure (fourth hydraulic pressure) _PS1. The normal position (left half position in FIG. 4) that can be supplied to each of 41 and 42, and the failure position that can supply the first preliminary hydraulic pressure _PDC1 to the hydraulic servo 41 when the voltage detection sensor 77 detects a low voltage state ( The hydraulic pressure supply switching valve is configured to be switched to the right half position in FIG.

[Hydraulic control device operation]
Next, the operation of the hydraulic control device 6 according to the present embodiment will be described.

For example, when the ignition is turned on by the driver, the hydraulic control of the hydraulic control device 6 is started. First, when the selected position of the shift lever is, for example, the P range or the N range, the normal open type linear solenoid valve SLC2, linear solenoid valve SLC3, and solenoid valve S1 are energized by an electrical command from the control unit 70. The input port and the output port are shut off. Then, for example, when the engine is started, hydraulic pressure is generated by the rotation of the oil pump based on the engine rotation (not shown), the hydraulic pressure by the primary regulator valve and the solenoid modulator valve as described above, Ya line pressure P _L are respectively pressure regulating output to the modulator pressure P _MOD, together with the input port SLC3a and the line pressure P _L of the linear solenoid valve SLC3 is input through the input port and the oil passage d of the manual shift valve (not shown), an oil passage g1 , the input port S1a of the solenoid valves S1, S2 via the g2, g3, the modulator pressure _{P MOD} is input to the S2a.

Then, for example when the driver is in the D range position shift lever from the N range position, the manual shift valve oil passage from the forward range pressure output port of a1, a4, a5 in the forward range pressure P _D is output, the forward range pressure _{P D} is the linear solenoid valve SLC1 via the oil passage a1, the linear solenoid valve SLC2 via the oil passage a4, the linear solenoid valve SLB1 via the oil passage a5, via the oil paths a1, a2 1 Each is input to the clutch apply relay valve 21.

The aforementioned oil passage a1, is disposed and a check valve 50 and the orifice 60, since the check valve 50 is opened by the forward range pressure P _D, the supply of the forward range pressure P _D for the linear solenoid valve SLC1 is discharged It becomes rapid compared with time. Moreover, the forward range pressure P _D supplied to the oil passage a1 is connected via an oil passage a3 is input to the oil chamber 30a of the accumulator 30, by the accumulator 30, the forward range pressure P _D supplied to the linear solenoid valve SLC1 Accumulate pressure.

Further, since the forward range pressure P _D from the oil passage a2 is the first clutch apply relay valve 21 is input to the input port 21e, the solenoid valve S1 is not has been outputted signal pressure P _S1 ON, switching to the D range was initially (initial N-D shift) is in the left half position by the biasing force of the spring 21s, and outputs the forward range pressure P _D to the oil passage j from the output port 21j, but similarly the solenoid valve S1 Since the signal pressure _PS1 is not output after being turned on, the input port 22h is shut off in the second clutch apply relay valve 22 which is in the left half position by the biasing force of the spring 22s.

Then, for example, the forward first speed is judged by the control unit 70, the linear solenoid valve SLC1 is turned ON by the electrical control of the control unit 70, the regulating pressure control forward range pressure P _D is input to the input port SLC1a to control the pressure _{P SLC1} output from the gradually increases so that the output port SLC1b as the engagement pressure _{P C1,} the second clutch apply control pressure _{P SLC1} (engagement pressure _{P C1)} via the oil passage b1 It is input to the input port 22 c of the relay valve 22.

Then, the second clutch apply relay valve 22 in the left half position outputs the control pressure P _SLC1 input to the input port 22c from the output port 22i and also from the output port 22d. The control pressure P _SLC1 output from the output port 22i is input to the oil chamber 22b via the oil passages b4 and b5, and locks the second clutch apply relay valve 22 to the left half position and via the oil passage b4. Input to the oil chamber 21b of the first clutch apply relay valve 21 and press the spools 21p and 21q downward in the figure against the urging force of the spring 21s to switch the first clutch apply relay valve 21 to the right half position. .

The first clutch apply relay valve 21 in which the spools 21p and 21q are switched to the right half position causes the spool 21q to be biased by the spring 21t by the control pressure _PSLC1 output from the output port 22i of the second clutch apply relay valve 22. contrary to it are pressed downward in the figure, the forward range pressure _{P D} input from the input port 21e is output from the output port 21i as the first preliminary oil pressure _{P DC1,} oil paths k1, k2, k3 and the input Since the spool 21q is input to the oil chamber 21c via the port 21h, the spool 21q is switched upward in the figure by the hydraulic pressure acting on the oil chamber 21c and the urging force of the spring 21t, that is, the spool 21p and the spool 21q Is locked in a separated state. Note that the first preliminary hydraulic pressure P _DC1 (that is, the forward range pressure P _D ) input from the oil passage k1 to the input port 22e of the second clutch apply relay valve 22 is blocked at the input port 22e.

As described above, the control pressure P _SLC1 input from the linear solenoid valve SLC1 to the input port 22c of the second clutch apply relay valve 22 is applied to the hydraulic servo 41 from the output port 22d via the oil passage b2. _C1 is output, and the clutch C-1 is engaged. Thereby, the forward first speed is achieved in combination with the locking of the one-way clutch F-1.

The oil passage b2 is provided with a check valve 51 and an orifice 61. When supplying the _engagement pressure P _C1 (control pressure P _SLC1 ) to the hydraulic servo 41, the check valve 51 is closed, only through orifice 61 gently supply an oil pressure, and adapted rapidly discharged than when supplying open the check valve 51 when discharging the engagement pressure P _C1 from the hydraulic servo 41 . Moreover, the engagement pressure _{P C1} supplied to the oil passage b2 through an oil passage b3 is input to the oil chamber 31a of the C1 damper 31, by the C1 damper 31, it is supplied to and discharged from the hydraulic servo 41 It prevents pulsation of Rukakarigo圧P _C1, and absorbs a surge pressure (a sharp fluctuating pressure), for example.

[Operation in engine brake at the first forward speed]
Further, for example, when the control unit 70 determines that the first forward speed engine brake is performed, the solenoid valve S2 is turned on and the solenoid valve S1 is turned off by the electrical command from the control unit 70. Further, the linear solenoid valve SLC2 is pressure-controlled. When the solenoid valve S2 is turned ON, the modulator pressure P _MOD input to the input port S2a via the oil passages g1 and g3 is output from the output port S2b as the signal pressure _{PS2 and} passes through the oil passage i. Then, it is input to the oil chamber 24a of the B-2 relay valve 24, the spool 24p is switched downward in the figure against the urging force of the spring 24s, and the B-2 relay valve 24 is set to the right half position.

When the solenoid valve S1 is turned off, the modulator pressure P _MOD input to the input port S1a via the oil passages g1 and g2 is output from the output port S1b as the signal pressure P _S1 and the oil passage h1, The oil chamber 21a of the first clutch apply relay valve 21 through h2, the oil chamber 22a of the second clutch apply relay valve 22 through oil passages h1 and h3, and the B-2 relay valve 24 through the oil passage h4. Is further input to the oil chamber 23a of the C-2 relay valve 23 via the oil path h5 from the output port 24b of the B-2 relay valve 24 set to the right half position.

Then, the C-2 relay valve 23 is switched to the lower half position in the drawing against the urging force of the spring 23s by the signal pressure _PS1 input to the oil chamber 23a, so that the spool 23p is switched downward. In the first clutch apply relay valve 21, the signal pressure _PS1 is input to the oil chamber 21a, so that the spool 21q is switched downward in the drawing to the right half position. It remains in the same right half position as in the first forward speed, and has no particular effect. The second clutch apply relay valve 22 is signal pressure _{P S1} to the oil chamber 22a is input, the above-described oil chamber 22b of the engagement pressure _{P C1} (control pressure _{P SLC1)} and the biasing force of the spring 22s , The spool 22p remains locked in the left half position.

Then, the linear solenoid valve SLC2 control is regulation control, the control pressure _{P SLC2} is output from the output port SLC2b, control pressure _{P SLC2} is second clutch apply locked to the left half position via the oil path c1 is input to the input port 22f of the relay valve 22, is outputted to the oil passage c2 from the output port 22g as the engagement pressure _{P B2.}

The engagement pressure P _B2 output to the oil passage c2 is input to the input port 23b of the C-2 relay valve 23 that is in the right half position, and is output from the output port 23d. Further, the engagement pressure P _B2 is input to the input port 24e of the B-2 relay valve 24 that is in the right half position via the oil passage m, is output from the output port 24g, and passes through the oil passage n. Is input to the hydraulic servo 45, and the brake B-2 is locked. Thus, in combination with the engagement of the clutch C-1, the first forward speed engine brake is achieved.

The oil passage c2 is provided with a check valve 52 and an orifice 62. When supplying the engagement pressure P _B2 to the hydraulic servo 45 of the brake B-2, the check valve 52 is closed and the orifice The oil pressure is gently supplied via only 62, and at the time of discharge described later, the check valve 52 is opened to rapidly discharge the oil pressure in the oil passage c2. Further, the engagement pressure P _B2 supplied to the oil passage c2 is input to the oil chamber 32a of the C2-B2 damper 32 via the oil passage c4, and is supplied to and discharged from the hydraulic servo 45 by the C2-B2 damper 32. It prevents pulsation of Rukakarigo圧P _B2, and absorbs a surge pressure (a sharp fluctuating pressure), for example.

For example, when the control unit 70 determines that the first forward speed is positively driven, that is, when it is determined that the engine brake state is released, the solenoid valve S2 is turned OFF and the solenoid valve S1 is turned ON. The SLC2 is closed in the ON (energized) form, and the control pressure P _SLC2 as the engagement pressure P _B2 is set to 0 and drained. Moreover, the engagement pressure _{P B2} of the hydraulic servo 45 of the brake B2, since the B2 relay valve 24 by OFF of the solenoid valve S2 is switched to the left half position, the input port 24d, the oil path l, the manual shift valve Is discharged from the drain port of the manual shift valve through a reverse range pressure output port (not shown), whereby quick draining is performed faster than draining through the linear solenoid valve SLC2, and the brake B- 2 is released quickly. Note that the oil pressure in the oil passage m is discharged from the drain port EX of the C-2 relay valve 23 switched to the left half position, and the oil pressure in the oil passages c1 and c2 is from the drain port EX of the linear solenoid valve SLC2. Discharged.

[Operation at 2nd forward speed]
Next, for example, when the control unit 70 determines the second forward speed from the state of the first forward speed, the electric command from the control unit 70 is the same as in the case of the first forward speed (during engine braking). Excluding), the pressure regulation control of the linear solenoid valve SLB1 is performed while the pressure regulation state of the linear solenoid valve SLC1 is maintained in a state where the solenoid valve S1 is turned on and the solenoid valve S2 is turned off.

That is, when the linear solenoid valve SLB1 is pressure regulation control, the control pressure _{P SLB1} is output from the output port SLB1b as the engagement pressure _{P B1,} and input to the hydraulic servo 44 via the oil passage f1, brakes B1 Is locked. Thereby, the forward second speed is achieved in combination with the engagement of the clutch C-1.

The oil passage f1 is provided with a check valve 54 and an orifice 64. When supplying the engagement pressure P _B1 to the hydraulic servo 44 of the brake B-1, the check valve 54 is closed and the orifice is passed. When the hydraulic pressure is slowly supplied through only the hydraulic pressure 64 and the engagement pressure P _B1 is discharged from the hydraulic servo 44, the hydraulic pressure is discharged more rapidly than when the check valve 54 is opened and supplied. ing. Further, the engagement pressure P _B1 supplied to the oil passage f1 is input to the oil chamber 34a of the B-1 damper 34 via the oil passage f2, and is supplied to and discharged from the hydraulic servo 44 by the B-1 damper 34. It prevents pulsation of Rukakarigo圧P _B1, and absorbs a surge pressure (a sharp fluctuating pressure), for example.

[Operation at 3rd forward speed]
Subsequently, for example, when the control unit 70 determines the third forward speed from the state of the second forward speed, the solenoid valve S1 is similarly turned on and the solenoid valve S2 is turned on by an electrical command from the control unit 70. While the pressure regulation state of the linear solenoid valve SLC1 is maintained in the OFF state, the linear solenoid valve SLB1 is closed while being turned off, and the pressure regulation control of the linear solenoid valve SLC3 is performed.

That is, first, the release control of the brake B-1 is performed by the pressure regulation control of the linear solenoid valve SLB1, that is, the engagement pressure P _B1 (control pressure P _SLB1 ) of the hydraulic servo 44 of the brake B-1 _passes through the oil passage f1. Through the drain port EX of the linear solenoid valve SLB1, the brake B-1 is released. Also, one of the linear solenoid valve SLC3 is, ON (energized) by the control pressure _{P SLC3} is 0 pressure regulation control from the state which has been closed so that the pressure is performed, the control pressure _{P SLC3} engagement pressure _{P C3} Is output from the output port SLC3b and input to the hydraulic servo 43 via the oil passage e1, and the clutch C-3 is engaged. Thereby, the forward third speed is achieved in combination with the engagement of the clutch C-1.

The aforementioned oil passage e1, the check valve 53 and the orifice 63 is disposed, when supplying the engagement pressure P _C3 to the hydraulic servo 43 of the clutch C3 closes the check valve 53, the orifice 63 only gently supply the hydraulic pressure via and adapted rapidly discharge the oil pressure as compared with the case when discharging the engagement pressure P _C3 from the hydraulic servo 43 to supply by opening the check valve 53 ing. Moreover, the engagement pressure _{P C3} supplied to the oil path e1 is input via the oil passage e2 to the oil chamber 33a of the C3 damper 33, by the C3 damper 33, it is supplied to and discharged from the hydraulic servo 43 It prevents pulsation of Rukakarigo圧P _C3, and absorbs a surge pressure (a sharp fluctuating pressure), for example.

[Operation at 4th forward speed]
Next, for example, when the control unit 70 determines the fourth forward speed from the state of the third forward speed, the solenoid valve S1 is similarly turned on and the solenoid valve S2 is turned on by an electrical command from the control unit 70. While the pressure regulation state of the linear solenoid valve SLC1 is maintained in the OFF state, the linear solenoid valve SLC3 is closed while being turned off, and the pressure regulation control of the linear solenoid valve SLC2 is performed.

That is, first, the release control of the clutch C-3 is performed by the pressure regulation control of the linear solenoid valve SLC3, that is, the engagement pressure P _C3 (control pressure P _SLC3 ) of the hydraulic servo 43 of the clutch C-3 _passes through the oil passage e1. Through the drain port EX of the linear solenoid valve SLC3, and the clutch C-3 is released. Also, one of the linear solenoid valve SLC2 is, ON (energized) by the control pressure _{P SLC2} is 0 pressure regulation control from the state which has been closed so that the pressure is performed, the control pressure _{P SLC2} engagement pressure _{P C2} Is output from the output port SLC2b and input to the input port 22f of the second clutch apply relay valve 22 via the oil passage c1.

The second clutch apply relay valve 22 as described above, the signal pressure P _S1 solenoid valve S1 is ON has not been input to the oil chamber 22a, and the engagement pressure P _C1 that is input to the oil chamber 22b Since the left half position is locked, the control pressure P _SLC2 (engagement pressure P _C2 ) input to the input port 22f is output as the engagement pressure P _C2 from the output port 22g. Engagement pressure _{P C2} output from the output port 22g is input via the oil passage c2 to the input port 23b of the C2 relay valve 23.

Further, in the C-2 relay valve 23, the solenoid valve S2 is turned OFF, the B-2 relay valve 24 is set to the left half position, the oil chamber 23a and the oil passage h5 are in the drain state, and the biasing force of the spring 23s because it is in the left half position by the engagement pressure P _C2 input to the input port 23b is output from the output port 23c, it is also output from the output port 23e. Engagement pressure P _C2 output from the output port 23c is input to the oil chamber 21d of the first clutch apply relay valve 21 via the oil passage c5, engaging the spool 21p of the first clutch apply relay valve 21 The combined pressure P _C2 is combined with the urging force of the spring 21s to switch to the left half position and lock. At this time, the forward range pressure P _D via the oil path k1 is input to the input port 22e is switched from the output port 21i to output port 21j, but is output as a second preliminary hydraulic pressure P _DC2 to the oil passage j The second clutch apply relay valve 22 is shut off by the input port 22h. Further, since the first preliminary hydraulic pressure P _DC1 (forward range pressure P _D ) supplied to the oil passage k1 is shut off, the forward range pressure P _D as a lock pressure for the oil chamber 21c via the oil passages k2 and k3. The supply of is canceled.

Note that the oil path c5 is the check valve 55 and the orifice 65 is disposed, when supplying the engagement pressure P _C2 to the oil chamber 21d of the first clutch apply relay valve 21 closes the check valve 55, gently supply hydraulic pressure only through the orifice 65, and so rapidly discharge the oil pressure in comparison with the case of supplying open the check valve 55 when discharging the engagement pressure P _C2 from the oil chamber 21d It has become.

Then, the engagement pressure _{P C2} output from the output port 23e of the C2 relay valve 23 is input to the hydraulic servo 42 via the oil passage c3, clutch C2 is engaged. Thereby, the forward fourth speed is achieved in combination with the engagement of the clutch C-1.

Further, as described above, the check valve 52 and the orifice 62 are disposed in the oil passage c2, and the engagement pressure P _{C2 is applied} to the clutch C-2 as in the case of engine braking at the first forward speed. when supplied to the hydraulic servo 42 closes the check valve 52, and slowly the hydraulic pressure is supplied only through the orifice 62, and opens the check valve 52 when discharging the engagement pressure P _C2 from the hydraulic servo 42 The hydraulic pressure is discharged more rapidly than when it is supplied. Moreover, the engagement pressure _{P C2} supplied to the oil path c2 is input via the oil passage c4 to the oil chamber 32a of the C2-B2 damper 32, by the C2-B2 damper 32, it is supplied to and discharged from the hydraulic servo 42 It prevents pulsation of Rukakarigo圧P _C2, and absorbs a surge pressure (a sharp fluctuating pressure), for example.

[Operation at 5th forward speed]
Next, for example, when the control unit 70 determines the fifth forward speed from the state of the fourth forward speed, the solenoid valve S1 is similarly turned on and the solenoid valve S2 is turned on by an electrical command from the control unit 70. While the pressure regulation state of the linear solenoid valve SLC2 is maintained in the OFF state, the linear solenoid valve SLC1 is closed while being turned off, and the pressure regulation control of the linear solenoid valve SLC3 is performed.

That is, first, the release control of the clutch C-1 is performed by the pressure regulation control of the linear solenoid valve SLC1, that is, the engagement pressure P _C1 (control pressure P _SLC1 ) of the hydraulic servo 41 of the clutch C-1 is the oil path b1, The discharge is controlled from the drain port EX of the linear solenoid valve SLC1 via b2, and the clutch C-1 is released. Further, as in the case of the third forward speed, one linear solenoid valve SLC3 is subjected to pressure regulation control from a state in which it is _turned on (energized) and closed so that the control pressure P _SLC3 becomes zero pressure. the control pressure _{P SLC3} is output from the output port SLC3b as an engagement pressure _{P C3,} and input to the hydraulic servo 43 via the oil passage e1, the clutch C3 are engaged. Thus, in combination with the engagement of the clutch C-2, the fifth forward speed is achieved.

[Operation at 6th forward speed]
For example, when the control unit 70 determines the sixth forward speed from the state of the fifth forward speed, the solenoid valve S1 is similarly turned on and the solenoid valve S2 is turned off in response to an electrical command from the control unit 70. In this state, while the pressure regulation state of the linear solenoid valve SLC2 is maintained, the linear solenoid valve SLC3 is closed (energized) and the pressure regulation control of the linear solenoid valve SLB1 is performed.

That is, first, the release control of the clutch C-3 is performed by the pressure regulation control of the linear solenoid valve SLC3, that is, the engagement pressure P _C3 (control pressure P _SLC3 ) of the hydraulic servo 43 of the clutch C-3 _passes through the oil passage e1. Through the drain port EX of the linear solenoid valve SLC3, and the clutch C-3 is released. One linear solenoid valve SLB1 is turned off (energized) from the closed state so that the control pressure _PSLB1 becomes zero, as in the case of the second forward speed, and pressure regulation control is performed. The control pressure P _SLB1 is output from the output port SLB1b as the engagement pressure P _B1 and is input to the hydraulic servo 44 via the oil passage f1, and the brake B-1 is engaged. Thereby, the forward sixth speed is achieved in combination with the engagement of the clutch C-2.

[Operation at DN]
After that, for example, the driver decelerates the vehicle, downshifts according to the vehicle speed and stops at the first forward speed, and then shifts the shift lever from the D range position to the N range position. forward range pressure output port are communicated with the drain port with is interrupted between the input port, i.e. the forward range pressure P _D is drained.

At the same time, when the shift lever sensor (not shown) detects that the shift lever is in the N range position and the control unit 70 determines the N range based on the shift lever position, first, the linear solenoid valve SLC2 and the linear range are detected. The solenoid valve SLC3 is turned on (energized), the linear solenoid valve SLB1 is turned off, and the control pressures P _SLC2 , P _SLC3 , P _SLB1 are _drained to 0 pressure (non-output state), that is, each hydraulic servo 42 , 43, 44, 45 are drained, and the clutch C-2, the clutch C-3, the brake B-1, and the brake B-2 are released. The solenoid valve S1 is maintained in an ON (energized) state, and the solenoid valve S2 is also maintained in an OFF state. That is, the signal pressures P _S1 and P _S2 are not output from both solenoid valves S1 and S2.

On the other hand, the linear solenoid valve SLC1, for example, has a release shock when the clutch C-1 is suddenly released, so that the control pressure P _SLC1 is gradually reduced so that the control pressure is finally reduced. By draining P _SLC1 to 0 pressure (non-output state), the clutch C-1 is gently released. When the clutch C-1 is also released, all the clutches and brakes of the automatic transmission 3 are released and the neutral state is established.

  During the release control by the linear solenoid valve SLC1, the accumulator 30 connected to the input port SLC1a of the linear solenoid valve SLC1 via the oil passage a3 or the like is connected to the oil passage a1 on the linear solenoid valve SLC1 side from the orifice 60. , A3, the hydraulic pressure accumulated during the D range is released and the pressure is maintained, so that the release control of the clutch C-1 by the linear solenoid valve SLC1 is enabled. The release shock is prevented from occurring during the DN shift operation from the high speed state.

[Operation at the first reverse speed]
For example, when the shift lever is moved to the R range position by operating the shift lever of the driver, the reverse range pressure P _REV is output from the reverse range pressure output port of the manual shift valve as described above, and the reverse range pressure P _REV is input to the input port 24d of the B-2 relay valve 24 via the oil passage l and the like.

At the same time, when the shift lever sensor (not shown) detects that the shift lever is in the R range position and the control unit 70 determines the R range as the shift lever position, the solenoid valve S1 is turned on (energized). The solenoid valve S2 is maintained in the OFF state, that is, the signal pressure _PS2 is not output, so that the B-2 relay valve 24 is maintained in the left half position by the urging force of the spring 24s. The Thus, the reverse range pressure _{P REV} input to the input port 24d, an output port 24 g, is supplied to the hydraulic servo 45 of the brake B-2 via the oil passage n, the brake B-2 is engaged.

Furthermore, the linear solenoid valve SLC3 is gradually control the regulation control to output a control pressure _{P SLC3} by the control unit 70, is output from the output port SLC3b as an engagement pressure _{P C3,} the hydraulic servo 43 via the oil path e1 That is, the clutch C-3 is gently engaged. Thus, in combination with the locking of the brake B-2, the first reverse speed is achieved.

When the R range is switched to the N range, the state is the same as the state of the N range, that is, the engagement pressure P _B2 of the hydraulic servo 45 of the brake B-2 is the oil path n, B-2 relay valve 24. , the oil passage l, via the manual shift valve is drained, the engagement pressure _{P C3} of the hydraulic servo 43 of the clutch C3 is drained from the linear solenoid valve SLC3.

Further, for example, when the driver operates the shift lever to the R range position, if it is detected that the vehicle speed is equal to or higher than a predetermined speed in the forward direction, the control unit 70 turns on the solenoid valve S2, and the linear solenoid valve. maintained SLC3 the oN (energized state), that is with R range pressure _{P REV} is blocked by B-2 relay valve 24 so as not to be supplied to the hydraulic servo 45 of the brake B-2, the clutch C-3 of the hydraulic servo 43 Thus, a so-called reverse inhibit function is performed in which the engagement pressure P _C3 (control pressure P _SLC3 ) is not supplied to the _vehicle , thereby preventing the first reverse speed from being achieved.

[Operation during solenoid all-off failure]
Next, the operation of the hydraulic control device 6 during solenoid all-off failure will be described. During normal driving with the shift lever position set to the D range, all solenoid valves (linear solenoid valves SLC1, SLC2, SLC3, SLB1, solenoid valve S1) due to, for example, down, short circuit, disconnection, etc. of the control unit 70 , S2) is OFF-failed (hereinafter referred to as “all-off-fail”), the linear solenoid valve SLC1, the linear solenoid valve SLB1, and the solenoid valve S2 are normally closed types and do not output hydraulic pressure. Since the solenoid valve SLC2, the linear solenoid valve SLC3, and the solenoid valve S1 are normally open types, each hydraulic pressure is output.

During running at the forward third speed from the forward first speed in the normal state, the first clutch apply relay valve 21, the spool 21p by the first preliminary hydraulic pressure P _DC1 input to the oil chamber 21c as described above right is locked to the half position, the first preliminary hydraulic pressure P _DC1 outputted from this for the output port 21i via the oil passage k1, is input to the input port 22e of the second clutch apply relay valve 22, the left half position ( The second clutch apply relay valve 22 set to the normal position is cut off.

When an all-off failure occurs from this state, the second clutch apply relay valve 22 is in the right half position by the signal pressure _PS1 output from the solenoid valve S1 being input to the oil chamber 22a via the oil passages h1 and h3. switched to (failure time position), the first preliminary hydraulic pressure P _DC1 input to the input port 22e is output from the output port 22 d, is input to the hydraulic servo 41 via the oil passage b2, the clutch C-1 Are engaged. Further, P _SLC2 (engagement pressure P _C2 ) output from the normally open linear solenoid valve SLC2 is blocked by the input port 22f of the second clutch apply relay valve 22 switched to the right half position. On the other hand, the linear solenoid valve SLC3 is normally open, is input to the input port SLC3a the line pressure _{P L} as a substantially intact engagement pressure _{P C3,} is output from the output port SLC3b, the hydraulic servo via the oil passage e1 43 The clutch C-3 is engaged. Thereby, the clutch C-1 and the clutch C-3 are engaged to achieve the third forward speed (see FIG. 3), that is, all-off fail when traveling from the first forward speed to the third forward speed. In this case, the traveling state by the third forward speed is ensured.

Further, when the vehicle travels from the fourth forward speed to the sixth forward speed during normal operation, the control pressure P _SLC2 (engagement pressure P _C2 ) of the clutch C-2 is the oil path c1 and the second clutch apply relay as described above. The oil is input to the oil chamber 21d of the first clutch apply relay valve 21 through the valve 22, the oil passage c2, the C-2 relay valve 23, and the oil passage c5, and the spools 21p and 21q are locked in the left half position. Therefore, the second preliminary oil pressure P _DC2 outputted from the output port 21j, via the oil path j, is input to the input port 22h of the second clutch apply relay valve 22, the second clutch apply relay valve is in the left half position 22 is a state of being blocked.

When an all-off failure occurs from this state, the second clutch apply relay valve 22 is in the right half position by the signal pressure _PS1 output from the solenoid valve S1 being input to the oil chamber 22a via the oil passages h1 and h3. In addition, the solenoid valve S2 is turned OFF and the B-2 relay valve 24 is maintained in the left half position without being switched, so that the oil passage h4 is shut off and the solenoid passage S1 is connected to the oil passage h5. Since the signal pressure _PS1 is not output, the C-2 relay valve 23 is not switched and is maintained in the left half position. Therefore, the second preliminary hydraulic pressure _{P DC2} input to the input port 22h of the second clutch apply relay valve 22 is output from the output port 22 g, the oil passage c2, C-2 relay valve 23 via the oil passage c3 Input to the hydraulic servo 42 causes the clutch C-2 to be engaged. Further, P _SLC2 (engagement pressure P _C2 ) output from the normally open linear solenoid valve SLC2 is blocked by the input port 22f of the second clutch apply relay valve 22 switched to the right half position. The second preliminary hydraulic pressure _PDC2 output to the oil passage c2 is also output to the oil passage c5 via the C-2 relay valve 23 and is input to the oil chamber 21d of the first clutch apply relay valve 21, so that the first The 1-clutch apply relay valve 21 is continuously locked in the left half position. Then, the linear solenoid valve SLC3 is normally open, is input to the input port SLC3a the line pressure _{P L} as a substantially intact engagement pressure _{P C3,} is output from the output port SLC3b, the hydraulic servo 43 via the oil path e1 The clutch C-3 is engaged. As a result, the clutch C-2 and the clutch C-3 are engaged to achieve the fifth forward speed (see FIG. 3), that is, all-off failure when traveling from the fourth forward speed to the sixth forward speed. In this case, the traveling state by the fifth forward speed is ensured.

In the case of an all-off failure during normal driving from the fourth forward speed to the sixth forward speed, once the vehicle is stopped and the shift lever is set to the N range position, the manual shift valve (not shown) drain outputs stop forward range pressure P _D, is the forward range pressure P _D is drained particularly for the linear solenoid valve SLC2 is a normally open input port 21e of the first clutch apply relay valve 21. Then, the second preliminary hydraulic pressure _PDC2 input to the oil chamber 21d input via the oil passages j, c2, and c5 is drained, and the lock by the second preliminary hydraulic pressure _PDC2 is released. Further, since the signal pressure P _S1 is continuously output from the normally open solenoid valve S1, the spools 21p and 21q of the first clutch apply relay valve 21 are moved to the right half by the signal pressure P _S1 input to the oil chamber 21a. Switched to position.

In the state of the N range at the time of this all-off failure, the line pressure P _L is used as the original pressure, and the control pressure P _SLC3 (engaged from the linear solenoid valve SLC3 that is normally open is substantially the same as the line pressure P _L. Since the pressure P _C3 ) is output, the clutch C-3 is in the engaged state. Even if the clutch C-3 is engaged, the clutches C-1 and C-2 and the brakes B-1 and B-2 are in the released state, and even if the decelerated rotation is input to the sun gear S2, the sun gear S3 Since the carrier CR2 is idled, the input shaft 10 and the counter gear 11 are substantially in a neutral state (see FIG. 2).

Then, for example, again the shift lever by the driver is in the D range position, the forward range pressure P _D from the manual shift valve is output, the forward range pressure P _D is the first clutch apply that switched to the right half position is input to the input port 21e of the relay valve 21 is output from the output port 21i to the oil passage k1 as the first preliminary oil pressure _{P DC1,} the input port 22e of the second clutch apply relay valve 22 to the right half position, the output port 22d, input to the hydraulic servo 41 of the clutch C-1 via the oil passage b2, and the clutch C-1 is engaged, that is, all-off failure when traveling from the first forward speed to the third forward speed. It becomes the same state as the hour, and the third forward speed is secured. As a result, the vehicle can be restarted even after the vehicle has stopped after the all-off failure, and the limp home function is ensured.

As described above, according to the hydraulic control device 6, during normal traveling, the clutches C-1, C-2, C-3 are respectively connected by the control pressures P _SLC1 , P _SLC2 , P _SLC3 by the linear solenoid valves SLC1, SLC2, SLC3. The control pressure P _SLC3 of the linear solenoid valve SLC3 is supplied to the hydraulic servo 43 of the clutch C-3 and the clutch C-2 is engaged by the first clutch apply relay valve 21 during all-off failure. The output state of the first or second preliminary hydraulic pressure P _DC1 , P _DC2 is switched based on the state, and the first or second preliminary hydraulic pressure P _DC1 , P _{DC2 is changed} to the hydraulic pressure of the clutch C-1 by the second clutch apply relay valve 22. It is possible to supply the servo 41 or the hydraulic servo 42 of the clutch C-2 respectively. That. Thus, when an all-off failure occurs during traveling, the first clutch apply relay valve 21 achieves the third forward speed or the fifth forward speed according to the gear position before the all-off failure occurs. And the second clutch apply relay valve 22 can be achieved with only two valves, which can reduce the size and cost.

Incidentally, in the sixth forward speed from the normal state of the fourth forward speed as described above, the control pressure _{P SLC2} of the linear solenoid valve SLC2 is supplied as the engagement pressure _{P C2} to the hydraulic servo 42 of the clutch C2 And is supplied to the oil chamber 21d of the first clutch apply relay valve 21, and the spools 21p, 21q of the first clutch apply relay valve 21 are switched to the left half position.

For example, when the linear solenoid valve SLC2 is configured as a normally closed type and an all-off failure occurs from the fourth forward speed to the sixth forward speed, the output port SLC2b of the linear solenoid valve SLC2 is closed and the control pressure P _SLC2 is reduced. It becomes 0 pressure. On the other hand, the signal pressure _PS1 is output from the solenoid valve S1 configured as a normally open type, and is input to the oil chamber 21a of the first clutch apply relay valve 21.

From this time, since the signal pressure P _S1 of the solenoid valve S1 is also input to the oil chamber 22a of the second clutch apply relay valve 22, for example, the second clutch apply relay valve 22 is switched to the first clutch apply relay valve 21 If it is first switched to the right half position, the second preliminary hydraulic pressure _PDC2 supplied to the oil passage j is supplied to the hydraulic servo 42 of the clutch C-2 via the oil passages c2 and c3, and the oil passage Since the oil is supplied to the oil chamber 21d of the first clutch apply relay valve 21 through c5, the first clutch apply relay valve 21 is maintained at the left half position (high speed side position) and moves forward as described above. There is no problem because the fifth gear is achieved.

However, for example, switching of the second clutch apply relay valve 22 is delayed than the switching of the first clutch apply relay valve 21, the control pressure P _SLC2 of the oil chamber 21d of the first clutch apply relay valve 21 becomes 0 pressure and with results, since the signal pressure P _S1 of the solenoid valve S1 to the oil chamber 21a from being entered, the first clutch apply relay valve 21 will be switched to the right half position (low speed stage side position), as described above In this case, the third forward speed may be formed and a downshift may occur.

Therefore, in the hydraulic control device 6, the linear solenoid valve SLC2 is configured as a normally open type, so even if an all-off failure occurs from the fourth forward speed to the sixth forward speed, the output port SLC2b of the linear solenoid valve SLC2 opens, the control for pressure P _SLC2 is output equivalent to approximately the forward range pressure P _D, that is, the control pressure P _SLC2 input to the oil chamber 21d of the first clutch apply relay valve 21 does not decrease, the oil chamber be the signal pressure _{P S1} of the solenoid valve S1 is input to the 21a, exceeded and the biasing force of the control pressure _{P SLC2} and the spring 21s of the oil chamber 21d, the first clutch apply relay valve 21 left half position (high speed stage Side position) and prevent malfunctions that can be switched to the right half position (low speed stage position). It can be.

Further, the first clutch apply relay valve 21 inputs the forward range pressure P _D (first preliminary hydraulic pressure P _DC1 ) that has passed through the valve in the right half position (low speed side position) to the oil chamber 21c. which is configured, is locked in the right half position, and is configured to be able to maintain the right half position also the control pressure P _SLC1 of the linear solenoid valve SLC1 decreases due to e.g. pressure regulating operation, and the like. For this reason, for example, if the linear solenoid valve SLC2 is configured normally closed, the control pressure P _SLC2 decreases and the first clutch apply is applied when an all-off failure occurs from the fourth forward speed to the sixth forward speed. When the spool 21p of the relay valve 21 will move even slightly toward the right half position, it causes the lock action of the forward range pressure P _D of the oil chamber 21c occurs, erroneous results is switched further to the right half position operation May occur easily.

However, in the hydraulic control apparatus 6, since the linear solenoid valve SLC2 is configured as a normally open type as described above, the control pressure P _SLC2 supplied to the oil chamber 21d is prevented from being lowered, so that The first clutch apply relay valve 21 can be maintained at the left half position (high speed stage position).

  Next, after shifting to the gear stage by the solenoid all-off failure (in this embodiment, the third forward speed) at the time of determination (detection) of the low voltage state, which is a feature of the present invention, the all-off fail state is stepwise. FIG. 5 to FIG. 8 are referred to for details of the automatic transmission control device 1 that can perform a shift at the time of detecting a low voltage state smoothly and reliably without a shift shock by performing a control to shift to the same state as in FIG. To explain.

  That is, as shown in FIG. 5, when an unillustrated ignition switch is turned on (energized) by the driver, the voltage detection sensor 77 checks the voltage of the battery 75 to determine whether or not a low voltage state has occurred ( Detection) (step S1). This determination is performed by sampling whether or not the voltage Vo of the battery 75 is less than a constant voltage α (for example, 9 [V]) (Vo <α [V]) every predetermined time (for example, several seconds). When the state of Vo <α [V] is continuously detected for a certain period (for example, 1 second), the low voltage failure determination control means 71 increments the low voltage failure detection counter 76 by +1. As a result, if the low voltage state is not determined in step S1, the process proceeds to step S2 to determine whether or not the ignition switch is turned off (non-energized). If not, the judgment in step S1 is repeated and turned off. When it is determined that the processing has been completed, the process is terminated.

  On the other hand, when the low voltage state is determined (detected) by the voltage detection sensor 77 in step S1, the process proceeds to step S3, and fail safe control is executed. In the fail-safe control, as shown in the flowchart of the subroutine in FIG. 6, when the process starting with the label “low voltage state detection” is started, the low voltage failure confirmation control means 71 detects that the low voltage state is detected. The process proceeds so that the occurrence of a low voltage failure is confirmed when it continues for a predetermined time (for example, 20 seconds). That is, in step S11, the low voltage failure determination control means 71 uses the simultaneous engagement avoidance control means 72 to determine whether the gear stage (shift stage) when the low voltage state is detected is within the third forward speed (<= 3rd). Is determined based on the signal from the shift determining means 74, and if it is determined that the speed is within the third forward speed, the process proceeds to step S12, and the third forward speed (to be shifted at the time of solenoid all-off failure) Shift to 3rd).

For example, when a low voltage state is detected during traveling from the first forward speed to the third forward speed during normal operation, the first clutch apply relay valve 21 is locked at the right half position as described above. the first preliminary hydraulic pressure P _DC1 output from the output port 21i, via the oil passage k1, is input to the input port 22e of the second clutch apply relay valve 22, a second, which is the left half position (normal position) The clutch apply relay valve 22 is in a state of being cut off. In this state, the second clutch apply relay valve 22 tries to switch to the right half position when the signal pressure _PS1 output from the solenoid valve S1 is input to the oil chamber 22a. Since the solenoid valve SLC1 is maintained in the ON (energized) state, the second clutch apply relay valve 22 receives the control pressure P _SLC1 input to the input port 22c to the oil chamber 22b, and the spool 22p The control pressure P _SLC1 to 22b and the _urging force of the spring 22s overcome the signal pressure _PS1 input to the oil chamber 22a and are held at the left half position, and are in a state of being locked at the left half position. . As a result, the control pressure P _SLC1 is maintained in a state of being input from the input port 22c to the hydraulic servo 41 via the output port 22d and the oil passage b2, and the engagement of the clutch C-1 is maintained.

Furthermore, the simultaneous engagement avoidance control means 72, for switching the linear solenoid valve SLC3 is normally open to OFF, the linear solenoid valve SLC3 is input to the input port SLC3a the line pressure _{P L} substantially as the engagement pressure output as P _C3, and input to the hydraulic servo 43 via the oil path e1, to engage the clutch C3. That is, (see S1 in FIG. 5, FIG. 7) voltage detection when the sensor 77 detects a low voltage fault at time t _1, in order to shift to the third forward speed to be migrated during all-off failure, as shown by the graph A In the state where the linear solenoid valve SLC1 is turned on (energized), the command hydraulic pressure for gradually increasing the pressure after controlling the pressure by regulating the linear solenoid valve SLC3 as shown in the graph B. Is output.

  The hydraulic pressure to the hydraulic servo 42 of the clutch C-2, which is OFF when traveling from the first forward speed to the third forward speed, is maintained by keeping the linear solenoid valve SLC2 in the OFF state. Blocked as indicated by C. Further, when a low voltage failure occurs in the second forward speed at normal time, the simultaneous engagement avoidance control means 72 switches the linear solenoid valve SLB1 to OFF (non-energized) so that the hydraulic pressure is input to the hydraulic servo 44. Shut off and release the engaged brake B-1.

As a result, the actual hydraulic pressure applied to the clutch C-1 is maintained at a constant value as shown in the graph D, and the actual hydraulic pressure applied to the clutch C-3 gradually increases after so-called looseness as shown in the graph E. As a result, the actual hydraulic pressure of the clutch C-1 is changed to be approximately equal to the actual hydraulic pressure, and the clutch C-3 is engaged together with the clutch C-1 to form the third forward speed. At this time, the actual hydraulic pressure to the clutch C-2 does not increase as shown by the graph F, and therefore the clutch C-2 is not engaged. That is, when the low voltage state is detected as described above during traveling from the first forward speed to the third forward speed during normal operation, the first clutch apply relay valve 21 is input to the oil chamber 21c at this time. spool 21p by the first preliminary hydraulic pressure P _DC1 that is that is locked in the right half position, output the first preliminary oil pressure P _DC1 output from the port 21i is, the second clutch apply relay valve 22 via the oil path k1 Is input to the input port 22e, but is blocked by the second clutch apply relay valve 22 in the left half position.

Furthermore, the simultaneous engagement avoidance control means 72 in this state, the solenoid valve S1 is OFF (S13 in FIG. 6, the point of FIG. 7 t _2), then determines whether switching of the solenoid valve S1 is completed (S14) If it is determined that the process is not ended, step S14 is repeated, and when it is determined that the process is ended, the process proceeds to step S15. That is, in the time t ₂ before the clutch C-3 is fully engaged, since the normally open type solenoid valve S1 is controlled in simultaneous engagement avoidance control means 72 is turned OFF, the modulator pressure P _MOD from the output port S1b Is output as the signal pressure _PS1 as it is through the oil passages h1 and h3. Thus, the second clutch apply relay valve 22, the signal pressure P _S1 from the solenoid valve S1 is input to the oil chamber 22a is about to be switched to the right half position, as described above, the second clutch apply relay In the valve 22, the spool 22p overcomes the signal pressure _PS1 by the control pressure _{PSLC1 applied} to the oil chamber 22b and the _urging force of the spring 22s, is held at the left half position, and stands by in a locked state at the left half position. Therefore, the clutch C-1 _receives the control pressure (first hydraulic pressure) _PSLC1 from the hydraulic servo 41 and maintains the engaged state. Whether or not the switching of the solenoid valve S1 in step S14 has been completed is determined using a timer (not shown).

Further, in this state, the simultaneous engagement avoidance control means 72 turns OFF the linear solenoid valve SLC1 the (de-energized) is switched to the state output by the OFF (S15 in FIG. 5, the time _t 3 in FIG. 7), gear After the stage (gear stage) is fixed at the third forward speed (S16), the process proceeds to step S19. That is, by the linear solenoid valve SLC1 is turned OFF at time _{t 3,} the second clutch apply relay valve 22, since the control pressure _{P SLC1} which has been input via the oil path b5 to the oil chamber 22b is shut off, The spool 22p that has been urged only by the spring 22s is quickly switched to the right half position by defeating the signal pressure _PS1 to the oil chamber 22a. Therefore, it until the clutch C-1 which has been inputted to the control pressure _{P SLC1} to the hydraulic servo 41 maintains the engaged state, the first preliminary hydraulic pressure _{P DC1} is supplied to the input port 22e, the control pressure _{P SLC1} Instead, the engagement state can be continuously maintained by smoothly inputting the hydraulic servo 41 in a natural manner. Accordingly, by turning OFF the solenoid valve S1 and the linear solenoid valve SLC1 in this order, the second clutch apply relay valve 22 is switched to replace the control pressure P _{SLC1 with} the input of the first preliminary hydraulic pressure P _DC1 that is the forward range pressure. Thus, the hydraulic pressure input to the hydraulic servo 42 of the clutch C-2 can be reliably cut off. As a result, the forward third speed is achieved by engaging the clutch C-1 and the clutch C-3 in a form free from a shift shock while reliably preventing the occurrence of a problem such that the clutch C-2 engages and ties up. A stage can be achieved. By the linear solenoid valve SLC1 in the time _{t 3} has been turned OFF, the hydraulic pressure command to the linear solenoid valve SLC1 (command oil pressure) is reduced once, the first preliminary hydraulic pressure in place of the control pressure _{P SLC1} as described above Since _PDC1 is input to the hydraulic servo 41, the actual hydraulic pressure to the clutch C-3 does not change, and the third forward speed is stably achieved (see the dot-dash line circle G). In this way, the simultaneous engagement avoidance control means 72 mainly controls the first clutch apply relay valve 21, the second clutch apply relay valve 22, and the solenoid valve S1 until the low voltage failure occurrence is determined and determined. Control is performed so as to avoid simultaneous engagement of the clutches C-1, C-2, and C-3 while the low voltage state is continued.

On the other hand, if the simultaneous engagement avoidance control means 72 determines in step S11 that the gear stage at the time of detecting the low voltage failure is not within the third forward speed, the process proceeds to step S17 and the fifth forward speed (5th) ). In other words, when a low voltage state is detected during traveling from the fourth forward speed to the sixth forward speed, the control pressure P _SLC2 of the clutch C-2 is determined when it is determined that it is not within the third forward speed. The clutch C-2 is engaged when the combined pressure P _C2 ) is input to the hydraulic servo 42, and control is performed to maintain this engaged state. Then, in a low voltage fault detection when the gear stage is the fourth forward speed, for example of the second clutch apply relay valve 22 in a state that was in the left half position first preliminary oil pressure P _DC1 and the second preliminary oil pressure P _DC2 In a state where both are shut off, the linear solenoid valve SLC1 is switched to the OFF state, the control pressure P _SLC1 is stopped, and the clutch C-1 is released. When the gear stage at the time of failure detection is the sixth forward speed stage, the linear solenoid valve SLB1 is turned off to stop the control pressure _PSLB1 and release the brake B-1. If the gear position at the time of failure detection is the fifth forward speed, control is performed so that the engaged state of the clutch C-2 and the clutch C-3 is maintained as it is.

From the above state, the control pressure P _SLC2 is input to the input port 22f of the second clutch apply relay valve 22 in the left half position by the pressure regulation control of the linear solenoid valve SLC2, and the oil is output from the output port 22g. The clutch C-2 is engaged by being input to the hydraulic servo 43 through the path c2, the input port 23b, the output port 23e of the C-2 relay valve 23 in the left half position, and the oil path c3. In this manner, the fifth forward speed (5th) achieved by engagement of the clutch C-2 and the clutch C-3 is fixed (S18), and the process proceeds to step S19.

  In step S19, the low voltage failure determination control means 71 determines whether or not the normal determination condition is satisfied. If it is determined that the normal determination condition is not satisfied, the process proceeds to step S20 to determine whether or not the failure determination condition is satisfied. Determine whether. As described above, the normal determination condition is a condition for determining that the battery 75 has returned to a normal state when it is detected that a constant voltage (for example, 10 [V]) has continued for a certain period of time (for example, 1 second). It is. Further, the low voltage failure confirmation condition is for determining the occurrence of the low voltage failure when the low voltage failure detection counter 76 continuously counts 20 times (measures for 20 seconds), for example. As a result, while the failure confirmation condition is not satisfied, steps S19 and S20 are repeated, and when it is determined that the failure confirmation condition is satisfied, the process proceeds to step S21, the occurrence of the low voltage failure is confirmed, and the emergency mode is entered. . In step S21, the emergency control means 78 performs solenoid all-off fail control, and controls the above-mentioned fail-safe mechanism when the occurrence of the low voltage failure is determined by the low voltage failure confirmation control means 71. Thus, the control for forming the third forward speed is continued as a solenoid all-off failure.

  The solenoid all-off failure, as described above, turns off all the linear solenoid valves SLC1, SLC2, SLC3, SLB1, and the solenoid valves S1, S2. When the speed is from the first forward speed to the third forward speed, the traveling state by the third forward speed is ensured, and when the low voltage failure is detected, the gear stage is from the fourth forward speed to the sixth forward speed. Is controlled so as to ensure the traveling state by the fifth forward speed. Note that the fact that the low voltage failure has been determined in step S21 is written in a ROM (not shown) in the control unit 70.

When the normal determination condition is satisfied in step S19, that is, when it is detected that a constant voltage (for example, 10 [V]) continues for a certain time (for example, 1 second), the return control means 73 When it is determined by the simultaneous engagement avoidance control means 72 that the normal determination condition is established that the voltage of the battery 75 has continued for a predetermined time after being fixed at the third forward speed using the fail-safe mechanism. In addition, after the linear solenoid valve SLC1 is switched to the energized state and the solenoid valve S1 is further switched to the energized state, the return control is performed to shift to the normal control that can shift gears other than the third forward speed. That is, the return control means 73 turns on the linear solenoid valve SLC1 that has been turned off in step S22 and outputs the control pressure P _SLC1, and then _turns on the solenoid valve S1 that has been turned off in step S23. It is determined whether or not the solenoid valve S1 has been turned on. As a result, when it is determined that the ON switching of the solenoid valve S1 has been completed, the routine proceeds to step S25, shifts to normal control that can shift to another gear, and returns.

  Then, after completing step S21 or step S25, the process proceeds to step S4 in FIG. 5 to determine whether or not the ignition switch has been turned off. When it is determined that the ignition switch has been turned off, the process ends.

By the way, when the control according to the present invention as described above is not performed, a comparative example shown in FIG. 8 is obtained. That is, when the low voltage state is detected at time t ₁ of the drawing, switch to the first preliminary oil pressure P _DC1 by the forward range pressure input to the hydraulic servo 41 as in this embodiment from the control pressure P _SLC1 If control is not performed and the control pressure P _SLC1 is simply used to switch to the third forward speed, the result is as follows. That is, the linear solenoid valve SLC1 is turned on (energized) as shown in the graph A in the figure, and the linear solenoid valve SLC3 is turned on and the pressure is controlled as shown in the graph B, and then gradually adjusted so-called looseness. If the command hydraulic pressure is output so as to be increased and the linear solenoid valve SLC2 is kept OFF as shown in the graph C, the actual hydraulic pressure to the clutch C-1 is constant until a certain time as shown in the graph D. The actual hydraulic pressure applied to the clutch C-3 is gradually increased after so-called looseness and changed so as to be equal to the actual hydraulic pressure of the clutch C-1. 1 and the clutch C-3 are engaged to form the third forward speed. However, the actual hydraulic pressure to the clutch C-2 is, from the state of the code F ₁ in the normal state, gradually increases as F ₂ with a low voltage failure, also the actual hydraulic pressure to the clutch C-1, normal From the state of the reference sign E ₁ , the pressure gradually decreases as indicated by E ₂ due to a low voltage failure, and as indicated by a dashed line circle H, the actual hydraulic pressure to the clutch C- 1 decreases and the clutch C- The clutch C-2, which is a friction engagement element other than 1 and C-3, is engaged, and simultaneous engagement (tie-up) of the three elements occurs.

  As described above, according to the present embodiment, the simultaneous engagement avoidance control means 72 shifts to the third forward speed and is controlled by the first clutch apply relay valve 21, the first speed during the control by the low voltage failure confirmation control means 71. By controlling the fail-safe mechanism comprising the two-clutch apply relay valve 22 and the solenoid valve S1, the clutches C-1, C-2, C- while the low voltage state continues until the low voltage failure occurrence is determined and determined 3 simultaneous engagement is avoided. For this reason, there are only a few switching valves arranged in the oil passage for fail-safe operation, while having a simple circuit configuration that eliminates the switching valve for restricting simultaneous engagement of clutches that should not be engaged as much as possible. The first clutch apply relay valve 21 and the second clutch apply relay valve 22 are controlled so as to avoid simultaneous engagement after shifting to the third forward speed until it is determined that the low voltage failure has occurred. be able to. Therefore, when a low voltage failure occurs, the third forward speed can be maintained while reliably preventing the hydraulic pressure supply to the clutch C-2 that should not be engaged in the third forward speed.

Further, according to the present embodiment, the simultaneous engagement avoidance control means 72 de-energizes the second clutch apply relay valve 22 and the solenoid valve S1 that are continuously supplied with the control pressure P _SLC1 after shifting to the third forward speed. By switching to the state, the linear solenoid is made to stand by in a state where it can be switched to the position at the time of failure (right half position in FIG. 4) for supplying the first preliminary hydraulic pressure _PDC1 to the hydraulic servo 41 instead of the control pressure P _SLC1 . By switching the valve SLC1 to the non-energized state and shutting off the supply of the control pressure P _SLC1 , the supply oil passage for the control pressure P _SLC2 to the hydraulic servo 42 is shut off, and the first preliminary hydraulic pressure P _DC1 is supplied to the hydraulic servo 41. Clutch C that receives the control pressure P _SLC3 is input to the hydraulic servo 43 by the pressure regulation operation of the linear solenoid valve SLC3. -3 is fixed to the third forward speed. For this reason, the solenoid valve S1 and the linear solenoid valve SLC1 are in the non-energized state in this order, while having a simple circuit configuration in which the switching valves other than the linear solenoid valves SLC1, SLC2, SLC3 and the solenoid valve S1 are eliminated as much as possible. Switching and the switching operation of the first clutch apply relay valve 21 and the second clutch apply relay valve 22 to prevent the supply of hydraulic pressure to the clutch C-2 that should not be engaged in the event of a low voltage failure, The third forward speed can be maintained without shock.

  Further, in the present embodiment, the low voltage failure confirmation control means 71 includes the return control means 73. Therefore, when the low voltage state of the battery 75 is recovered, the normal voltage control is quickly returned to the normal running according to the situation. be able to. Further, the emergency control means 78 controls the fail-safe mechanism when the low-voltage failure confirmation control means 71 confirms the occurrence of the low-voltage failure, thereby controlling the formation of the third forward speed by the solenoid. Since it is continuously performed as an all-off failure, when it is determined that a low-voltage failure has occurred, it is possible to shift to the solenoid-all-off failure mode by continuing the already established third forward speed as it is. .

  In the embodiment described above, the case where the control device 1 of the automatic transmission is applied to the automatic transmission 3 that achieves the sixth forward speed and the first reverse speed has been described as an example. For example, the present invention may be applied to an automatic transmission that achieves eight forward speeds. The present invention is applicable to any automatic transmission as long as it is an automatic transmission that performs a stepped shift. can do.

  The automatic transmission control apparatus according to the present invention is suitable for use in passenger cars, trucks, buses, agricultural machines, and the like.

DESCRIPTION OF SYMBOLS 1 Control apparatus of automatic transmission 3 Automatic transmission 21 Preliminary gear stage switching valve, fail safe mechanism (first clutch apply relay valve)
22 Hydraulic supply switching valve, fail-safe mechanism (second clutch apply relay valve)
41 1st hydraulic servo (hydraulic servo)
42 Second hydraulic servo (hydraulic servo)
43 3rd hydraulic servo (hydraulic servo)
71 Low voltage failure determination control means 72 Simultaneous engagement avoidance control means 73 Return control means 75 Battery 77 Low voltage state detection unit (voltage detection sensor)
78 Fail-safe control means (emergency control means)
c2 Supply oil passage (oil passage)
C-1 First friction engagement element (clutch)
C-2 Second frictional engagement element (clutch)
C-3 Third friction engagement element (clutch)
P _DC1 first preliminary hydraulic pressure P _DC2 second preliminary hydraulic pressure P _SLC1 first hydraulic pressure (control pressure)
P _SLC2 second hydraulic pressure (control pressure)
P _SLC3 3rd hydraulic pressure (control pressure)
_PS1 4th hydraulic pressure (signal pressure)
SLC1 1st solenoid valve (linear solenoid valve)
SLC2 2nd solenoid valve (linear solenoid valve)
SLC3 3rd solenoid valve (linear solenoid valve)
S1 4th solenoid valve, fail-safe mechanism (solenoid valve)

Claims (4)

First, second and third frictional engagement elements that do not engage at the same time during normal operation;
A normally closed type first solenoid valve capable of supplying a first hydraulic pressure to the first hydraulic servo of the first friction engagement element when energized;
A normally open type second solenoid valve capable of supplying the second hydraulic pressure to the second hydraulic servo of the second friction engagement element when de-energized;
A normally open third solenoid valve capable of supplying a third hydraulic pressure to a third hydraulic servo of the third friction engagement element when de-energized;
A fail-safe mechanism for engaging the first and third friction engagement elements at the time of solenoid all-off failure to enable formation of a predetermined shift stage;
A low voltage state detector that detects a low voltage state of a battery that supplies power to at least the first to third solenoid valves;
An automatic shift comprising: a low voltage failure determination control means for determining that a low voltage failure has occurred when the low voltage state is detected by the low voltage state detection unit and the low voltage state continues for a predetermined time; In the control device of the machine,
During the control by the low-voltage failure confirmation control means, the low-voltage state is continued until the low-voltage failure occurrence is confirmed by controlling the fail-safe mechanism while shifting to the predetermined shift stage. A simultaneous engagement avoidance control means for avoiding simultaneous engagement of the first, second and third friction engagement elements in
A control device for an automatic transmission. The failsafe mechanism is
A normally open type fourth solenoid valve capable of outputting the fourth hydraulic pressure when not energized;
A low-speed position for outputting a first preliminary hydraulic pressure for the first hydraulic servo in accordance with a supply state of the first hydraulic pressure and the fourth hydraulic pressure, and a second preliminary hydraulic pressure for the second hydraulic servo A high-speed stage side position that outputs a preliminary gear stage switching valve that can be switched to,
A normal position where the first and second hydraulic pressures can be supplied to the first and second hydraulic servos according to the supply states of the first hydraulic pressure and the fourth hydraulic pressure, respectively, and the low voltage state A hydraulic pressure supply switching valve that is switched to a failure position where the first preliminary hydraulic pressure can be supplied to the first hydraulic servo when the detection unit detects the low voltage state;
The simultaneous engagement avoidance control means switches the hydraulic pressure supply switching valve, which continues to be supplied with the first operating hydraulic pressure after shifting to the predetermined gear position, by switching the fourth solenoid valve to a non-energized state. The first preliminary hydraulic pressure is supplied to the first hydraulic servo in place of the first hydraulic pressure, and the first solenoid valve is switched to the non-energized state after being switched to the failure position. By shutting off the supply of the working hydraulic pressure, the supply hydraulic path for the second working hydraulic pressure to the second hydraulic servo is shut off, and the first preliminary hydraulic pressure is input to the first hydraulic servo and the first friction is applied. The engagement of the engagement element is continued, and the predetermined speed change is performed by the engagement of the third friction engagement element to which the third hydraulic pressure is input to the third hydraulic servo by the pressure regulation operation of the third solenoid valve. Fixed to the stage Made,
The control device for an automatic transmission according to claim 1. The low voltage failure determination control means determines whether the battery voltage has continued to be a predetermined voltage for a certain period of time after being fixed at the predetermined shift speed by using the fail safe mechanism by the simultaneous engagement avoidance control means. When it is determined that the condition is satisfied, the first solenoid valve is switched to the energized state, and further, the fourth solenoid valve is switched to the energized state. Comprising return control means for performing return control to shift to control,
The control apparatus for an automatic transmission according to claim 2. When the occurrence of the low voltage failure is confirmed by the low voltage failure confirmation control means, the fail safe mechanism is controlled to continuously perform the control for forming the predetermined shift stage as the solenoid all-off failure. With fail-safe control means,
The control device for an automatic transmission according to any one of claims 1 to 3.

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