JP6866503B2 - Electronic control device and exhaust brake control device - Google Patents

Description

The present invention relates to an electronic control device and an exhaust brake control device, and is particularly suitable for application to a vehicle equipped with a diesel engine.

Generally, a large vehicle equipped with a diesel engine has an exhaust flap in the exhaust pipe. The exhaust flap operates in an open position where the exhaust pipe is opened or a closed position where the exhaust pipe is closed under the control of an electronic control unit (ECU).

When the exhaust flap operates in a closed position that closes the exhaust pipe, the exhaust pressure in the exhaust pipe increases, which increases the rotational resistance of the engine and improves the action of the engine brake. A brake that closes the exhaust flap to improve the action of the engine brake is generally called an exhaust brake.

Patent Document 1 discloses a technique relating to an exhaust brake. Specifically, an exhaust brake that secures a constant exhaust flow rate even when the exhaust flap is in the fully closed position by forming a hole in the butterfly valve (exhaust flap) is disclosed. According to the technique described in Patent Document 1, it is possible to reduce the cost required for controlling the exhaust flow rate.

Japanese Unexamined Patent Publication No. 2011-69321

By the way, the exhaust flap is not well recognized as a component that should ensure the safety of vehicle operation. For example, when the exhaust flap unintentionally operates in the fully closed position due to a failure of the ECU, the action of the engine brake is too effective, and sudden deceleration or slip occurs depending on the condition of the road surface. Therefore, there arises a problem that the safety of the vehicle is lowered.

The present invention has been made in consideration of the above points, and proposes an electronic control device and an exhaust brake control device that can ensure the safety of operation of the exhaust flap and improve the safety of the vehicle.

In order to solve such a problem, in the present invention, the electronic control device (30) provided in the vehicle (1), the electronic control device (30) is a CPU (31) and an exhaust flap (19). A relay control unit that controls the operation of the exhaust flap control unit (32) that controls the opening / closing operation of the above, and the relay (50) that is arranged between the exhaust flap (19) and the exhaust flap control unit (32). The exhaust flap control unit (32) includes the exhaust flap (19) based on the instruction signal (S1a) transmitted from the CPU (31) to the exhaust flap control unit (32). A control signal (S1) for operating or maintaining the closed position is generated and transmitted to the exhaust flap (19) via the relay (50), and the relay control unit (40) uses the ABS. or by ESP, if the slip of the vehicle (1) is detected, based on an instruction signal transmitted from said CPU (31) the relay control unit to (40) (S3a), the control relay (50) The relay (50) is operated by transmitting the cutoff signal (S3) to block the control signal (S1) transmitted from the exhaust flap control unit (32) to the exhaust flap (19). It is characterized by that.

According to the present invention, it is possible to ensure the safety of the operation of the exhaust flap and improve the safety of the vehicle.

It is an overall block diagram of the intake system and the exhaust system of a vehicle. It is an internal block diagram of an exhaust brake control device. It is an internal block diagram of another exhaust brake control device. It is an internal block diagram of another exhaust brake control device. It is a flowchart of an exhaust flap control process.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. The following description is merely an embodiment of the present invention, and the technical scope of the present invention is not limited thereto.

FIG. 1 shows the overall configuration of the intake system and the exhaust system of the vehicle 1.
The intake system includes an intake pipe 11, a compressor 12a, an intercooler 13, and an intake manifold 14. The intake air i passes through the intake pipe 11, is compressed by the compressor 12a, is cooled by the intercooler 13, and is distributed to each cylinder by the intake manifold 14. The intake air i distributed to each cylinder is mixed with the fuel injected from the injector 15 and burned in the combustion chamber of each cylinder.

The exhaust system includes an exhaust manifold 16, an exhaust pipe 17, an exhaust gas recirculation (EGR) device 18, a turbine 12b, an exhaust flap 19, and an exhaust purification device 20. The exhaust e discharged from the combustion chamber of each cylinder is integrated by the exhaust manifold 16 and then branched into an exhaust flowing in the direction of the EGR device 18 and an exhaust flowing in the direction of the turbine 12b through the exhaust pipe 17.

The exhaust e flowing in the direction of the EGR device 18 is cooled by the EGR cooler 18b through the EGR pipe 18a, the flow rate is adjusted by the EGR valve 18c, and the exhaust e is distributed to each cylinder again by the intake manifold 14. The exhaust e distributed to each cylinder is reused for combustion.

On the other hand, the exhaust e that is not reused for combustion flows in the direction of the turbine 12b. The exhaust e rotationally drives the compressor 12a connected to the turbine 12b via the turbine 12b. As a result of the intake air i being compressed by the rotational drive of the compressor 12a, combustion in the combustion chamber is promoted. The compressor 12a and the turbine 12b are generally referred to as a turbocharger 12.

The flow rate of the exhaust e that has passed through the turbine 12b is adjusted by the exhaust flap 19. The details of the operation of the exhaust flap 19 will be described later, but it normally operates in the open position and operates in the closed position when the exhaust brake is operated. The exhaust e whose flow rate is adjusted by the exhaust flap 19 passes through the exhaust purification device 20 and is then discharged to the outside.

The exhaust gas purification device 20 includes a DPF (Diesel Particulate Filter) device 20a and a urea SCR (Selective Catalytic Reduction) device 20b. The DPF device 20a collects and removes particulate matter contained in the exhaust gas e. The urea SCR device 20b uses an aqueous urea solution to reduce nitrogen oxides contained in the exhaust gas e to nitrogen or water vapor that is harmless to the human body.

Further, the vehicle 1 includes an exhaust brake control device 100.
The exhaust brake control device 100 includes an electronic control unit (ECU) 30, a relay control unit 40, a relay 50, and an exhaust flap 19.

Although it is shown here that the relay control unit 40 is provided inside the ECU 30 (FIGS. 1 and 2A), the present invention is not limited to this, and the relay control unit 40 is provided inside a device different from the ECU 30. (Fig. 2B, Fig. 2C). For example, the relay control unit 40 may be provided inside an ABS (Antilock Brake System) device or an ESP (Electronic Stability Control) device, which is a device different from the ECU 30.

The ECU 30 receives signals from various sensors (not shown) installed in each part of the vehicle 1 and transmits control signals to various devices (not shown) installed in each part of the vehicle 1. The operation of the vehicle 1 is comprehensively controlled.

In particular, here, the ECU 30 transmits the control signal S1 to the actuator (not shown) that operates the exhaust flap 19 via the relay 50. As a result, the ECU 30 can operate the exhaust flap 19 in the open position in the closed position during the exhaust brake operation. The closed position includes an intermediate position in which the exhaust pipe 17 is partially closed and a fully closed position in which the entire exhaust pipe 17 is closed.

The exhaust flap 19 is provided with a spring member such as a return spring (not shown), and normally maintains the open position by the action of the spring force of the return spring when the control signal S1 is not transmitted. On the other hand, the exhaust flap 19 operates in the closed position contrary to the spring force of the return spring during the exhaust brake operation in which the control signal S1 is transmitted.

Further, the exhaust flap 19 includes a position sensor (not shown) and transmits a position signal S2 indicating an open position or a closed position to the ECU 30. The ECU 30 appropriately controls the operation of the exhaust flap 19 based on the position signal S2.

The relay control unit 40 is configured to be stored in a circuit different from the circuit that generates or transmits the control signal S1 or a device (ABS, ESP, etc.) physically different from the ECU 30. Further, the relay control unit 40 controls the operation of the relay 50 by using an independent signal line different from the signal line to which the control signal S1 is transmitted.

Specifically, when a sudden deceleration or slip is detected, the relay control unit 40 transmits a cutoff signal S3 to the relay 50 and cuts off the control signal S1 from the ECU 30. As a result, the exhaust flap 19 operates in the open position by the action of the spring force of the return spring.

On the other hand, in the normal time when sudden deceleration or slip is not detected, the relay control unit 40 conducts the signal line connecting the ECU 30 and the exhaust flap 19 without transmitting the cutoff signal S3. That is, the exhaust flap 19 maintains the closed position when receiving the control signal S1 from the ECU 30, and maintains the open position when it does not receive the control signal S1.

The relay control unit 40 may transmit a cutoff signal S3 when receiving a detection signal from an external device such as ABS or ESP that detects deceleration or slip, or the relay control unit 40 itself may suddenly decelerate or slip. The cutoff signal S3 may be transmitted when the above is detected.

The relay 50 is arranged between the ECU 30 and the exhaust flap 19, and connects the ECU 30 and the exhaust flap 19 so as to be communicable. Further, the relay 50 is connected to the relay control unit 40 by a signal line different from the signal line between the ECU 30 and the exhaust flap 19. The relay 50 operates so as to conduct the signal line at normal times and cut off the signal line at the time of sudden deceleration or slip under the control of the relay control unit 40.

FIG. 2A shows the internal configuration of the exhaust brake control device 100.
As described above, the exhaust brake control device 100 includes an ECU 30, a relay 50, and an exhaust flap 19. The ECU 30 includes a CPU (Central Processing Unit) 31, an H-bridge circuit 32, and a relay control unit 40.

The CPU 31 comprehensively controls the operation of the ECU 30. Here, in order to control the operation of the exhaust flap 19, the CPU 31 receives the position signal S2 from the exhaust flap 19, and when the opening / closing position of the exhaust flap 19 should be controlled based on the position signal S2, the H-bridge circuit 32 and The instruction signals S1A and S3A are transmitted to the relay control unit 40.

The H-bridge circuit 32 functions as an exhaust flap control unit, and transmits a control signal S1 for controlling the opening / closing position of the exhaust flap 19 based on the instruction signal S1A from the CPU 31. The control signal S1 is transmitted to the actuator (not shown) via the relay 50. The actuator is operated to the closed position when the exhaust flap 19 is in the open position based on the control signal S1.

The relay control unit 40 transmits a cutoff signal S3 that controls the operation of the relay 50 based on the instruction signal S3A from the CPU 31. When the relay 50 receives the cutoff signal S3, the relay 50 cuts off the signal line connecting the ECU 30 and the exhaust flap 19 regardless of whether or not the control signal S1 is transmitted, thereby cutting off the control signal from the H-bridge circuit 32. Block S1.

Actually, the relay control unit 40 is, for example, a low-side switch. When the low side switch receives the instruction signal S3A from the CPU 31, it switches to ON. In this case, one end of the coil of the relay 50 is connected to the CPU 31 via the H-bridge circuit 32, and the other end of the coil is connected to the low-side switch. Therefore, when the low-side switch is switched to ON, the relay 50 Current flows through the coil.

As a result, a current path is formed (CPU 31, H-bridge circuit 32, relay 50, low-side switch, CPU 31), and when a current flows through the coil of the relay 50, the relay 50 operates and the control signal S1 can be cut off.

FIG. 2B shows the internal configuration of another exhaust brake control device 100B.
The other exhaust brake control device 100B is different from the exhaust brake control device 100 of FIG. 2A in that it includes an external ECU 60 having a housing separate from the ECU 30 and a relay control unit 40 inside the external ECU 60.

Hereinafter, only the different points will be described, and the same components as those of the exhaust brake control device 100 of FIG. 2A will be designated by the same reference numerals and description thereof will be omitted.

The external ECU 60 is an ECU that detects a sudden deceleration or slip of the vehicle 1, and is, for example, ABS or ESP. When the CPU 61 of the external ECU 60 detects a sudden deceleration or slip of the vehicle 1, it transmits an instruction signal S3A to the relay control unit 40.

When the relay control unit 40 receives the instruction signal S3A, as described above, the relay control unit 40 transmits a cutoff signal S3 that controls the operation of the relay 50, and cuts off the control signal S1 from the ECU 30 (H bridge circuit 32).

Actually, a battery (not shown) is connected to one end of the coil of the relay 50. On the other hand, the other end of the coil is connected to the relay control unit 40, and when the relay control unit 40 receives the instruction signal S3A from the CPU 61, it operates so as to conduct conduction.

As a result, a current path is formed (battery, relay 50, relay control unit 40, CPU 61), and a current flows through the coil of the relay 50. In this case, the relay 50 can operate to cut off the control signal S1.

FIG. 2C shows the internal configuration of another exhaust brake control device 100C.
The other exhaust brake control device 100C is different from the exhaust brake control device 100 of FIG. 2A in that it includes an external ECU 60 having a housing separate from the ECU 30 and a relay control unit 40 inside the external ECU 60.

Further, the ECU 30 is different from the other exhaust brake control device 100B in FIG. 2B in that the ECU 30 includes a high side switch 33 and a low side switch 34 instead of the H bridge circuit 32.

Hereinafter, only the different points will be described, and the same reference numerals will be given to the same configurations as the exhaust brake control devices 100 and 100B of FIGS. 2A and 2B, and the description thereof will be omitted.

In order to control the operation of the exhaust flap 19, the CPU 31 of the ECU 30 transmits an instruction signal S1A to the high side switch 33 and the low side switch 34 when the opening / closing position of the exhaust flap 19 should be controlled.

The high-side switch 33 and the low-side switch 34 are switched to ON when the instruction signal S1A is received. As a result, the high-side switch 33 and the low-side switch 34 transmit the control signal S1 to the exhaust flap 19.

When the relay control unit 40 receives the instruction signal S3A, as described above, the relay control unit 40 transmits a cutoff signal S3 that controls the operation of the relay 50, and cuts off the control signal S1 from the ECU 30 (low side switch 34).

Although the relay 50 is arranged between the low side switch 34 and the exhaust flap 19 here, the present invention is not limited to this, and the relay 50 may be arranged between the high side switch 33 and the exhaust flap 19.

FIG. 3 shows a flowchart of the exhaust flap control process. The exhaust flap control process is executed by the ECU 30 (CPU 31) of the exhaust brake control device 100. It is also executed as appropriate when the exhaust brake is operated.

First, when operating the exhaust brake, the ECU 30 transmits a control signal S1 to the actuator of the exhaust flap 19 to operate the exhaust flap 19 in the closed position (SP1).

Next, the ECU 30 determines whether or not a sudden deceleration or slip of the vehicle 1 has been detected (SP2). As a method for the ECU 30 to detect deceleration or slip, for example, there is a method for receiving and detecting a detection signal from ABS that detects deceleration or slip.

When the ECU 30 obtains a negative result in the judgment of step SP2 (SP2: N), the ECU 30 shifts to step SP4. On the other hand, when the ECU 30 obtains an affirmative result in the determination of step SP2 (SP2: Y), the ECU 30 determines whether or not the detected deceleration or slip amount is equal to or greater than a predetermined value (SP3).

When the ECU 30 obtains a negative result in the judgment of step SP3 (SP3: N), the ECU 30 shifts to step SP1 and repeats the above process. On the other hand, when the ECU 30 obtains an affirmative result in the judgment of step SP3 (SP3: Y), the relay control unit 40 operates the relay 50 to shut off the control signal S1 transmitted from the ECU 30 to the exhaust flap 19 (SP3: Y). SP4).

Next, the ECU 30 determines whether or not the position of the exhaust flap 19 is an open position based on the position signal S2 from the exhaust flap 19 (SP5).

When the ECU 30 obtains a negative result in the judgment of step SP5 (SP5: N), it determines that the exhaust flap 19 is still in the closed position even if the control signal S1 is cut off, and the ECU 30 or the exhaust flap is in an abnormal state. Notify 19 defects (SP6) and end this process.

On the other hand, when the ECU 30 obtains an affirmative result in the judgment of step SP5 (SP5: Y), the ECU 30 terminates this process assuming that the safety of the operation of the exhaust flap 19 is ensured.

The exhaust flap control process described above is similarly executed in the other exhaust brake control devices 100B and 100C. In this case, the processing content or processing entity in each step is partially different. For example, when the ECU 30 transmits the control signal S1 to the exhaust flap 19 in step SP1, when the external ECU 60 detects deceleration or slip in step SP2, the process proceeds to step SP4 and the external ECU 60 operates the relay 50. , The control signal S1 may be forcibly cut off.

As described above, according to the present embodiment, the H-bridge circuit 32, the high-side switch 33 or the low-side switch 34 is provided as the exhaust flap control unit that controls the opening / closing operation of the exhaust flap 19, and these H-bridge circuits 32 and the high-side are provided. The relay control unit 40 is provided as a circuit different from the switch 33 or the low side switch 34.

Then, the relay control unit 40 independently controls the operation of the relay 50 arranged between the ECU 30 and the exhaust flap 19, so that the H bridge circuit 32, the high side switch 33 or the low side switch 34 is transferred to the exhaust flap 19. The control signal S1 transmitted to the control signal S1 can be blocked.

As a result, when a sudden deceleration or slip of the vehicle 1 is detected, the control signal S1 transmitted from the ECU 30 can be forcibly cut off. In this case, it is possible to prevent the exhaust flap 19 from being unintentionally maintained in the closed position due to a failure of the ECU 30, and to ensure the safety of the operation of the exhaust flap 19. Therefore, the safety of the vehicle can be improved.

Claims (4)

An electronic control device (30) provided in the vehicle (1).
The electronic control device (30)
CPU (31) and
An exhaust flap control unit (32) that controls the opening / closing operation of the exhaust flap (19),
A relay control unit (40) for controlling the operation of a relay (50) arranged between the exhaust flap (19) and the exhaust flap control unit (32) is provided.
The exhaust flap control unit (32) operates or closes the exhaust flap (19) in a closed position based on an instruction signal (S1a) transmitted from the CPU (31) to the exhaust flap control unit (32). A control signal (S1) for maintaining the position is generated and transmitted to the exhaust flap (19) via the relay (50).
The relay control unit (40), the ABS or ESP, if the slip of the vehicle (1) is detected, an instruction signal transmitted from said CPU (31) the relay control unit to (40) (S3a) By transmitting a cutoff signal (S3) for controlling the relay (50), the relay (50) is operated and transmitted from the exhaust flap control unit (32) to the exhaust flap (19). An electronic control device (30) characterized by blocking a control signal (S1) to be generated. The relay control unit (40)
The relay (50) is operated by using an independent signal line different from the signal line connecting the exhaust flap control unit (32) and the exhaust flap (19), and the exhaust flap control unit (32) is operated. The electronic control device (30) according to claim 1 , wherein the control signal (S1) from the) is blocked. The relay control unit (40)
The electronic control device (30) according to claim 1 or 2 , wherein the circuit is separate from the exhaust flap control unit (32). Exhaust flap (19) and
An exhaust flap control unit (32) that controls the opening / closing operation of the exhaust flap (19),
A relay (50) arranged between the exhaust flap (19) and the exhaust flap control unit (32),
A relay control unit (40) that controls the operation of the relay (50) ,
CPU (31) and
An electronic control device (30) including the CPU, the exhaust flap control unit (32), and the relay control unit (40).
A Ru equipped with an exhaust brake control device (100),
The exhaust flap control unit (32) operates or closes the exhaust flap (19) in a closed position based on an instruction signal (S1a) transmitted from the CPU (31) to the exhaust flap control unit (32). A control signal (S1) for maintaining the position is generated and transmitted to the exhaust flap (19) via the relay (50).
The relay control unit (40), the ABS or ESP, the exhaust brake control device (100) the vehicle comprises (1) if the slip is detected, wherein the relay control unit from CPU (31) to (40) The relay (50) is operated by transmitting a cutoff signal (S3) for controlling the relay (50) based on the transmitted instruction signal (S3a), and the exhaust is exhausted from the exhaust flap control unit (32). An exhaust brake control device (100) characterized by blocking a control signal (S1) transmitted to a flap (19).

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