JPS608125Y2 - Exhaust brake control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an exhaust brake control device, particularly to a device that cuts off the supply of fuel to an engine when the exhaust brake is activated.

In a fuel control device, such as a type that uses a pneumatic governor to control the fuel supplied to the engine,
The fuel is controlled by the pressure difference between the negative pressure generated in the intake pipe and the atmospheric pressure depending on the amount of air taken into the engine, and the larger this pressure difference is, the more the fuel supply is reduced.

By the way, when the exhaust brake is activated, the amount of air flowing in is also reduced because it prevents exhaust gas from flowing out from the engine, so when the exhaust brake is activated using the pneumatic governor, the pressure difference becomes smaller. , instead supplying (injecting) fuel to the engine.

Since the fuel injected into this engine burns to produce at least output, it burns with little external airflow which actually reduces the exhaust braking force, so it emits exhaust smoke, and furthermore, this exhaust Smoke (carbon) adheres to the exhaust brake valve, etc., and obstructs its operation.

In addition, in order to obtain the above pressure difference, some exhaust brake valves are provided with an exhaust outlet to obtain inflow air, but in such cases, the exhaust is not completely blocked and efficiency is reduced. This prevents a good exhaust braking action from occurring.

In view of the foregoing, it is an object of the present invention to provide a device that prevents wasteful injection of fuel when the exhaust brake is applied in a vehicle equipped with an engine equipped with a fuel control device, and performs an efficient exhaust brake action. It is.

The present invention will be explained below with reference to an embodiment shown in the drawings.

In the figure, solid lines connecting each part and dashed-dotted lines indicate piping.

1 is the battery that is the power source, 2 is the exhaust brake activation switch located in the driver's seat that opens and closes manually (OFF, ON), 3 is the accelerator switch that opens when you step on the accelerator pedal, and closes when you release it, and 4 is the clutch pedal. A clutch switch opens when stepped on and closes when released, and 5 is a three-way solenoid valve for the brake.

An electric circuit is constructed from the battery 1 to the solenoid valve 5 via each of the switches 2, 3, and 4.

6 is a vacuum pump that generates negative pressure; 7 is a vacuum tank that maintains the negative pressure generated by the vacuum pump 6; 8 is a vacuum chamber; 9 is an exhaust brake valve that opens and closes by the operation of the vacuum chamber 8; 10 is an exhaust brake valve 9 This is the exhaust pipe to which the exhaust pipe is attached.

Piping is provided from the vacuum pump 6 and the vacuum tank 7 to the vacuum chamber 8 via the three-way brake solenoid valve 5.

When the exhaust brake actuation switch 2, accelerator switch 3, and clutch switch 4 are each closed and the three-way brake solenoid valve 5 is energized, negative pressure 1 generated in the vacuum pump 6 and further maintained in the vacuum tank 7 is applied to the vacuum chamber 8. is sucked into operation and closes the exhaust brake valve 9.

Further, when the energization is removed, the chamber 8 is communicated with the atmosphere and the exhaust brake valve 9 is opened.

11 is a speed switch, for example, the vehicle speed or the set speed (15 mph)
This is a signal that emits a signal when the distance exceeds 1,000 kilometers (kilometers).

Numeral 12 is a neutral switch that opens when the transmission is in the neutral position and closes when the transmission is in the shift position. Numeral 13 is a controller that is connected to the speed switch 11 and the neutral switch 12, and receives signals from both switches.

Further, the controller 13 is branched from and connected to the extension of three switches, the exhaust brake operation switch 2, and the accelerator and clutch switches 3 and 4, and a signal is input even when all of these switches are ON. It looks like it will.

That is, when the transmission is in the shift position, the vehicle speed is 15 b/h or more, which is a certain speed that uses a large amount of fuel, and the vehicle is traveling downhill, for example, and at this time, the accelerator pedal and clutch pedal are not depressed. If the exhaust brake activation switch is turned on when the exhaust brake is not
The controller 13 is set to operate, and the operating conditions of the controller are set so that the three-way solenoid valve described later is opened to communicate the vacuum source and the negative pressure chamber of the governor.

14 is a three-way solenoid valve for a governor, and 15 is an intake pipe, which is provided with an intake negative pressure outlet 15b and an atmospheric pressure outlet 15c for taking out the negative pressure generated by the intake air of the throttle valve 15a1.

A pneumatic governor 16 controls the fuel supplied from the injection pump to the engine, and is divided by a diaphragm 16a to form a negative pressure chamber 16b and an atmospheric chamber 16c.

Further, a spring 16d is inserted into the negative pressure chamber 16b to urge a control rack 16e for increasing and decreasing fuel, which is interlocked with the diaphragm 16a, in the direction of increasing fuel.

The three-way solenoid valve 14 for the governor is connected to the negative pressure outlet 1 of the intake pipe 15.
5b and the negative pressure chamber 16d of the governor, and are further connected to a vacuum pump 6 and a vacuum tank 7, which are negative pressure sources, respectively, and connected to the controller 13.

That is, the governor negative pressure chamber is suctioned not only by the intake negative pressure but also by the negative pressure generated by the vacuum pump.

Further, the atmospheric pressure outlet 15c and the atmospheric chamber 16c are also piped.

When the exhaust brake activation switch 2, accelerator switch 3, and clutch switch 4 are closed and a signal is input to the controller 13, and signals are also input from the speed switch 11 and the neutral switch 12, the three-way solenoid valve for the governor is energized and the vacuum is activated. The pump 6 and the vacuum tank 7 are communicated with the negative pressure chamber 16b.

Then, due to the negative pressure of the vacuum pump 6, the negative pressure chamber 16b
is attracted, and the control rack 16e, which is interlocked with the diaphragm 16a, is moved in the direction of decreasing fuel against the spring 16d, resulting in a non-injection state.

Further, when any one of the above signals ceases to be emitted to the controller 13, the energization to the solenoid valve 14 is canceled, and the negative pressure outlet 15b and the negative pressure chamber 16b are brought into communication, returning to the normal operating state.

Note that 17 is a pilot lamp that lights up when the exhaust brake operation switch 2 is closed.

Now, when the exhaust brake action is required to decelerate the vehicle, manually turn the exhaust brake activation switch 2 to ON.
When the accelerator switch 3 and the clutch switch 4 are turned on by releasing the accelerator pedal and the clutch pedal, the three-way brake solenoid valve 5 is energized.

Then, the vacuum pump 6 (vacuum tank 7) and the vacuum chamber 8 are brought into communication, and the chamber 8 is sucked by the negative pressure generated by the pump 6, thereby closing the exhaust brake valve 9 and performing a braking action.

At this time, if the vehicle speed is higher than the set speed and the transmission is in the shift position, the speed switch 11 and the neutral switch 12
A signal is input to the controller 13 from.

The controller 13 has already activated the exhaust brake activation switch 2,
The three-way governor solenoid valve 14 is energized by the simultaneous input of the signal indicating the exhaust brake operating state and the two signals input at the time when the accelerator switch 3 and clutch switch 4 are closed.

Then, the vacuum pump 6 (vacuum tank 7) and the governor negative pressure chamber 16b communicate with each other, and the negative pressure generated by the vacuum pump 6 causes the diaphragm 1
6a is attracted against the spring 16d.

Since the diaphragm 16a is interlocked with the control rack 16e, the rack 16e is moved in the fuel decreasing direction to bring about a no-fuel injection state.

When the vehicle speed is decelerated by the action of the exhaust brake and becomes below a set value, no signal is sent from the speed switch 11 to the controller 13.

The controller 13 has three states (exhaust brake operation,
The governor three-way solenoid valve 14 is energized when the signals for the gear shift position and the set speed of the transmission are input at the same time, so if one of the above signals is not input, the solenoid valve 1
4 blocks the vacuum pump 6 (vacuum tank 7) and the negative pressure chamber 16b, and connects the negative pressure outlet 15b of the intake pipe to the negative pressure chamber 1.
6b.

As a result, fuel control is performed using normal intake negative pressure and atmospheric pressure, ensuring an idling state.

At this time, the vehicle is in a state before it comes to a stop, so either the exhaust brake activation switch 2 is turned OFF, or the clutch pedal is depressed and the clutch switch 4 is turned OFF, and the exhaust brake valve 9 is also released. There is no problem since normal operation is performed.

However, if the no-injection state continues, the engine will actually stop.

As described above, in a system equipped with a pneumatic governor 16 and combined to apply an exhaust brake, in the past, when the exhaust brake valve 9 was closed, a large amount of fuel was injected and the exhaust brake force was impaired. As in the invention, the governor negative pressure chamber 16b is sucked by the negative pressure generated by the vacuum pump 6, and the vehicle speed is increased to 15b/h, for example.
In the above, the non-injection state not only maximizes the exhaust braking force but also prevents the generation of exhaust smoke, which not only does not impede the operation of the exhaust brake valve but is also preferable in terms of pollution control.

In this embodiment, signals generated when the exhaust brake valve is closed, when the transmission is in the shift position, and when the speed is higher than the set speed are input to the controller 13 and sent to the governor three-way solenoid valve 14. The same effect can be obtained by connecting the exhaust brake operating switch 2, accelerator switch 3, clutch switch 4, neutral switch 12, and speed switch 11 in series to the solenoid valve 14, as shown in FIG. It is something that can be done.

Further, although the speed switch 11 is operated based on the vehicle speed, it may be operated based on the engine rotational speed.

Furthermore, although the exhaust brake valve 9 is operated by the negative pressure of the vacuum pump 6, the pneumatic governor 16
In addition to the suction force, an air pump may be used to operate with compressed air.

[Brief explanation of the drawing]

FIG. 1 is a system diagram showing one embodiment of the present invention, and FIG. 2 is a system diagram showing another embodiment. 1... Battery, 2... Exhaust brake activation switch, 3... Accelerator switch, 4
...Clutch switch, 5...3-way solenoid valve for brake, 6...Vacuum pump, 7
... Vacuum tank, 8 ... Vacuum chamber, 9 ... Exhaust flake valve, 11
... Speed switch, 12 ... Neutral switch, 13 ... Controller, 14.
... Three-way solenoid valve for governor, 15 ... Intake pipe, 16 ... Pneumatic governor.

Claims (1)

[Scope of utility model registration request] It constitutes an electric circuit from the power supply to the three-way solenoid valve for the exhaust brake via the exhaust brake activation switch, the accelerator switch and the clutch switch, which are turned ON when the accelerator pedal and clutch pedal are not depressed, and is an extension of the above three switches. A three-way solenoid valve that is operated by a neutral switch that is turned on at a gear shift position of the transmission and a speed switch that is turned on at a speed higher than a set speed is connected to the valve, and intake negative pressure and other negative pressure sources are selected through the three-way solenoid valve. is connected to the negative pressure chamber of the fuel control device, so that when all the above switches are turned on, the negative pressure of the other negative pressure source is guided to the fuel control device to put the fuel in a non-injected state. Exhaust brake control device.