JP2019002528A - Control device of electromagnetic valve drive circuit - Google Patents

Abstract

To provide an automatic transmission control device which can diagnose a failure at high performance without the necessity for detecting an energization current of an electromagnetic valve.SOLUTION: A control device 6 outputs a test block signal for diagnosing whether or not a block circuit 16 is normally blocked to the block circuit 16 (S14: test block signal output part). The control device 6 outputs, to a switching element 14c, a test control signal for turning on the switching element 14c, and satisfying a condition that a detection voltage of an electric charge accumulation node N4 is lowered to a normal prescribed value Vth if the switching element is normally operated when withdrawing an electric charge from the electric charge accumulation node N4 through a driving coil Lc of an electromagnetic valve 12c, being the test control signal for carrying electricity to the driving coil Lc of the electromagnetic valve 12c which satisfies a condition that the engagement of input/output shafts of an automatic transmission 3 is not changed (S15: test control signal output part). Then the control part diagnoses whether or not the block circuit 16 is normally blocked. (S16 to S24).SELECTED DRAWING: Figure 6

Description

  The present invention relates to a control device that drives and controls a solenoid of a solenoid valve.

  Conventionally, for example, a control device that drives and controls a solenoid of an electromagnetic valve of an automatic transmission has been provided (see, for example, Patent Document 1). The control device described in Patent Document 1 controls driving of a plurality of normally closed linear solenoid valves of a hydraulic circuit in order to form a shift stage of an automatic transmission.

  A solenoid is provided as an electromagnetic part for driving a plurality of linear solenoid valves, and a plurality of transistors are provided as switching elements for energizing the solenoids. And the interruption | blocking circuit is provided in order to perform a connection and interruption | blocking with a DC power supply and a some transistor. This cutoff circuit is configured by connecting a cutoff transistor and a cutoff sub-transistor in series. When the ignition switch is turned on, both are turned on, and when the ignition switch is turned off, both are turned off. In the technique disclosed in Patent Document 1, in order to diagnose whether or not the cutoff circuit operates normally, when the ignition switch is turned off, the cutoff transistor is instructed to be turned off and the driving transistor is switched. A command is made to diagnose whether or not the shut-off transistor is operating normally in response to detecting the energization current of the solenoid.

JP 2013-204785 A

  In the technique described in Patent Document 1, an ammeter (for example, a current detection resistor) is required to detect the energization current of the solenoid. For this reason, in order to detect a current and diagnose a fault, an ammeter must be prepared for each solenoid so that a large current can be applied. Moreover, in order to diagnose the shut-off circuit, the diagnosis must be made when the shut-off circuit may be shut off. For example, the diagnosis must be performed after the IGOFF is performed, and the diagnosis time is limited, which is convenient. The nature is bad.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an automatic transmission control device that enables failure diagnosis without detecting the energization current of a solenoid valve, and enables failure diagnosis of a shut-off circuit while suppressing restrictions on the diagnosis time. It is in.

  According to the first aspect of the present invention, the test cutoff command output unit outputs a test cutoff command for diagnosing whether or not the cutoff circuit normally shuts down to the cutoff circuit. The test control signal output unit turns on the switching element from the OFF state of the switching element, and when the charge is extracted from the charge accumulation node where charge is accumulated between the power supply node and the switching element through the driving coil of the solenoid valve. If the operation is normal, a test control signal that satisfies the condition that the detection voltage of the charge storage node is lower than the normal predetermined value is output to the switching element. This test control signal is a control signal for energizing the drive coil of the solenoid valve with a current that satisfies the condition that the engagement of the input / output shaft of the automatic transmission does not change. Then, it is possible to diagnose whether or not the cutoff circuit normally shuts down in response to the test cutoff command output unit outputting the test cutoff command and the test control signal output unit outputting the test control signal.

  Here, when a failure of the cutoff circuit is diagnosed using the voltage detected from the charge storage node where charge is stored between the power supply node and the switching element, the switching element is turned off when a test control signal is output to the switching element. At this time, the voltage of the charge storage node is discharged through the driving coil of the solenoid valve. When normal, the detection voltage of the charge storage node is lower than the normal predetermined value. At the time of abnormality, the detection voltage of the charge storage node is equal to or higher than a normal predetermined value. For this reason, it is possible to make a fault diagnosis of the cutoff circuit using the voltage detected from the charge storage node, and it is not necessary to detect the energization current to the drive coil of the solenoid valve.

  Moreover, since this test control signal is a control signal for energizing the drive coil of the solenoid valve with a current that satisfies the condition that the engagement of the input / output shaft of the automatic transmission does not change, the test control signal output unit Even if the switching element is turned on by outputting a test control signal, the engagement of the input / output shaft of the automatic transmission does not change, for example, the cutoff circuit is shut off while the automatic transmission is being controlled. The function can be diagnosed. As a result, it is possible to diagnose the interruption circuit while suppressing the restriction on the diagnosis time.

Functional block diagram showing a part of the vehicle control system in the first embodiment Electrical configuration diagram of solenoid valve drive circuit for operating automatic transmission Correspondence diagram of shift state and clutch, brake, one-way clutch Timing chart showing time change of relationship between solenoid valve drive instruction signal and switching element control signal Flow chart showing processing performed from start of control device to power off Flow chart showing failure diagnosis processing The figure showing the voltage change of the charge storage node after turning off the power shutdown switch The flowchart which shows the process in the case of performing a fault diagnosis process after IGOFF about 2nd Embodiment Flowchart showing processing at the time of startup of the control device when performing failure diagnosis processing after IGOFF Flow chart showing failure diagnosis processing Electrical configuration diagram of a solenoid valve drive circuit for operating an automatic transmission according to the third embodiment

  Hereinafter, some embodiments of the automatic transmission control device constituting the vehicle control system will be described. In the following embodiments, parts having the same function or similar functions between the embodiments are denoted by the same reference signs or similar signs (for example, the hundreds are changed by the same number in the tenth place and the first place or the subscript a , B, etc.), and the description will be omitted as necessary in the second and third embodiments.

(First embodiment)
1 to 7 are explanatory diagrams of the first embodiment. FIG. 1 shows a part of the vehicle control system 1. As shown in FIG. 1, the vehicle control system 1 mainly includes an engine system 2 that serves as a prime mover, and an automatic transmission 3 that transmits a rotational driving torque of an output shaft of the engine system 2 to a wheel (not shown). The automatic transmission 3 includes a torque converter 4 and a transmission mechanism 5 and is connected to an automatic transmission control device (hereinafter abbreviated as a control device) 6. In addition, a range detection device 8, a braking control device 9, a display control device 10 and the like are connected to the control device 6 through, for example, an in-vehicle communication line 7. A display 11 such as a liquid crystal display is connected to the display control device 10. In addition, the control device 6 detects an input rotational speed detector that detects the rotational speed of the input rotational shaft that is input from the torque converter 4 to the transmission mechanism 5, and detects the rotational speed of the output rotational shaft that is output from the transmission mechanism 5. An output rotational speed detector (none of which is shown) is connected.

  The engine system 2 controls the rotational driving force of the engine output shaft in accordance with an operation amount of an accelerator (not shown). The engine system 2 is an internal combustion engine such as a gasoline engine or a diesel engine. Torque converter 4 transmits the rotational driving force of the output shaft of engine system 2 to the input shaft of transmission mechanism 5 through liquid (not shown).

  The transmission mechanism 5 includes a plurality of gears using planetary gears for switching the transmission gear ratio between the input shaft and the output shaft, a plurality of clutches C1 to C3, a one-way clutch F1 and a brake B1 to B1 connected to these gears. B2 and a hydraulic circuit (none of which is shown) for controlling the clutches C1 to C3 and F1 and the brakes B1 and B2 are provided, and the clutches C1 to C3 and F1 and the brakes B1 and B2 are engaged / In this configuration, the gear ratio of the input / output shaft is switched in accordance with the release adjustment. The hydraulic pressures for operating the clutches C1 to C3 and F1 and the brakes B1 and B2 depend on the solenoid valve 12 (solenoid valve: see 12a to 12c in FIG. 2 or 12a to 12f in FIG. 11) provided in the hydraulic circuit. Controlled. Hereinafter, the solenoid valves 12a to 12c or 12a to 12f will be described as a generic name or a part thereof as the solenoid valve 12 as necessary.

  The solenoid valve 12 is configured using, for example, a three-way solenoid valve. A plunger (movable iron core) is used as the mover for the electromagnetic valve 12. At the time of non-pressure control, the state of the plunger is maintained and the oil pressure is not changed, but when a force is applied to the plunger, the plunger moves in accordance with this action to change the oil pressure. The control device 6 controls energization of the drive coils L (see La to Lc in FIG. 2 and La to Lf in FIG. 11) of the electromagnetic valve 12 provided in the hydraulic circuit in order to control the operation of the plunger. Hereinafter, the driving coils La to Lc or La to Lf of the electromagnetic valve 12 will be described as a generic name or a part thereof as the driving coil L of the electromagnetic valve 12 as necessary. The hydraulic circuit includes an electromagnetic valve drive circuit 13 shown in FIG. 2 as an electrical configuration for controlling energization of the drive coil L of the electromagnetic valve 12.

  FIG. 2 shows the electrical configuration of the solenoid valve drive circuit 13. As shown in FIG. 2, the solenoid valve drive circuit 13 is provided for energizing and controlling the drive coils La to Lc of the solenoid valves 12a to 12c to drive the solenoid valves 12a to 12c. In FIG. 2, only the solenoid valve drive circuit 13 for one group G1 is illustrated for convenience of explanation of the first embodiment. The electromagnetic valve drive circuit 13 is a circuit that controls the engagement / release state of the clutch C1, the brake B1, and the wayway clutch F1.

  This solenoid valve drive circuit 13 for one group G1 is a shut-off that can shut off the power supply to the drive coils La to Lc of the solenoid valves 12a to 12c by the power source 15 connected to the power supply node N1 at the time of fail safe. A circuit 16 is provided. The shut-off circuit 16 includes a power shut-off switch 17 connected to all energization paths from the power node N1 to the solenoid valves 12a to 12c of the one group G1, and a control signal output by the control device 6 at normal times. It is turned on in response and turned off at the time of fail-safe.

  Further, a charge storage circuit 18 is provided between the power cutoff switch 17 and the switching elements 14a to 14c. The control device 6 turns on the plurality of switching elements 14a to 14c connected in series to the drive coils La to Lc of the plurality of electromagnetic valves 12a to 12c after the power cutoff switch 17 of the cutoff circuit 16 is turned on. The energization control is performed on each of the driving coils La to Lc by performing the off control.

  A specific connection example will be described. Each of the plurality of switching elements 14a to 14c is configured by, for example, a P-channel type MOS transistor. The sources of these MOS transistors are commonly connected at the node N2, the drains are respectively connected to one ends of the driving coils La to Lc, and the other ends of the driving coils La to Lc are connected to the ground node N3. ing. The power cutoff switch 17 constituting the cutoff circuit 16 is constituted by, for example, a P channel type MOS transistor. The source of the MOS transistor is connected to the power supply node N1, and the drain is connected to the node N2.

  The charge storage circuit 18 includes a plurality of resistors 19 and 20 connected in series between the node N2 and the ground node N3, and a capacitor 21 connected in parallel to a part or all of the resistors 20, and includes a power cutoff switch. When the switch 17 is turned on, the capacitor 21 is charged from the power supply 15. The capacitor 21 of the charge storage circuit 18 is provided to prevent chattering and is provided to stabilize the voltage at the node N2. The voltage at the terminal node N4 of the capacitor 21 of the charge storage circuit 18 is input to the control device 6. The voltage of the node N2 may be input to the control device 6. Thereby, the control device 6 can detect the voltage of the charge storage node N4 or N2 of the charge storage circuit 18.

  The range detection device 8 shown in FIG. 1 detects a range corresponding to the position of the shift lever operated by the driver, for example. The positions of the shift lever are a parking (P) range, a reverse (R) range, a neutral (N) range, a drive (D) range, and the like. The control device 6 can input the information of the detection range of the range detection device 8 through the communication line 7. For example, the driver can perform a shift operation in a predetermined order when operating the shift lever. For example, the parking (P) range, reverse (R) range, neutral (N) range, drive (D) Shift operation is possible in the order of the range or in the reverse order.

  The brake control device 9 has a well-known configuration that receives a brake pedal operation (not shown) and performs brake control. The control device 6 can substantially execute the brake control by outputting a brake command to the brake control device 9. It has become.

  The control device 6 is mainly composed of one or a plurality of microcomputers including a CPU 22 and a memory 23 such as a RAM, a ROM, and a flash memory. The memory 23 is also used as a non-transition actual recording medium. The control device 6 causes the CPU 22 to execute various programs (for example, a test cutoff command output unit, a test energization command output unit, a determination waiting time standby unit, a predetermined time after the normal condition is established) by executing a program stored in the memory 23. A standby unit and a function as a standby unit for a predetermined time after the failure condition is established) are realized.

Hereinafter, various operations will be described. First, the relationship between the engagement states of the clutches C1 to C3 and F1 and the brakes B1 and B2 and the shift speed of the automatic transmission 3 will be described.
<Relationship between engagement state of clutches C1 to C3 and F1 and brakes B1 and B2 and a gear position of the automatic transmission 3>
FIG. 3 shows a correspondence table of the engagement states of the clutches C1 to C3 and F1 and the brakes B1 and B2 and the shift stages of the automatic transmission 3. In FIG. 3, P is a parking stage, REV is a reverse stage, N is a neutral stage, 1ST, 2ND, 3RD, 4TH, 5TH, and 6TH are forward shift stages (1st to 6th speeds). Each of the clutches C1 to C3, F1 or the brakes B1 and B2 is in an engaged state, and “not described” indicates a non-engaged state, that is, a released state.

  The control device 6 realizes a shift speed required according to the range detected by the range detection device 8 among the multiple shift speeds of the speed change mechanism 5 for the clutches C1 to C3, F1 and the brakes B1 and B2. Then, a predetermined combination of engagement / release states corresponding to the gear position is executed. For example, when the range detection device 8 detects the drive (D) range and this information is transmitted to the control device 6, the control device 6 sequentially switches between the first forward speed 1ST to the sixth forward speed 6TH. The engagement / release states of the clutches C1 to C3 and F1 and the brakes B1 and B2 are sequentially switched according to the step switching state. For example, when the range detection device 8 detects the reverse (R) range and this information is transmitted to the control device 6, the clutch C3 and the brake B2 are engaged, and the clutch C1, C2, the brake B1 and the one-way clutch F1 is set to the release state.

<Normal solenoid valve drive control>
FIG. 4 shows the correspondence between the drive instruction signal for the electromagnetic valve 12a generated in the upper layer when the CPU 22 of the control device 6 executes the application program stored in the memory 23 and the on / off control signal for the switching element 14a. Indicates.

  For example, when a drive instruction signal for the electromagnetic valve 12a for controlling the engagement state of the clutch C1 is generated by an application program, the control device 6 energizes the drive coil La of the electromagnetic valve 12a of the target clutch C1 for a predetermined period of time. Move. At this time, in order to change the hydraulic pressure by the initial movement of the plunger, the drive coil La is energized continuously for a predetermined time T1. When the drive coil La is energized continuously for a predetermined time T1, the clutch C1 is engaged.

  After energizing the driving coil La continuously for a predetermined time T1, the control device 6 maintains the plunger in a moving state by turning on and off the switching element 14a by, for example, a PWM signal pulse in the period T2. The engaged state of the clutch C1 is maintained. Therefore, during the period T2, the movement of the plunger is maintained by periodically exciting at predetermined excitation time intervals.

  At this time, in particular, the oil pressure changes according to the duty ratio of the PWM signal output from the control device 6, but the engagement state of the clutch C1 changes according to this oil pressure. In particular, the greater the duty ratio of the PWM signal, the greater the hydraulic pressure and the greater the degree of engagement of the clutch C1.

  After that, when the drive instruction signal for the electromagnetic valve 12a of the clutch C1 is turned off, the control device 6 stops energization to the drive coil La of the electromagnetic valve 12a of the clutch C1 in response to turning off the switching element 14a. Then, when the plunger returns to the original position, the clutch C1 is released, and the released state is maintained. Although the description is omitted here, the control of the engagement / release states of the other brakes B1 and the one-way clutch F1 is the same, and the control of the engagement states of the other clutches C2 and C3 and the brake B2 is performed similarly. Is called.

  The control device 6 selects the target electromagnetic valve 12 among the electromagnetic valves 12 of the clutches C1 to C3 and the brakes B1 and B2 according to the range detected by the range detection device 8, and synchronizes the drive instruction signal. The electromagnetic valve 12 is driven by this.

<Processing from starting to stopping of the control device 6>
FIG. 5 is a flowchart showing the processing contents from when the operating power is supplied to the control device 6 until the power is turned off. The vehicle is provided with a power switch such as an ignition switch. When the ignition switch is turned on by the driver (ACC), power is supplied to each block including the control device 6. At this time, the control device 6 is started by being supplied with power (S1), but thereafter, the failure diagnosis processing of the cutoff circuit 16 is performed until the power supply for operation is turned off (S8) (S5).

  In the present embodiment, as shown in FIG. 5 in particular, when the control device 6 is started in S1, the power cutoff switch 17 of the cutoff circuit 16 is turned on (S2), but then the ignition switch is IGON by the driver. After (S3) and before IGOFF is made (YES in S7), the control device 6 executes failure diagnosis processing of the cutoff circuit 16 (S5).

  When the control device 6 executes the failure diagnosis process in S5, a flag indicating that the failure diagnosis has been completed is stored in the internal memory 23. The control device 6 determines whether or not the failure diagnosis has been completed in S4 while being IGON, and does not execute the failure diagnosis process when determining that the failure diagnosis has been completed (NO in S7 → YES in S4) ). As a result, the control device 6 executes the fault diagnosis process once after it is IGON and before it is IGOFF. When the control device 6 determines that a failure has occurred in the failure diagnosis process of S5, the control device 6 notifies the user by lighting or blinking a warning light on the display 11 through the display control device 10 connected to the communication line 7 (S6). ). This can prompt the driver to check or maintain.

  A detailed example of the failure diagnosis process of S5 in FIG. 5 is shown in FIG. The processing steps S11 to S24 shown in FIG. 6 are periodically executed from when the ignition switch is IGON until when it is IGOFF.

  As shown in FIG. 6, first, the control device 6 measures the timing at which all the solenoid valves 12a to 12c in the group G1 are turned off in S11. More specifically, the control device 6 measures the timing at which the solenoid valves 12 a to 12 c are all stabilized in the off state according to the range detected by the range detection device 8 and the speed change state of the speed change mechanism 5.

  For example, when the current shift speed is 5TH, as shown in FIG. 3, the clutch C1, the brake B1, and the one-way clutch F1 are all in the released state, so that they are driven by the solenoid valve drive circuit 13 of FIG. All the solenoid valves 12a to 12c are turned off.

  The control device 6 measures the timing at which the current shift speed is 5TH and the shift state of the transmission mechanism 5 is stabilized, and determines that the condition of S11 is satisfied. Although not described here, the control device 6 determines that the condition of S11 is satisfied even when the range is detected by the range detection device 8 as a parking (P) range or a neutral (N) range. May be.

  When the condition of S11 is not satisfied, the control device 6 determines NO in S11, exits the processing routine, and waits for the timing satisfying the condition of S11. And the control apparatus 6 selects the electricity supply path | route of the solenoid valve 12 in S12, when the timing which satisfy | fills the conditions of S11 exists.

  The current shift stage or the current range is defined according to the engagement / release state of the input / output shaft of the automatic transmission 3, and the selection condition for the energization path of the solenoid valve 12 is the current shift stage or Solenoid valve that satisfies the condition that the engagement of the input / output shaft of the automatic transmission 3 does not change even when energized from the current range through the driving coil L of the target solenoid valve 12, and does not affect vehicle travel It is desirable to target 12 energization paths.

  For example, when the current shift speed is 5TH, for example, if the clutch does not affect vehicle travel even if the one-way clutch F1 is engaged, the energization path of the drive coil Lc for the one-way clutch F1 is targeted for the electromagnetic valve 12c. Is selected.

  In S13, the control device 6 confirms whether or not the selected solenoid valve 12c or the drive system of the solenoid valve drive circuit 13 has already failed. When the solenoid valve 12c or its solenoid valve drive circuit 13 (for example, the switching element 14c) fails, the control device 6 determines that a failure has occurred by executing a diagnosis process (not shown) at a timing different from the failure diagnosis process. This is stored in the internal memory 23. Therefore, the control device 6 can determine whether or not the solenoid valve 12c selected in S13 or the solenoid valve drive circuit 13 has already failed. After exiting the processing routine, another timing satisfying the conditions of S11 and S13 is also waited after this.

  If the solenoid valve 12c and its solenoid valve drive circuit 13 have not failed, the control device 6 determines NO in S13, and turns off the power cutoff switch 17 in S14 (S14). The off control signal of the power shutoff switch 17 at this time corresponds to a “test shutoff command”, and the control device 6 functions as a test shutoff command output unit.

  When the control device 6 controls the power-off switch 17 to be turned off so that the power-off switch 17 operates normally, the power source 15 is not energized to the charge storage nodes N2 and N4. However, while the power shut-off switch 17 is on, charges are stored in the capacitor 21 of the charge storage circuit 18, and the voltages at the charge storage nodes N2 and N4 rise to the vicinity of the power supply voltage.

  Therefore, the control device 6 turns on the switching element 14c for driving the selected electromagnetic valve 12c for a predetermined time T3 (S15). At this time, the ON control signal of the switching element 14c corresponds to a “test control signal”, and the control device 6 functions as a test control signal output unit.

  Here, the predetermined time T3 is adjusted to a time significantly shorter than the above-mentioned predetermined time T1, as shown in FIG. 7 in relation to the length of the predetermined time T1. As described above, the predetermined time T1 is the time required to change the hydraulic pressure based on the operation of the plunger during the normal drive control of the solenoid valve 12. For this reason, even if the control device 6 controls the switching element 14c to be on only for a moment during the predetermined time T3, the plunger does not move for the first time and the hydraulic pressure does not change substantially. Therefore, the control device 6 turns on the switching element 14c for a predetermined time T3, so that a current that satisfies the condition that the engagement of the input / output shaft of the automatic transmission 3 does not change flows through the drive coil Lc of the solenoid valve 12c. The charge stored in the capacitor 21 of the charge storage circuit 18 can be discharged to the ground node N3.

  In S16, the control device 6 determines whether or not the waiting time count value for determination is equal to or greater than a predetermined value, and exits the processing routine of FIG. 6 until the wait time counter is equal to or greater than the predetermined value. The control device 6 waits while repeating the processes of S11 to S17, but when the determination waiting time counter reaches a predetermined value or more and the determination waiting time Ta elapses, it is determined as YES in S16, and the process proceeds to S18. To do. When the process proceeds to S18, the determination waiting time counter is cleared. Note that the determination waiting time Ta is determined when the switching element 14 is turned on from the OFF state and the charge is extracted from the charge storage node N4 through the drive coil L of the electromagnetic valve 12 and is operating normally. The detection voltage is adjusted in advance to a time that satisfies the condition that the detection voltage is lower than the normal predetermined value Vth.

  Thereafter, the control device 6 determines in S18 whether or not the voltage of the charge storage node N4 is lower than the normal predetermined value Vth. If the power shut-off switch 17 is normally turned off and the switching element 14c for driving the solenoid valve 12c is normally turned on, the charge stored in the capacitor 21 is rapidly passed through the switching element 14c and the driving coil Lc for the solenoid valve 12c. As a result, the voltage of the charge storage node N4 rapidly decreases and becomes lower than the normal predetermined value Vth. Therefore, control device 6 determines that the normal condition is satisfied if the voltage at charge storage node N4 falls below normal predetermined value Vth in S18.

<Standby processing for a predetermined time Tb after the normal condition is satisfied>
When it is determined that the normal condition is satisfied, the control device 6 determines YES in S18, starts counting the time counter after the normal condition is satisfied in S19 and S20, and continues to process steps S11 to S16 until a predetermined time Tb elapses after the normal condition is satisfied. And it waits, repeating S18-S20. The control device 6 clears the time counter after the normal condition is satisfied and proceeds to S22 when it determines NO even once in S18 while repeatedly waiting for the processing steps S11 to S16 and S18 to S20 (this processing is shifted to S22). See below).

  The controller 6 determines that the predetermined time Tb has elapsed after the normal condition is satisfied (YES in S19) when the time counter after the normal condition is satisfied exceeds a predetermined value without determining NO in S18. (S21). See the time variation of “voltage of charge storage node in normal state” in FIG. Note that standby processing for a predetermined time Tb after the normal condition is satisfied may be provided as necessary.

<Standby processing for predetermined time Tc after failure condition is satisfied>
When the determination waiting time Ta has elapsed in S16 of FIG. 6 and the voltage of the charge storage node N4 does not fall below the normal predetermined value Vth in S18, the control device 6 determines NO in S18, and after the failure condition is satisfied The time counter is counted, and the process steps S11 to S16, S18, S22, and S23 are repeated until a predetermined time Tc elapses after the failure condition is satisfied.

  Here again, the control device 6 clears the time counter after the failure condition is satisfied if it is determined to be YES even once in S18, shifts to S19, and executes the waiting process for the predetermined time Tb after the normal condition is satisfied. The control device 6 determines that the predetermined time Tc has elapsed after the failure condition is satisfied when the time counter after the failure condition is satisfied is greater than or equal to a predetermined value without determining YES in S18, and determines YES and determines the failure in S22 (S24). ). Refer to the time variation of “node voltage at failure (part 1)” in FIG. Similarly, a standby process for a predetermined time Tc after the failure condition is satisfied may be provided as necessary. The lengths of the predetermined times Tc and Tb may be either longer or shorter.

<When shifting to failure condition after normal condition is satisfied>
Further, as described above, when the determination waiting time Ta has elapsed in S16, if the voltage of the charge storage node N4 falls below the normal predetermined value Vth in S18, the control device 6 determines YES in S18 and is normal. The process waits while repeating steps S11 to S16 and S18 to S20 until the predetermined time Tb after the normal condition is satisfied and the predetermined time Tb has elapsed after the normal condition is satisfied, but for some reason until the predetermined time Tb elapses after the normal condition is satisfied. When the voltage of the charge storage node N4 becomes equal to or higher than the normal predetermined value Vth, it is determined NO in S18, the counter is cleared after the normal condition is satisfied, and the time counter is started after the failure condition is satisfied in S22 and S23. Let Refer to the temporal change of “node voltage at the time of failure (part 2)” in FIG.

  Therefore, even after the normal condition is satisfied, the voltage of the charge storage node N4 becomes equal to or higher than the normal predetermined value Vth before the predetermined time Tb elapses after the normal condition is satisfied, so that the failure condition (the voltage of the node N4 is normal) If the predetermined condition Vt does not fall below the predetermined value Vth, a failure determination is made if the normal condition (the voltage at the node N4 is lower than the normal predetermined value Vth) does not hold even if the predetermined time Tc elapses after the failure condition is satisfied. (S24).

<Comparative example>
The characteristic of “voltage of the charge storage node at normal time” shown in FIG. 7 also shows the voltage drop characteristic Pa of the comparative example considered by the inventors. This voltage drop characteristic Pa shows the voltage drop characteristic when the power shut-off switch 17 is controlled to be turned off in S14 while omitting the processes of steps S11 to S13 and S15 in FIG. That is, the voltage drop characteristic of the charge storage node N4 when the charge is spontaneously discharged from the charge storage node N4 when the power cutoff switch 17 is controlled to be off is shown.

  When this discharge condition is used, when all of the switching elements 14a to 14c for driving the solenoid valves 12a to 12c are in the off state, it takes a considerable time for the stored voltage of the charge storage circuit 18 to spontaneously discharge. Therefore, a waiting time Tz (for example, about 2 seconds) that significantly exceeds the above-described time Ta is required.

  When the ignition switch is IGON, the control device 6 performs shift control by the automatic transmission 3, and therefore frequently performs shift changes and shift speed changes. For this reason, it is difficult to ensure the standby time Tz during the driving operation of the actual vehicle, and it is difficult to inspect the interruption function of the interruption circuit 16 before the IGON and the IGOFF.

<Conceptual summary in this embodiment>
In short, according to the present embodiment, the control device 6 outputs an off control signal as a test cutoff command to the power cutoff switch 17 of the cutoff circuit 16 (S14), and also relates to the input / output shaft of the automatic transmission 3. An ON control signal for energizing the solenoid valve 12c with a current that satisfies a condition that does not change is output as a test control signal to the switching element 14c for a predetermined time T3 that is significantly shorter than the predetermined time T1, for example (S15). Accordingly, it is diagnosed whether or not the cutoff circuit 16 normally shuts off (S16 to S24).

  Thus, the control device 6 can diagnose whether or not the cutoff circuit 16 has failed by referring to the voltage of the charge storage node N4 of the charge storage circuit 18, for example, as in the technique described in Patent Document 1. There is no need to detect the current. In particular, as in the comparative example, without requiring a long standby time Tz, normal determination can be made by waiting for the determination waiting time Ta and normal conditions being satisfied, and in this case, failure diagnosis can be completed quickly.

  From the time when the control device 6 outputs the ON control signal to the switching element 14c, the control device 6 waits for the determination waiting time Ta when the detection voltage of the charge storage node N4 is lower than the normal predetermined value Vth if it is operating normally (S16, S16). S17) Whether or not the power shutoff switch 17 is normally shut off is determined according to the detection voltage of the charge storage node N4 when the determination waiting time Ta has elapsed. Therefore, it is possible to accurately diagnose whether or not the power cutoff switch 17 is normally shut off.

  The control device 6 waits for the determination waiting time Ta, determines that the normal condition is satisfied when the detection voltage of the charge storage node N4 falls below the normal predetermined value Vth, and further waits for a predetermined time Tb after the normal condition is satisfied ( S19, S20), if the detection voltage of the charge storage node N4 does not exceed the normal predetermined value Vth before the predetermined time Tb elapses after the normal condition is established, it is diagnosed that the cutoff circuit 16 is operating normally. (S21). Therefore, normality can be determined with high reliability.

  The control device 6 waits for the determination waiting time Ta, determines that the failure condition is satisfied when the detection voltage of the charge storage node N4 does not fall below the normal predetermined value Vth, and further waits for the predetermined time Tc after the failure condition is satisfied. (S22, S23) If the detection voltage of the charge storage node N4 does not fall below the normal predetermined value Vth before the predetermined time Tc elapses after the failure condition is established, it is diagnosed that the cutoff circuit 16 has failed (S24). For this reason, failure determination can be performed with high reliability.

  In particular, the failure diagnosis process of the cutoff circuit 16 can be executed after the ignition switch is turned on and before the IGOFF, and the failure diagnosis process of the cutoff circuit 16 is performed even while the control device 6 is controlling the automatic transmission 3. Can be executed. In addition, the user can be notified at the timing when the failure occurs.

  Even if the solenoid valve 12c to be driven by the switching element 14c is energized to the drive coil Lc of the target solenoid valve 12c from the current shift stage (for example, 5TH) or the current range (for example, parking range, neutral range). In the automatic transmission 3, the electromagnetic valve 12c of the one-way clutch F1 that satisfies the condition that does not affect the current gear position is targeted. For this reason, safety can be improved.

  Further, in the technique described in Patent Document 1, it is assumed that each solenoid of a group can be normally energized in the failure diagnosis process, and the solenoid is energized to check whether the power is cut off after power-off. Is on. For this reason, for example, when the solenoid is out of order, it cannot be determined that the power can be shut off normally.

  According to the present embodiment, whether or not the energization path of the solenoid valve 12c selected in S13 of FIG. 6 or its solenoid valve drive circuit 13 (the switching element 14c for energizing the solenoid valve 12c) has already failed. The switching element 14c corresponding to the solenoid valve 12c selected on the condition that it is determined that there is no failure is turned on, the charge at the charge storage node N4 is discharged, and the voltage at the charge storage node N4 is detected to diagnose the failure. Processing. That is, the voltage of the charge storage node N4 is detected after confirming that the energization path of the solenoid valve 12c and the solenoid valve drive circuit 13 (the switching element 14c corresponding to the solenoid valve 12c) are operating normally. Since the failure diagnosis process of the cutoff circuit 16 is executed in step S1, it can be accurately determined whether the cutoff circuit 16 is operating normally or has failed.

(Second Embodiment)
8 to 10 show additional explanatory views of the second embodiment. In the second embodiment, when there is no opportunity to diagnose whether or not the cutoff circuit 16 normally shuts off until the ignition switch is IGON and IGOFF, the cutoff circuit 16 is normally switched on after the IGOFF. It is characterized in that the control device 6 is provided with a function as an off-time processing unit that diagnoses whether or not to shut off and backs up the diagnosis result and then turns off the power.

  For example, when the control device 6 executes the technique according to the first embodiment, there may be no opportunity to diagnose whether or not the cutoff circuit 16 normally shuts off while being IGON. That is, for example, as described in the first embodiment, if it is a necessary start condition of S11 in FIG. 6 that the gear position is changed to 5TH, for example, NO in S11 until the ignition switch is changed from IGON to IGOFF. By continuing the determination, the normal determination at S21 or the failure determination at S24 in FIG. 6 may not pass and the IGOFF may be performed at S7 in FIG. 6, and the control device 6 may be turned off at S8. That is, for example, when the ignition switch is turned on without being changed to 5TH after the ignition switch is turned on.

  In such a case, as shown in S31 to S33 of FIG. 8, after IGOFF, on the condition that the failure diagnosis has not been completed in S31, the failure diagnosis processing is performed in S32, and the diagnosis result is backed up in the memory in S34. To S35, for example, the power source of the control device 6 may be turned off by itself. The control device 6 desirably executes the failure diagnosis processing shown in FIG. 6 when executing the failure diagnosis processing of S32. In this case, as shown in the above-described embodiment, normal / failure determination can be performed quickly, and safety can be confirmed quickly.

  When the processes of S31 to S35 in FIG. 8 are subscribed, the process shown in FIG. 9 may be executed after the control device 6 is activated and before the ignition switch is IGON. As shown in FIG. 9, on the condition that the failure is determined in the failure diagnosis process performed when IGOFF was last performed in S36, the display control device 10 displays a warning to this effect on the display 11 in S37. Notice. Then, if the power is supplied to each block such as the control device 6, the user can grasp that there is a failure until or after the IGON.

<Modification>
The fault diagnosis process in S32 of FIG. 8 may be executed using a process excluding steps S11 to S13 and S15 of FIG. 6, as shown in FIG. The process shown in FIG. 10 is the same process as the “comparative example” described above, but the voltage drop characteristic of the charge storage node N4 when this comparative example is applied is shown by the characteristic Pa in FIG. Although it takes time for the accumulated charge of the charge accumulation node N4 to be normally discharged, the failure diagnosis processing timing of S32 in FIG. 8 is after IGOFF, and the control device 6 ends the control processing of the automatic transmission 3 Therefore, even if it takes a long time Tz (for example, about 2 seconds) for the failure diagnosis process of the cutoff circuit 16, there is no particular problem.

<Conceptual summary of this embodiment>
As described above, according to the present embodiment, when there is no opportunity to diagnose whether or not the cutoff circuit 16 normally shuts off until the ignition switch is IGON and IGOFF, The power supply is turned off after diagnosing whether or not the shutoff circuit 16 is shut off normally and backing up the diagnosis result. Therefore, even if the failure diagnosis result (normality determination, failure determination) cannot be recorded in the memory 23 after the ignition switch is IGON to IGOFF, the failure diagnosis result after the IGOFF is turned on, for example, backup means (for example, In the memory 23), it is possible to reliably execute one failure diagnosis process for one execution of IGON and IGOFF, and to prevent a decrease in diagnosis frequency.

(Third embodiment)
FIG. 11 shows an additional explanatory diagram of the third embodiment. In the third embodiment, an example using a plurality (for example, two) groups of solenoid valve drive circuits will be described.

  In the first embodiment, the electromagnetic valve driving circuit 13 for one group G1 has been described for convenience of explanation, but the electromagnetic valve driving circuit 113 for driving the clutches C1 to C3 and F1 and the brakes B1 and B2 is Actually, as shown in FIG. 11, a plurality of electromagnetic valves 12a to 12c and 12d to 12f are respectively assigned to the plurality of groups G1 and G2 and driven.

  For example, the plurality of solenoid valves 12a to 12c in the first group G1 are hydraulic control solenoid valves that control the engagement / release state of the clutch C1, the brake B1, and the wayway clutch F1, respectively. The plurality of solenoid valves 12d to 12f are hydraulic control solenoid valves that control the engagement / release states of the clutches C2 and C3 and the brake B2, respectively.

  Driving coils La to Lf are respectively provided for driving these solenoid valves 12a to 12f, and switching elements 14a to 14f for controlling energization on / off of these driving coils La to Lf are respectively connected in series. It is connected. The sources of the switching elements 14a to 14c are commonly connected to each other at a common connection node N2a, and the sources of the switching elements 14d to 14f are commonly connected to each other at a common connection node N2b.

  In the first group G1, a power cutoff switch 117a of the cutoff circuit 116 is connected between the power supply node N1 and the common connection node N2a of the switching elements 14a to 14c. Similarly, the power cut-off switch 117b of the cut-off circuit 116 is connected to the second group G2 between the power supply node N1 and the common connection node N2b of the switching elements 14d to 14f.

  A charge storage circuit 118a is configured at the node N2a. The charge storage circuit 118a includes resistors 19a and 20a and a capacitor 21a in the illustrated form. In addition, a charge storage circuit 118b is configured at the node N2b. The charge storage circuit 118b includes resistors 19b and 20b and a capacitor 21b in the illustrated form. Since these detailed connection relationships are the same as in the description of the first embodiment, the description thereof is omitted.

  When the control device 6 performs failure diagnosis of the power cutoff switches 117a and 117b of the cutoff circuits 116 of the first and second groups G1 and G2, the failure diagnosis is performed using the same method as that described in the first embodiment. it can.

  For example, when the control device 6 diagnoses a failure with respect to the power cutoff switch 117a of the first group G1, the gear position that satisfies the condition of S11 in FIG. 6 is 5TH. For this reason, when the shift speed is 5TH and the clutches C1 to C3 and the like reach a stable engaged state, the failure diagnosis of the power cutoff switch 117a can be performed.

  As shown in FIG. 3, when the failure diagnosis is performed on the power cut-off switch 117a of the second group G2, the gear position that satisfies the condition of S11 in FIG. 6 is 2ND. For this reason, when the gear position is 2ND, it becomes a candidate for failure diagnosis, and when the gear position becomes 2ND and the clutches C1 to C3 and the like have reached a stable engaged / released state, the power cutoff switch 117b can be diagnosed. At this time, if it is possible to select an appropriate energization path to the solenoid valve 12 that may be ON-controlled only for a short time T3 among the clutches C2 and C3 and the brake B2 to be controlled in the second group G2, the failure diagnosis shown in FIG. The process can diagnose the failure of the power cut-off switch 117b of the second group G2.

  In either the first or second group G1 or G2, failure diagnosis processing for the power cut-off switches 117a and 117b of the cut-off circuit 116 is performed on the condition that the current range is the parking (P) range or the neutral (N) range. Can be executed.

  The failure diagnosis processing shown in FIG. 6 is executed while the ignition switch is IGON to IGOFF, for example, during the control of the automatic transmission 3, that is, while the vehicle is running. For example, the current gear position is assumed to be 2ND. When the control device 6 determines that the power cut-off switch 117b of the second group G2 has failed, the current shift speed is determined without using the clutches C2 and C3 and the brake B2 of the second group G2 determined to be defective. The automatic transmission 3 may be continuously controlled by switching.

  At this time, the control device 6 releases all the engagement states of the clutches C2, C3, and the brake B2 by turning off all the switching elements 14d to 14f for driving the solenoid valves 12d to 12f of the second group G2, for example. Preferably, the control device 6 controls the engagement / release state of the automatic transmission 3 using the clutch C1, the brake B1, and the one-way clutch F1 of the first group G1 as necessary, and sets the current shift speed to, for example, It may be switched to 5TH and evacuated. In this case, the control device 6 has a function as a retraction control unit.

  As a result, even when the power cutoff switch 117b of the second group G2 is determined to be faulty while the vehicle is running, the other first solenoid valves 12d to 12f of the second group G2 that are determined to be faulty are not used. By using the solenoid valves 12a to 12c of the group G1, it becomes possible to retreat immediately and safely.

<Conceptual summary of this embodiment>
According to the present embodiment, when the power cut-off switch 117b of one group G2 is diagnosed as a failure, the current valves are switched by driving the solenoid valves 12a to 12c of other groups G1 different from the one group G2. Therefore, it is possible to evacuate safely.

(Other embodiments)
The present invention is not limited to the above-described embodiments, and for example, the following modifications or expansions are possible.

  The cutoff circuits 16 and 116 are configured using MOS transistors as the power cutoff switches 17, 117a and 117b, respectively. However, other types of switching elements may be used, or a plurality of switching elements may be used. it can.

  Although the control device 6 generates an impulse having a time T3 shorter than the time T1 as a test control signal, the charge stored in the charge storage nodes N4 and N2 is discharged to the ground node N3 without changing the hydraulic pressure. However, the present invention is not limited to this. For example, instead of this impulse, a plurality of pulses may be generated and PWM duty control may be performed to discharge the accumulated charges in the charge accumulation nodes N4 and N2 to the ground node N3. A “diagnosis unit” that enables failure diagnosis of the cutoff circuits 16 and 116 may be provided outside the control device 6.

  You may combine the structure and function of several embodiment mentioned above. An aspect in which a part of the above-described embodiment is omitted as long as the problem can be solved can be regarded as the embodiment. Moreover, all the aspects which can be considered in the limit which does not deviate from the essence of the invention specified by the wording described in the claims can be regarded as the embodiment.

  Although the present disclosure has been described based on the above-described embodiments, it is understood that the present disclosure is not limited to the embodiments and structures. The present disclosure includes various modifications and modifications within the equivalent range. In addition, various combinations and forms, as well as other combinations and forms including one element, more or less, are within the scope and spirit of the present disclosure.

  In the drawing, reference numeral 6 denotes an automatic transmission control device (a test shutoff command output unit, a test control signal output unit, a determination waiting time standby unit, a predetermined time standby unit after a normal condition is established, a predetermined time standby unit after a failure condition is established, and an evacuation control ), 12a to 12f are solenoid valves, 14a to 14f are switching elements, 16, 116 are cutoff circuits, La to Lf are driving coils, N1 is a power supply node, N2 and N4 are charge storage nodes, and Vth is a normal predetermined value. , Ta is a determination waiting time, Tb is a predetermined time after the normal condition is satisfied, and Tc is a predetermined time after the failure condition is satisfied.

Claims (8)

The switching elements (14a-14f) connected to the energization path from the power supply node (N1) to the drive coils (La-Lf) of the solenoid valves (12a-12f) are switched to energize the drive coils of the solenoid valves. By controlling, the internal engagement / disengagement state of the automatic transmission (3) for switching the gear ratio of the input / output shaft is controlled, and energization from the power supply node to the drive coil of the solenoid valve is performed at the time of fail safe. The shut-off circuit (16, 116) that enables shut-off is driven, and a voltage detected from the charge accumulation nodes (N2, N4) that accumulates charges between the power supply node and the switching element is used. An automatic transmission control device (6) enabling fault diagnosis;
A test cutoff command output unit (6, S14) for outputting a test cutoff command for diagnosing whether or not the cutoff circuit normally shuts down to the cutoff circuit;
If the switching element is turned on from the off state of the switching element and the charge is extracted from the charge accumulation node through the driving coil of the solenoid valve, if the normal operation is performed, the detection voltage of the charge accumulation node is a normal predetermined value. The test for energizing the drive coil of the solenoid valve with a test control signal that satisfies a condition of lower than (Vth) and satisfying a condition that does not change the engagement of the input / output shaft of the automatic transmission. A test control signal output unit (6, S15) for outputting a control signal to the switching element,
It is possible to diagnose whether or not the shut-off circuit normally shuts down in response to the test shut-off command output unit outputting a test shut-off command and the test control signal output unit outputting a test control signal (S16 to S24). Automatic transmission control device. An automatic transmission control device in which an ignition switch is IGON and the operation power is turned off after the ignition switch is IGOFF,
A diagnosis unit (S16 to S24) for diagnosing whether or not the shut-off circuit normally shuts off;
The automatic transmission control device according to claim 1, wherein the diagnosis unit diagnoses whether or not the shut-off circuit normally shuts off until the ignition switch is IGON and IGOFF.   The energization path of the solenoid valve energized through the switching element from which the test control signal output unit outputs the test control signal is determined according to the engagement / release state of the input / output shaft of the automatic transmission. 3. The energization path of the electromagnetic valve that satisfies a condition that does not affect the current shift speed or the current range even if the target solenoid valve is driven from the shift speed or the current range is targeted. Automatic transmission control device. An automatic transmission control apparatus in which an ignition switch is IGON and the power is turned off after the ignition switch is IGOFF,
A diagnosis unit (S16 to S24) for diagnosing whether or not the shut-off circuit normally shuts off;
If there is no opportunity for the diagnosis unit to diagnose whether or not the shut-off circuit normally shuts off before the ignition switch is turned on and off, the shut-off circuit is normal after the ignition switch is turned off. An off-time processing unit (S31 to S35) for diagnosing whether or not to shut off and backing up the diagnosis result and then turning off the power;
The automatic transmission control device according to any one of claims 1 to 3, further comprising: A diagnosis unit (S16 to S24) for diagnosing whether or not the shut-off circuit normally shuts off;
The diagnostic unit
Determination to wait for a determination waiting time (Ta) when the detection voltage of the charge storage node is lower than a normal predetermined value (Vth) if the test control signal output unit outputs a test control signal and is operating normally. A waiting time waiting section (S16, S17)
The diagnosis waiting time (Ta) of the determination waiting time waiting portion is diagnosed as to whether or not the blocking circuit normally shuts off according to a detection voltage of the charge storage node when the determination waiting time (Ta) has elapsed. The automatic transmission control device according to any one of the above. The diagnostic unit
When the detection waiting time is awaited by the determination waiting time waiting unit and the detection voltage of the charge storage node falls below a normal predetermined value and a normal condition is satisfied, a normal time waiting for a predetermined time (Tb) after the normal condition is satisfied Provided with a waiting portion (S19, S20) for a predetermined time after the condition is satisfied,
If the detection voltage of the charge storage node does not exceed the normal predetermined value before a predetermined time (Tb) after the normal condition of the standby unit is satisfied after the normal condition is satisfied, the interruption circuit is diagnosed as normal. (S21) The automatic transmission control device according to claim 5. The diagnostic unit
The determination waiting time waiting unit waits for a determination waiting time, and when the detection voltage of the charge storage node does not fall below a normal predetermined value, it is determined that a failure condition is satisfied and waits for a predetermined time (Tc) after the failure condition is satisfied. A standby unit (S22, S23) for a predetermined time after the failure condition is established,
If the detection voltage of the charge storage node does not fall below the normal predetermined value before the predetermined time (Tc) after the failure condition of the standby unit is satisfied after the failure condition is satisfied, the interruption circuit is diagnosed as a failure (S24). A control device for an automatic transmission according to claim 5. The solenoid valves are provided in a plurality of groups,
When the diagnosis unit diagnoses a failure of one group of cutoff circuits,
The automatic according to any one of claims 1 to 7, further comprising a retraction control unit (6) that drives a solenoid valve of another group different from the one group to switch and retreat by changing a current gear position. Transmission control device.

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