JP2006266180A - Exhaust brake device for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an exhaust brake device for a vehicle preventing generation of noise at a time of exhaust brake operation. <P>SOLUTION: In an invention concerning claim 1, the exhaust brake for the vehicle provided with an exhaust gas shutter installed in an exhaust gas passage of an engine and an actuator driving the exhaust gas shutter open and close variably control length of exhaust gas passage from the engine to the exhaust gas shutter according to engine rotation speed at a time of exhaust brake operation. In an invention concerning claim 2, the exhaust brake device for the vehicle described in claim 1is provided with bypass passages of different length of exhaust gas passage in an exhaust gas upstream side exhaust gas passage of the exhaust gas shutter, and a change over valve operated by an actuator to change over both passage is installed at a branch part of the both passage. The change over valve is controlled to change over according to engine rotation speed at a time of exhaust brake operation. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an exhaust brake device for a vehicle.

There is no particulate or black smoke emission, and NOx (nitrogen oxide) can be reduced compared to diesel engines. Today, compressed natural gas engines using compressed natural gas (hereinafter referred to as “CNG engine”) Widely used in trucks and buses.
And as disclosed in Patent Document 1, conventionally, exhaust brake devices are widely used as auxiliary brake devices for foot brakes in vehicles such as trucks and buses equipped with diesel engines, but they are equipped with CNG engines. This exhaust brake device is also used in vehicles such as trucks.

In general, this exhaust brake device includes an exhaust shutter mounted in an exhaust pipe (exhaust passage) and an actuator that opens and closes the exhaust shutter, and the exhaust shutter is closed by the actuator during deceleration (closes the exhaust passage). Thus, when the exhaust shutter is closed, the pressure in the exhaust pipe increases, and this pressure acts as a force that pushes back the piston during the exhaust stroke. The traveling speed will be reduced.
Japanese Utility Model Publication No. 5-36045

However, in a vehicle equipped with the exhaust brake device as described above, when the exhaust brake is operated in a high engine speed range (for example, 2000 revolutions or more with a CNG engine), the exhaust pipe on the exhaust gas upstream side of the exhaust shutter There was a problem that an abnormal noise was generated, causing the driver to feel uncomfortable.
That is, as is well known in the art, engine piping (exhaust pipes and intake pipes) has the natural frequency of the air column corresponding to its length.

For this reason, it is considered that when the exhaust brake is operated, the frequency of the exhaust pulsation of the engine and the air column vibration of the exhaust pipe are synchronized (resonated), and abnormal noise is generated. The noise tends to decrease when the sound is loud and the engine speed is low.
The present invention has been devised in view of such circumstances, and an object of the present invention is to provide an exhaust brake device that prevents generation of abnormal noise when the exhaust brake is operated.

In order to achieve such an object, an invention according to claim 1 is directed to an exhaust brake device for a vehicle including an exhaust shutter mounted in an exhaust passage of an engine and an actuator for opening and closing the exhaust shutter. The exhaust passage length from the engine to the exhaust shutter is variably controlled according to the engine speed when the exhaust brake is operated.
According to a second aspect of the present invention, in the exhaust brake device according to the first aspect, a bypass passage having a different exhaust passage length is provided in the exhaust passage on the exhaust gas upstream side of the exhaust shutter, and a branch portion of both passages is provided. In addition, a switching valve that is operated by an actuator to switch both passages is mounted, and the switching valve is switched and controlled according to the engine speed when the exhaust brake is operated.

Furthermore, the invention according to claim 3 is the exhaust brake device according to claim 1, wherein a second exhaust shutter driven to open and close by an actuator is mounted in the exhaust passage upstream of the exhaust shutter. When the exhaust brake is operated, both exhaust shutters are driven and controlled according to the engine speed.
According to a fourth aspect of the present invention, there is provided an exhaust brake device for a vehicle including an exhaust shutter mounted in an exhaust passage of an engine and an actuator for opening and closing the exhaust shutter. A resonator chamber is provided in the exhaust passage on the side, and the invention according to claim 5 is a vehicle provided with an exhaust shutter mounted in the exhaust passage of the engine and an actuator for driving the exhaust shutter to open and close In the exhaust brake device, the opening degree of the exhaust shutter is controlled according to the engine speed when the exhaust brake is operated.

According to the first to third aspects of the invention, when the exhaust brake is operated, the resonance vibration frequency is controlled by variably controlling the exhaust passage length from the engine to the exhaust shutter according to the engine speed. It became possible to prevent the occurrence of abnormal noise at the time.
Further, according to the invention according to claim 4, it is possible to prevent the generation of the abnormal noise by attenuating the noise of the specific center frequency generated when the exhaust brake is operated in the resonator chamber, and according to the invention according to claim 5. By controlling the opening degree of the exhaust shutter according to the engine speed, the amplitude of the standing wave generated in the exhaust pipe changes and the resonance frequency changes, so that the generation of abnormal noise can be prevented. .

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 shows an intake / exhaust system of a CNG engine equipped with an exhaust brake device according to one embodiment of the present invention. In the figure, reference numeral 1 denotes a CNG engine using compressed natural gas as a fuel, and a cylinder head 3. A branch pipe of the intake manifold 5 is connected to each intake port of each cylinder, and a branch pipe of the exhaust manifold 7 is connected to each exhaust port of each cylinder.

  Although not shown, the ECU is suitable for driving conditions based on detection values of a crank angle sensor (engine speed detection sensor) attached to the CNG engine 1 and a boost pressure sensor (intake pressure detection sensor) attached to the intake manifold 5. The fuel injection amount is obtained, and the CNG fuel is injected by the fuel injection nozzle 17 into the intake passage 15 in the intake pipe 13 in order from each injector 11 of the multiple injector 9. CNG fuel is supplied to each cylinder.

  A turbocharger 21 is attached to an exhaust pipe 19 connected to the exhaust manifold 7. When the exhaust gas G discharged from the CNG engine 1 rotates the turbine 22 of the turbocharger 21, the compressor rotates directly connected to the turbocharger 21. 23 compresses the intake air A, and the supercharged compressed air A-1 is sent to the CNG engine 1 from the intake passage 15 via the intake manifold 5.

  Furthermore, an intercooler 25 that lowers the temperature of the compressed air A-1 supercharged by the turbocharger 21 to improve the charging efficiency of the intake air is attached to the intake pipe 13 and the intake air on the upstream side of the compressor 23 is installed. An air filter 27 is attached to the passage 11, and a silencer 33 incorporating a catalyst 31 is attached to an exhaust pipe 29 connected to the turbine 22. A throttle valve 35 is mounted in the intake passage 15 between the intercooler 25 and the intake manifold 5, and the single-hole nozzle type fuel injection nozzle 17 is disposed on the exhaust gas upstream side of the throttle valve 35 in the direction opposite to the flow of intake air. Is attached, and the multiple injector 9 is connected to the fuel injection nozzle 17.

As shown in FIG. 1, an exhaust brake device 37 according to this embodiment is attached to the exhaust pipe 29.
In FIG. 1, reference numeral 39 denotes an exhaust shutter (butterfly valve) that opens and closes an exhaust passage 41 on the exhaust gas upstream side of the silencer 33. The exhaust shutter 39 is mounted in the vicinity of the silencer 33. A single-action piston type air cylinder (actuator) 43 is connected to the exhaust shutter 39, and an air tank 47 is connected to the air cylinder 43 via an air pipe 45.

The air pipe 45 is equipped with an electromagnetic valve 49 controlled by the ECU. As in the case of a conventional exhaust brake device, the air cylinder 43 is controlled by the ECU when the exhaust brake is operated. 39 is closed to close the exhaust passage 41.
As in the prior art, when the driver turns on an exhaust brake hand switch (not shown), the ECU sends an exhaust brake activation signal to the electromagnetic valve 49 to activate it when the clutch is engaged and the transmission is not in the neutral position. Hereinafter, in the present specification, “operation of the exhaust brake” refers to such a series of operations.

Thus, when the exhaust shutter 39 is closed as described above, the pressure in the exhaust passage 41 increases, and this pressure becomes a braking force to decelerate the vehicle. However, the exhaust brake device 37 according to this embodiment is described above. In addition to the same configuration as in the prior art, it has the following characteristics.
That is, the exhaust passage 41 (exhaust pipe 29) on the exhaust gas upstream side of the exhaust shutter 39 is provided with a bypass passage 51 having a longer exhaust passage length than the exhaust passage 41 directly below the exhaust pipe 29.

A switching valve 55 for switching the flow path between the exhaust passage 41 and the bypass passage 51 by being opened and closed by a single-acting piston type air cylinder 53 is mounted at a branch portion between the exhaust passage 41 and the bypass passage 51. An air pipe 57 is connected between the cylinder 53 and the air tank 47, and an electromagnetic valve 59 controlled by the ECU is attached to the air pipe 57.
Thus, as described above, conventionally, in a vehicle equipped with an exhaust brake device, when the exhaust brake is operated in a high engine speed range, the exhaust pulsation and the exhaust column air column vibration are synchronized with each other. There is a problem that sounds are generated.

Therefore, in the present embodiment, the engine speed in the high engine speed range where abnormal noise starts to occur when the exhaust brake is operated is set and stored in advance in the ECU memory as the set value N.
Then, the ECU compares the detected value Ni of the engine speed detected by the crank angle sensor with the set value N when the exhaust brake that drives the air cylinder 43 to close the exhaust shutter 39 is operated, and detects the detected value Ni. Is determined to be greater than or equal to the set value N, a command is sent to the electromagnetic valve 59, the switching valve 55 is operated by the air cylinder 53 to close the flow path on the exhaust passage 41 side, and the bypass passage 51 side is opened to release the exhaust gas G. It is made to flow down to the bypass passage 51.

Thus, in the present embodiment, when the engine speed of the CNG engine 1 is equal to or higher than the set value N when the exhaust brake is operated, the switching valve 55 closes the flow path on the exhaust passage 41 side and opens the bypass passage 51 side. By increasing the length of the exhaust passage from the CNG engine 1 to the exhaust shutter 39, the resonance vibration frequency is shifted to the low rotation side.
In addition, when the vehicle decelerates due to the operation of the exhaust brake and the engine speed decreases while the resonance vibration frequency is shifted to the low rotation side in this manner, the exhaust gas is exhausted in the low rotation range of the CNG engine 1 during the operation of the exhaust brake. The pulsation and air column vibration are synchronized with each other, and there is a possibility that abnormal noise is generated again.

Therefore, when the detected value Ni of the engine speed falls below the set value N, the ECU closes the bypass passage 51 side with the switching valve 55 via the air cylinder 53 in order to prevent such abnormal noise from being generated. The side of the passage 41 is opened so that the exhaust gas G flows down to the exhaust passage 41.
When the exhaust brake is not operated, the switching valve 55 closes the bypass passage 51 side and opens the exhaust passage 41 side from the low rotation range to the high rotation range of the CNG engine 1 to pass the exhaust gas G to the exhaust passage 41. It is flowing down.

FIG. 2 illustrates the relationship between the engine speed during the operation of the exhaust brake and the switching of the flow path by the switching valve 55.
Since the present embodiment is configured in this way, the ECU detects the engine speed from the crank angle sensor when the exhaust brake is operated to drive the air cylinder 43 and close the exhaust shutter 39 (see FIG. 3). In step S1, the detected value Ni is compared with the set value N (step S2).

If it is determined in step S2 that the detected value Ni is greater than or equal to the set value N, the process proceeds to step S3, where the ECU sends a command to the electromagnetic valve 59, and operates the switching valve 55 by the air cylinder 53 to exhaust the exhaust passage. The flow path on the 41 side is closed and the bypass passage 51 side is opened to let the exhaust gas G flow down to the bypass passage 51.
Thus, the exhaust passage 41 from the CNG engine 1 to the exhaust shutter 39 is lengthened by closing the exhaust passage 41 side flow path and opening the bypass passage 51 side flow path. Resonance vibration frequency shifts to the low rotation side, resonance is prevented, and no abnormal noise is generated.

Further, even if the exhaust gas G is bypassed to the bypass passage 51 side having a long exhaust passage length, the exhaust gas temperature is high in the high rotation region of the CNG engine 1, and therefore the catalyst 31 is compared with the case of flowing down the exhaust passage 41 side. Although there is a large temperature drop until this time, the catalyst activity is not hindered.
On the other hand, if it is determined in step S2 that the detected value Ni has not reached the set value N, the ECU proceeds to step S4, opens the flow passage on the exhaust passage 41 side, closes the bypass passage 51 side, and closes the exhaust gas G. Is caused to flow down to the exhaust passage 41.

  As described above, when the exhaust brake is not operated, the switching valve 55 closes the bypass passage 51 side and opens the exhaust passage 41 side from the low rotation region to the high rotation region of the CNG engine 1. When it is determined in step S2 that the detected value Ni has not reached the set value N, the ECU again closes the bypass passage 51 side by the switching valve 55 and does not open the exhaust passage 41 side.

Thus, since the exhaust gas temperature is often low in the low rotation region of the CNG engine 1, the exhaust gas G flows down on the exhaust passage 41 side having a short flow path in this way, so that the exhaust gas temperature reaches the catalyst 31. It is difficult to descend and is convenient.
Thus, in the present embodiment, when the engine speed of the CNG engine 1 is equal to or higher than the set value N when the exhaust brake is operated, the switching valve 55 closes the flow path on the exhaust passage 41 side and opens the bypass passage 51 side. Since the resonance vibration frequency is shifted to the low rotation side by increasing the length of the exhaust passage from the CNG engine 1 to the exhaust shutter 39, it is possible to prevent noise generation in the high engine speed range when the exhaust brake is operated. It became.

FIG. 4 shows an intake / exhaust system of a CNG engine equipped with an exhaust brake device according to one embodiment of claims 1 and 3, and this embodiment replaces the exhaust brake device 37 of FIG. The first and second exhaust shutters are mounted on the exhaust gas upstream side and the exhaust gas downstream side to prevent the generation of noise during the operation of the exhaust brake.
Hereinafter, the present embodiment will be described with reference to FIG. 4, but the same components as those in the embodiment of FIG.

  In FIG. 4, reference numeral 61 denotes a first exhaust shutter (butterfly valve) mounted in the exhaust passage 41. Like the exhaust shutter 39 described above, a single-acting piston type air cylinder (actuator) is connected to the exhaust shutter 61. 63 is connected, and an air tank 47 is connected to the air cylinder 63 via an air pipe 65. An electromagnetic valve 67 controlled by the ECU is attached to the air pipe 65.

  In the figure, reference numeral 69 denotes a second exhaust shutter (butterfly valve) mounted in the exhaust passage 41 on the exhaust gas downstream side of the exhaust shutter 61. The exhaust shutter 69 also has a single-acting piston type air cylinder 71. Is connected, and an air tank 47 is connected to the air cylinder 71 via an air pipe 73, and an electromagnetic valve 75 controlled by the ECU is attached to the air pipe 65.

  As in the embodiment of FIG. 1, the engine speed in the high engine speed range where abnormal noise starts to occur when the exhaust brake is operated is preset and stored in the memory as the set value N. When operating the exhaust brake, the detected value Ni of the engine speed detected by the crank angle sensor is compared with the set value N. The air cylinder 63 opens the exhaust shutter 61 and the air cylinder 71 closes the exhaust shutter 69.

If the detected value Ni of the engine speed is lower than the set value N when the exhaust brake is operated, the ECU closes the exhaust shutter 61 with the air cylinder 63 and the exhaust shutter 69 with the air cylinder 71. Is opened.
When the detected value Ni of the engine speed is lower than the set value N, both the exhaust shutters 61 and 69 may be closed.

As described above, the exhaust brake device 77 according to the present embodiment opens the exhaust shutter 61 and closes the exhaust shutter 69 to open the CNG engine when the engine speed is equal to or higher than the set value N when the exhaust brake is operated. By increasing the length of the exhaust passage from 1 to the exhaust shutter 69, the resonance vibration frequency is shifted to the low rotation side to prevent the generation of abnormal noise.
In addition, when the vehicle decelerates due to the operation of the exhaust brake and the engine speed decreases while the resonance vibration frequency is shifted to the low rotation side in this manner, the exhaust gas is exhausted in the low rotation range of the CNG engine 1 during the operation of the exhaust brake. The pulsation and air column vibration are synchronized with each other, and there is a possibility that abnormal noise is generated again.

Therefore, when the detected value Ni of the engine speed falls below the set value N, the ECU operates the exhaust brake by closing the exhaust shutter 61 in order to prevent the generation of such abnormal noise. .
When the exhaust brake is not operated, the exhaust shutters 61 and 69 open the exhaust passage 41 from the low rotation range to the high rotation range of the CNG engine 1.

Since the present embodiment is configured as described above, the ECU detects the engine speed from the crank angle sensor when operating the exhaust brake (step S5 in FIG. 5), and the detected value Ni and the set value N Are compared (step S6).
When it is determined in step S6 that the detected value Ni is greater than or equal to the set value N, the process proceeds to step S7, where the ECU sends a command to the electromagnetic valves 67 and 75 as described above, and the air cylinder 63 performs exhaust. The shutter 61 is opened and the exhaust cylinder 69 is closed by the air cylinder 71.

Thus, since the exhaust shutter 69 on the exhaust gas downstream side is closed in this way, a long exhaust passage from the CNG engine 1 to the second exhaust shutter 69 is obtained, so that the resonance vibration frequency of the air column vibration is low. It will shift to the rotation side.
On the other hand, if it is determined in step S6 that the detected value Ni has not reached the set value N, the ECU proceeds to step S8, and closes the exhaust shutter 61 with the air cylinder 63 and exhausts the shutter 69 with the air cylinder 71. Open. As described above, in this case, both the exhaust shutters 61 and 69 may be closed.

As described above, the exhaust brake device 77 according to the present embodiment is configured to use the first and second exhaust shutters 61 and 69 properly according to the engine speed when the exhaust brake is operated, so that the exhaust passage length is properly used. Also in this embodiment, similar to the exhaust brake device 37 of FIG. 1, it is possible to prevent the generation of abnormal noise in the high engine speed range when the exhaust brake is operated.
FIG. 6 shows an intake / exhaust system of a CNG engine equipped with an exhaust brake device according to an embodiment of claim 4. The exhaust brake device 79 according to this embodiment is a bypass passage in the exhaust brake device 37 of FIG. 51 and a switching valve 55, a resonator chamber 81 is provided in the exhaust passage 41 on the exhaust gas upstream side of the exhaust shutter 39, and this resonator chamber 81 has a specific center frequency of abnormal noise generated in the high engine speed range when the exhaust brake is operated. The sound is attenuated, and the capacity of the resonator chamber 81 and the diameter and size of the neck tube 83 are appropriately set according to specifications.

Thus, according to this embodiment, there is an advantage that the noise of the specific center frequency generated in the high engine speed range when the exhaust brake is operated is attenuated in the resonator chamber 81 and the generation of the abnormal noise can be prevented.
FIG. 7 shows an intake / exhaust system of a CNG engine equipped with an exhaust brake device according to an embodiment of claim 5. The exhaust brake device 85 according to the present embodiment is connected to an exhaust shutter 39 installed in the exhaust passage 41. A dynamic double rod type air cylinder (actuator) 87 is connected, an air tank 47 is connected to the air cylinder 87 via an air pipe 89, and a pressure control valve 93 controlled by the ECU 91 is attached to the air pipe 89. It is. The air cylinder 87 is controlled by a pressure control valve 93 so as to have a plurality of strokes. When the exhaust brake is not operated, the exhaust shutter 39 is connected to the exhaust passage from the low rotation range to the high rotation range of the CNG engine 1. 41 is open.

  Also in the present embodiment, the ECU 91 has the engine speed in the high engine speed range where noise starts to be generated when the exhaust brake is activated set and stored in advance in the memory as the set value N. When the exhaust brake is operated, the detected value Ni of the engine speed detected by the crank angle sensor is compared with the set value N. It is sent to the control valve 93, and the stroke of the air cylinder 87 is reduced to increase the opening degree of the exhaust shutter 39 (make it open slightly; position b in FIG. 7).

Further, when the vehicle decelerates due to the operation of the exhaust brake and the detected value Ni becomes smaller than the set value N, the ECU 91 sends a large duty signal to the pressure control valve 93 to increase the stroke of the air cylinder 87 and exhaust the exhaust gas. The opening degree of the shutter 39 is reduced (closed; position a in FIG. 7).
Further, when the exhaust brake is operated, if it is determined that the detected value Ni is smaller than the set value N, the ECU increases the stroke of the air cylinder 87 from the beginning to reduce the opening of the exhaust shutter 39.

Since other configurations are the same as those of the embodiment of FIG. 1, the same components are denoted by the same reference numerals and description thereof is omitted.
The present embodiment is configured as described above, and as described above, the ECU 91 compares the detected value Ni of the engine speed detected by the crank angle sensor with the set value N when operating the exhaust brake (FIG. 8 step S9).

When it is determined in step S10 that the detected value Ni is greater than or equal to the set value N, the ECU 91 sends a small duty signal to the pressure control valve 93 as described above (step S11). As a result, the air cylinder 87 is small. The opening degree of the exhaust shutter 39 is increased by the stroke (position b in FIG. 7).
Thus, when air column vibration is generated as is well known in the art, a standing wave is generated in the air column. When the exhaust shutter 39 is closed and the exhaust brake is operated as described above, When the shutter 39 is opened like the position b in FIG. 7, the amplitude of the standing wave is extended and the resonance frequency causing the abnormal noise is shifted, so that the conventional abnormal noise is prevented from being generated. .

When the vehicle decelerates and it is determined in step S12 that the detected value Ni has become smaller than the set value N, the ECU 91 sends a large duty signal to the pressure control valve 93 (step S13), and as a result, the stroke of the air cylinder 87. Increases and the opening of the exhaust shutter 39 decreases (position a in FIG. 7).
If it is determined in step S10 that the detected value Ni is smaller than the set value N during the operation of the exhaust brake, the process proceeds to step S13, where the ECU reduces the stroke of the air cylinder 87 from the beginning and sets the exhaust shutter 39. The opening is reduced (position a in FIG. 7).

  As described above, the exhaust brake device 85 according to the present embodiment is configured to variably adjust the amplitude of the standing wave by controlling the opening / closing opening degree of the exhaust shutter 39 according to the engine rotational speed. As in the above-described embodiments, it is possible to prevent the generation of abnormal noise that occurs in the high engine speed range when the exhaust brake is operated.

It is a block diagram of the intake / exhaust system of the CNG engine equipped with the exhaust brake device according to one embodiment of claim 1 and claim 2. It is a relationship diagram of the engine speed at the time of exhaust brake operation, and the switching of the flow path by a switching valve. It is a flowchart which shows the operating state of an exhaust brake device. It is a block diagram of the intake / exhaust system of the CNG engine equipped with the exhaust brake device according to one embodiment of claim 1 and claim 3. It is a flowchart which shows the operating state of an exhaust brake device. It is a block diagram of the intake / exhaust system of the CNG engine equipped with the exhaust brake device according to one embodiment of claim 4. It is a block diagram of the intake / exhaust system of the CNG engine equipped with the exhaust brake device according to one embodiment of claim 5. It is a flowchart which shows the operating state of an exhaust brake device.

Explanation of symbols

1 CNG engine 5 Intake manifold 7 Exhaust manifold 13 Intake pipe 15 Intake passage 19, 29 Exhaust pipe 21 Turbocharger 33 Silencer 37, 77, 79, 85 Exhaust brake device 39, 61, 69 Exhaust shutter 41 Exhaust passage 43, 53, 63, 71, 87 Air cylinder 47 Air tank 49, 59, 67, 75 Electromagnetic valve 51 Bypass passage 55 Switching valve 81 Resonator chamber 91 ECU
93 Pressure control valve

Claims (5)

In an exhaust brake device for a vehicle, comprising an exhaust shutter mounted in an exhaust passage of an engine, and an actuator for opening and closing the exhaust shutter,
An exhaust brake device for a vehicle, wherein the exhaust passage length from the engine to the exhaust shutter is variably controlled according to the engine speed when the exhaust brake is operated. The exhaust passage on the exhaust gas upstream side of the exhaust shutter is provided with a bypass passage having different exhaust passage lengths, and a switching valve that is operated by an actuator and switches between both passages is mounted on a branch portion of both passages.
2. The exhaust brake device for a vehicle according to claim 1, wherein when the exhaust brake is operated, the switching valve is controlled to switch according to the engine speed. A second exhaust shutter that is opened and closed by an actuator is installed in the exhaust passage on the exhaust gas upstream side of the exhaust shutter,
2. The exhaust brake device for a vehicle according to claim 1, wherein when the exhaust brake is operated, both exhaust shutters are driven and controlled according to the engine speed. In an exhaust brake device for a vehicle, comprising an exhaust shutter mounted in an exhaust passage of an engine, and an actuator for opening and closing the exhaust shutter,
An exhaust brake device for a vehicle, wherein a resonator chamber is provided in an exhaust passage on the exhaust gas upstream side of the exhaust shutter. In an exhaust brake device for a vehicle, comprising an exhaust shutter mounted in an exhaust passage of an engine, and an actuator for opening and closing the exhaust shutter,
An exhaust brake device for a vehicle, wherein the opening degree of the exhaust shutter is controlled in accordance with the engine speed when the exhaust brake is operated.

Images