JP6365416B2 - Shift control device - Google Patents

Description

  The present invention relates to a shift control device that can improve the safety of a shift ECU even when power is not supplied.

  In a shift-by-wire type shift control device, when a user operates a shift operation device, an electrical operation signal is output to a shift ECU (SBW-ECU), and the shift ECU drives a shift drive motor to transmit the transmission. The shift range is switched to the range instructed by the operation signal.

Japanese Patent Laid-Open No. 2008-220039

  Power is supplied to the shift ECU from the battery via the power supply line. However, if power is not supplied due to disconnection of the power supply line, the shift ECU becomes uncontrollable. In such a state, since the shift range of the transmission cannot be switched, there is a possibility that the transmission cannot be switched to a predetermined range, for example, a P (parking) range when the vehicle is stopped.

  An object of the present invention is to provide a shift control device that can switch a transmission to a predetermined range even when power is not supplied to a shift ECU due to disconnection of a power supply line or the like.

  The invention according to claim 1 is a shift control device that switches a shift range of a transmission by a shift-by-wire method, the switch that cuts off a load other than a drive source that switches the shift range of the transmission, and the switch A power connection line for connecting the upstream terminal to the power supply terminal of the transmission control device, a state in which the upstream terminal is connected to the power supply terminal, and a state where the upstream terminal is connected to the power supply terminal. And a changeover switch for switching between a state in which the connection is not established.

1 is an electrical configuration diagram of a shift control device showing a first embodiment of the present invention. Electrical circuit diagram of the power circuit Flowchart of control of shift ECU (1) Flowchart of control of shift ECU (2) Flow chart of control of other ECU Time chart

  Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. First, FIG. 1 is an electrical configuration diagram schematically showing the overall configuration of the shift control system 1 of the present embodiment. As shown in FIG. 1, a shift control system 1 includes a shift ECU (SBW-ECU) 2 as a shift control device, and an ECU (Other-ECU) 3 as another electronic control device mounted on the vehicle. It has. The power supply terminal 2 a of the shift ECU 2 and the power supply terminal 3 a of the ECU 3 are connected to a power supply line 5 derived from the battery 4 via power supply lines 6 and 7.

  A drive motor (drive source) 8 of the shift switching device of the transmission is connected between the power supply line 5 and the first terminal 2b of the shift ECU 2. The shift ECU 2 is configured so that the shift position of the transmission can be switched to a desired position by controlling energization of the drive motor 8. Further, between the power supply line 5 and the second terminal 2 c of the shift ECU 2, for example, an LED 9 is connected as a load unrelated to driving of the drive motor 8. A load such as a relay (not shown) may be used instead of the LED 9.

  The third terminal 2d of the shift ECU 2 is connected to the first terminal 3b of the ECU 3. The in-vehicle LAN of the shift ECU 2, for example, the CAN communication terminals 2 e and 2 f are connected to the CAN communication terminals 3 c and 3 d of the ECU 3.

  The shift ECU 2 includes a microcomputer 10, a CAN circuit 11, a power supply circuit 12, a first MOS-FET 13, an NPN transistor (switch) 14, and a second MOS-FET (switching switch) 15. The first MOS-FET 13 has a drain connected to the first terminal 2b, a source connected to the ground, and a gate connected to the terminal 10a of the microcomputer 10. The microcomputer 10 has a configuration in which the drive motor 8 can be controlled to be disconnected by supplying a control signal to the gate of the first MOS-FET 13 to turn on and off the first MOS-FET 13.

  The NPN transistor 14 has a collector connected to the second terminal 2c, an emitter connected to the ground, and a base connected to the terminal 10b of the microcomputer 10. The microcomputer 10 is configured to be able to control the disconnection of the LED 9 by applying a control signal to the base of the NPN transistor 14 to turn on and off the NPN transistor 14.

  The second MOS-FET 15 has a drain connected to the second terminal 2c, a source connected to the power supply terminal 2a, a gate connected to the third terminal 2d, and a third terminal 2d connected to the ground. A resistor 16 is connected between the two. In the case of this configuration, the second terminal 2 c that is the upstream terminal of the NPN transistor 14 and the power terminal 2 a of the shift ECU 2 are connected via the power connection line 31, and the second connection 2 is connected to the power connection line 31. MOS-FET 15 is provided. When the second MOS-FET 15 is turned on, the second terminal 2c is connected to the power supply terminal 2a of the shift ECU 2. When the second MOS-FET 15 is turned off, the second terminal 2c is turned on. The power supply terminal 2a of the shift ECU 2 is not connected.

  The other ECU 3 is configured to be able to turn on and off the second MOS-FET 15 by giving a control signal to the first terminal 3b, that is, the third terminal 2d (the gate of the second MOS-FET 15). Yes. Here, the power supply terminal 2 a is connected to the + B power supply in the shift ECU 2 and is connected to the input terminal 12 a of the power supply circuit 12. The disconnection detection terminal 12b of the power supply circuit 12 is connected to the terminal 10c of the microcomputer 10.

  Further, the terminal 10d of the microcomputer 10 is connected to the gate of the second MOS-FET 15 (the third terminal 2d of the shift ECU 2). As a result, the microcomputer 10 allows the second MOS-FET 15 to be turned on. Whether or not the third terminal 2d (first terminal 3b) is at a high level. Further, the terminals 10 f and 10 g of the microcomputer 10 are connected to the terminals 11 a and 11 b of the CAN circuit 11. The terminals 11c and 11d of the CAN circuit 11 are connected to the CAN communication terminals 2e and 2f.

  Next, a specific configuration of the power supply circuit 12 will be described with reference to FIG. As shown in FIG. 2, the power supply circuit 12 includes a power supply generation circuit 17 and a disconnection detection circuit 18. The power supply generation circuit 17 includes a PNP transistor 19, resistors 20 and 21, capacitors 22 and 23, and a voltage control unit 24. The PNP transistor 19 has an emitter connected to the input terminal 12 a via the resistor 20, a collector connected to the power supply output terminal 12 c, and a base connected to the voltage control unit 24. A resistor 21 is connected between the base and the emitter. A capacitor 22 is connected between the input terminal 12a and the ground, and a capacitor 23 is connected between the power output terminal 12c and the ground. The PNP transistor 19 is controlled to be turned on / off by the voltage control unit 24, so that a constant voltage of, for example, 5V is output from the power output terminal 12b as the internal power source of the shift ECU 2.

  The disconnection detection circuit 18 includes a PNP transistor 25, a resistor 26, diodes 27 and 28, a voltage control unit 29, and a comparator 30. The PNP transistor 25 has an emitter connected to the input terminal 12 a via the diode 27, a collector connected to the simple power supply terminal 31 of 5 V, for example, and the “+” input terminal of the comparator 30, and a base connected to the voltage control unit 29. ing. A resistor 26 is connected between the base and the emitter. The threshold voltage Vth is input to the “−” input terminal of the comparator 30. The output terminal 30a of the comparator 30 is connected to the disconnection detection terminal 12b. Further, an IGSW (ignition switch) signal is input to the emitter of the PNP transistor 25 via the diode 28.

  In this configuration, the PNP transistor 25 is turned on / off by the voltage control unit 29 to give a voltage higher than the threshold voltage Vth to the “+” input terminal of the comparator 30, that is, the output terminal 30 a (disconnection detection) of the comparator 30. The terminal 12b) is configured to output a high level signal. With the above configuration, for example, when the power supply line 6 is disconnected, the voltage input to the “+” input terminal of the comparator 30 becomes lower than the threshold voltage Vth. Therefore, the output terminal 30a of the comparator 30 (disconnection detection terminal 12b). Is configured to output a low level signal.

  Next, the operation of the above configuration will be described with reference to FIGS. First, FIG. 3 is a flowchart showing the contents of the first control when the disconnection of the power supply line 6 in the control of the shift ECU 2 is detected. In step S10 of FIG. 3, the microcomputer 10 of the shift ECU 2 determines whether or not the power supply line 6 of the shift ECU 2 is disconnected based on the signal level of the disconnection detection terminal 12b of the power circuit 12. Here, when the power supply line 6 is not disconnected (the disconnection detection terminal 12b is at the high level) ("NO" in step S10), the determination process in step S10 is continued. Note that the control of FIG. 3 is configured to be repeatedly executed at predetermined time intervals.

  In step S10, when the power supply line 6 is disconnected (the disconnection detection terminal 12b is at low level) ("YES"), the process proceeds to step S20, and the microcomputer 10 disconnects the shift ECU 2 (power supply line 6). Information is transmitted to another ECU 3 via the CAN circuit 11 (CAN communication). Further, in step S20, the microcomputer 10 turns off the NPN transistor 14 for controlling power interruption of the LED 9 and turns off the first MOS-FET 13 to cut off the drive motor 8. In addition, in step S20, when there are loads other than the LED 9 and the drive motor 8, the microcomputer 10 also cuts off the loads. Thereby, the control of FIG. 3 is terminated.

  FIG. 4 is a flowchart showing the contents of the second control when disconnection is detected in the control of the shift ECU 2. First, in step S110 of FIG. 4, based on the signal level of the terminal 10c of the microcomputer 10, it is determined whether or not the second MOS-FET 15 is on (the third terminal 2d and the terminal 10c are at a high level). . Here, when the second MOS-FET 15 is off (“NO” in step S110), the determination in step S110 is repeated. Note that the control in FIG. 4 is configured to be repeatedly executed at predetermined time intervals.

  When the second MOS-FET 15 is turned on in step S110 ("YES"), the process proceeds to step S120, and the microcomputer 10 continues the off state of the NPN transistor 14 for controlling power interruption of the LED 9. Subsequently, the process proceeds to step S <b> 130, and the microcomputer 10 stops functions not related to driving of the drive motor 8 (various loads (not shown) such as LIN and other load controls).

  Next, the process proceeds to step S140, and the microcomputer 10 turns on the first MOS-FET 13 and controls energization of the drive motor 8, thereby moving the shift position of the transmission to the P range. Then, the process proceeds to step S150, and it is determined whether or not the shift position of the transmission is in the P range. Although not shown, the shift ECU 2 is configured to receive information indicating the shift position from the transmission. In step S150, when the shift position of the transmission is not in the P range ("NO"), the process returns to step S140, and energization control of the drive motor 8 is continued.

  Thereafter, in step S150, when the shift position of the transmission is in the P range (“YES”), the process proceeds to step S160, where the first MOS-FET 13 is turned off and the drive motor 8 is stopped. Then, it progresses to step S170 and the information which shows completion of P range switching is transmitted to ECU3 via the CAN circuit 11 (CAN communication). Thereby, the control of FIG. 4 is terminated.

  Next, FIG. 5 is a flowchart showing the contents of the control when the disconnection detection of the shift ECU 2 in the control of the other ECU 3 is detected. First, in step S210 in FIG. 5, the ECU 3 determines whether or not there is CAN communication, that is, whether or not the disconnection information (see step S20 in FIG. 3) of the power supply line 6 has been received from the shift ECU 2. Here, when the disconnection information is not received (“NO” in step S210), the determination in step S210 is repeated. Note that the control in FIG. 5 is configured to be repeatedly executed at predetermined time intervals.

  When disconnection information is received in step S210 ("YES"), the process proceeds to step S220, and the ECU 3 determines whether or not the power supply line 7 of the ECU 3 is disconnected by a disconnection detection circuit (not shown) provided therein. Judging. Here, when the power supply line 7 of the vehicle is disconnected, that is, when the vehicle battery 4 becomes useless ("YES" in step S220), the process proceeds to step S260, and the normal power-off operation is performed. To finish the control.

  When the power supply line 7 is not disconnected in step S220 ("NO"), the process proceeds to step S230, and the ECU 3 turns on the second MOS-FET 15 in the shift ECU 2 from the first terminal 3b. Output (send) a high level signal. As a result, the second MOS-FET 15 in the shift ECU 2 is turned on.

  Subsequently, the process proceeds to step S240, and it is determined whether or not CAN communication is present, that is, whether or not information indicating completion of P range switching has been received from the shift ECU 2 (see step S170 in FIG. 4). Here, when the information indicating the completion of the P range switching is not received (“NO” in step S240), the determination in step S240 is repeated.

  In step S240, when information indicating completion of P range switching is received ("YES"), the process proceeds to step S250, where the ECU 3 turns off the second MOS-FET 15 in the shift ECU 2 from the first terminal 3b. Output (send) the signal. As a result, the second MOS-FET 15 in the shift ECU 2 is turned off. Thereby, the control of FIG. 5 is completed.

  Next, operations of the shift ECU 2 and the other ECU 3 having the above-described configuration will be described with reference to a time chart of FIG. As shown in FIG. 6A, when the disconnection of the power supply line 6 of the shift ECU 2 occurs at time t1, the disconnection detection circuit 18 of the power supply circuit 12 of the shift ECU 2 inputs to the “+” input terminal of the comparator 30. Since the voltage (disconnection detection voltage) Va to become lower than the threshold voltage Vth at time t2 (see FIG. 6B), a low level signal is output from the output terminal 30a (disconnection detection terminal 12b) of the comparator 30. Upon receiving this low level signal, the microcomputer 10 transmits disconnection information of the power supply line 6 (shift ECU 2) to another ECU 3 via CAN communication at time t2 (see FIG. 6D).

  In this case, the internal power supply voltage Vb (voltage of the power supply output terminal 12c of the power supply circuit 12) of the shift ECU 2 is reduced from the occurrence of disconnection of the power supply line 6 (time t1) due to the capacitance of the capacitors 22 and 23 of the power supply circuit 12. The power supply is held so that the microcomputer 10 can operate until the CAN communication of the disconnection information is completed. That is, at time t3 after the CAN communication is completed, the internal power supply voltage Vb of the shift ECU 2 becomes 0V.

  Further, the microcomputer 10 of the shift ECU 2 turns off the NPN transistor 14 and cuts off the LED 9 at the time t2. As a result, the voltage Vc of the collector of the NPN transistor 14 (the first terminal 2b of the microcomputer 10) becomes high level (for example, 14V) at time t2 (see FIG. 6F). At the same time, the microcomputer 10 turns off the first MOS-FET 13 and disconnects the drive motor 8 at the time t2. Thereby, the voltage Vd of the connection terminal of the drive motor 8 (second terminal 2c of the microcomputer 10) becomes high level (for example, 14V) at time t2 (see FIG. 6G).

  Thereafter, at time t4, the other ECU 3 outputs a high-level signal for turning on the second MOS-FET 15 in the shift ECU 2 from the first terminal 3b, whereby the second MOS in the shift ECU 2 is output. -The FET 15 is turned on (see FIG. 6E). As a result, since the power supply line 5 is connected to the input terminal 12a of the power supply circuit 12 via the power supply path passing through the LED 9, the voltage Vb of the power supply output terminal 12c of the power supply circuit 12 starts to rise (FIG. 6 ( c)). Further, the voltage at the power supply terminal 2a of the shift ECU 2 and the voltage Va input to the “+” input terminal of the comparator 30 also begin to rise (see FIGS. 6A and 6B).

  In this case, as shown in FIG. 6 (f), the voltage Vc at the collector of the NPN transistor 14 (the first terminal 2b of the microcomputer 10) has decreased slightly from the normal high level (for example, 14V) after time t4. It becomes a voltage (voltage dropped by the LED 9 as a load). The voltage Vb at the power supply output terminal 12c of the power supply circuit 12 also rises only to a voltage slightly lower than a normal high level (for example, 5V) (voltage dropped due to current shortage by the LED 9) (see FIG. 6C). ). Further, the voltage at the power supply terminal 2a of the shift ECU 2 is also a voltage (voltage dropped by the LED 9 as a load) slightly lower than a normal high level (for example, 14V) (see FIG. 6A). The voltage Va input to the “+” input terminal is also a voltage slightly lower than a normal high level (for example, 5 V) (voltage dropped due to current shortage by the LED 9) (see FIG. 6B).

  Next, the microcomputer 10 of the shift ECU 2 turns on the first MOS-FET 13 to turn on the drive motor 8 at time t5 (when the voltage at the power supply output terminal 12b rises to a voltage slightly lower than the normal high level). By performing energization control (see FIG. 6G), the shift position of the transmission is moved to the P range. Thereafter, when the shift position of the transmission is completely switched to the P range at time t6, the microcomputer 10 turns off the first MOS-FET 13 and stops the drive motor 8 from being disconnected (FIG. 6 (g)). In addition, information indicating completion of range switching is transmitted to another ECU 3 via CAN communication (see FIG. 6D).

  Subsequently, the ECU 3 that has received the information indicating the completion of the range switching outputs a low level signal for turning off the second MOS-FET 15 in the shift ECU 2 from the first terminal 3b at time t7, whereby the shift ECU 2 The second MOS-FET 15 is turned off (see FIG. 6E). As a result, the voltage Vc at the collector of the NPN transistor 14 (first terminal 2b of the microcomputer 10) rises to a normal high level (for example, 14V) after time t5. Then, the voltage Vb at the power supply output terminal 12c of the power supply circuit 12 decreases and drops to 0V after time t7 (see FIG. 6C). In addition, the voltage at the power supply terminal 2a of the shift ECU 2 and the voltage Va input to the “+” input terminal of the comparator 30 also decrease and decrease to 0V after time t7 (see FIGS. 6A and 6B). ).

  In the present embodiment having such a configuration, the shift ECU 2 has an NPN transistor 14 that cuts off the LED 9 that is a load other than the drive motor 8 that switches the shift range of the transmission, and an upstream terminal of the NPN transistor 14. And a power connection line 31 that connects the second terminal 2c to the power terminal 2a of the shift ECU 2. Then, the second MOS-FET 15 is provided in the power supply connection line 31, and when the second MOS-FET 15 is turned on, the second terminal 2c is connected to the power supply terminal 2a, and the second MOS-FET 15 is turned off. In this case, the second terminal 2c is not connected to the power supply terminal 2a. According to this configuration, when the normal power supply line 6 is disconnected, when the disconnection is detected, the NPN transistor 14 is turned off and the second MOS-FET 15 is turned on. Power can be supplied to the shift ECU 2 via 31. Therefore, by controlling the energization of the drive motor 8, the shift range of the transmission can be switched to the P range which is a predetermined position, so that safety can be improved. And in this embodiment, since it is not necessary to prepare the harness for backup power supplies, manufacturing cost can be suppressed.

  In the present embodiment, since the second MOS-FET 15 is configured to be turned on / off by the ECU 3 other than the shift ECU 2, when the power source of the shift ECU 2 fails and becomes uncontrollable, the other ECU 3 By turning on the second MOS-FET 15, power can be supplied to the shift ECU 2 and necessary measures can be taken. Then, after the necessary measures are completed, the power supply to the shift ECU 2 can be stopped by turning off the second MOS-FET 15 by another ECU 3.

  In the present embodiment, when the normal power supply line 6 is disconnected, power can be supplied to the shift ECU 2 via the power connection line 31, but the amount of current that can be supplied for supply through the load (LED 9). There are limitations. Therefore, in the present embodiment, when the second MOS-FET 15 is turned on, the function not related to the shift range switching of the transmission is stopped, and the function unnecessary for the shift range switching is provided. By cutting the current amount, the shift range can be sufficiently switched.

  In the above embodiment, the second MOS-FET 15 is controlled to be turned on / off by the ECU 3 other than the shift ECU 2. However, the present invention is not limited to this, and the second MOS-FET 15 is connected to the shift ECU 2 (the microcomputer of the shift ECU 2). The on / off control may be performed according to 10). In the case of such a configuration, CAN communication is not necessary, but the power is supplied so that the microcomputer 10 can operate from the occurrence of the disconnection of the power supply line 6 to the completion of turning on the second MOS-FET 15 by the microcomputer 10. The capacitance of the capacitors 22 and 23 of the power supply circuit 12 may be set to a size necessary for holding the power supply.

  In the drawings, 1 is a shift control system, 2 is a shift ECU (shift control device), 3 is an ECU, 4 is a battery, 5 is a power supply line, 6 is a power supply line, 7 is a power supply line, and 8 is a drive motor (drive). Source), 9 LED (load), 10 microcomputer, 11 CAN circuit, 12 power circuit, 13 first MOS-FET, 14 NPN transistor (switch), 15 second MOS-FET ( 17 is a power generation circuit, 18 is a disconnection detection circuit, and 30 is a comparator.

Claims (3)

A shift control device (2) for switching a shift range of a transmission by a shift-by-wire method,
A switch (14) for cutting off the load (9) other than the drive source (8) for switching the shift range of the transmission;
A power connection line (31) for connecting an upstream terminal (2c) of the switch (14) to a power terminal (2a) of the transmission control device (2);
A state in which the upstream terminal (2c) is connected to the power terminal (2a) and a state in which the upstream terminal (2c) is not connected to the power terminal (2a). A shift control device comprising a changeover switch (15) for switching.   The gear change control device according to claim 1, wherein the change-over switch (15) is configured to be turned on and off by an electronic control device (3) other than the gear change control device (2). The speed change control device according to claim 1 or 2, wherein when the changeover switch (15) is turned on, a function not related to the change of the shift range of the transmission is stopped.

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