JPH0722049U - Third brake control device for vehicle - Google Patents

Abstract

(57) [Summary] [Object] The present invention aims to provide a third brake control device for a vehicle that does not release an afterfire or unburned fuel amount to the atmosphere even when the accelerator pedal is depressed when the third brake is released. I am trying. [Structure] Third method using throttle loss of intake air in the cylinder
In a control device for a vehicle having a brake, a valve for discharging a small amount of air in a cylinder is provided at least in a compression stroke, and a control device 15 for operating the valve as a third brake is provided. The control device 15 releases the third brake. When the accelerator opening has moved to a certain value or more, the fuel injection start timing is determined based on the relationship between the engine speed and the fuel injection start delay time that is provided in advance.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a vehicle control device having a third brake that utilizes a loss of throttled intake air in a cylinder.

[0002]

[Prior art]

 Brake devices that decelerate or stop the vehicle include, for example, the first brake that is commonly used as the main brake that brakes the rotating body provided on the wheel, and the exhaust pipe that is equipped with a shutter to prevent the exhaust stroke of the engine. It is classified into the second brake, which is used as an aid such as decelerating by utilizing loss, and the third brake, which is another braking device.

As an example of the third brake utilizing the throttle loss of the intake air in the cylinder, as shown in FIG. 4, the rocker arm 26 for operating the exhaust valve 21 of the engine is attached to the rocker shaft 23 by an eccentric bush. The eccentric bush 24 is attached via an arm 25 for rotating the eccentric bush 24, and the eccentric bush 24 is rotated by the actuator 22 to move the rocking center of the rocker arm.

A technique is known in which the valve lift by the cam 27 is changed so that the exhaust valve 21 is slightly opened in the compression stroke, and the exhaust valve 21 is operated as the third brake. A similar technique is disclosed in Japanese Utility Model Publication No. 3-27844.

[0005]

[Problems to be solved by the device]

 However, in the above technology, it takes 0.1 to 0.2 seconds until the valve is closed by releasing the actuator operation when releasing the brake, and if the driver depresses the accelerator pedal during this time, fuel is injected. Therefore, there is a problem that the fuel that has not burned in the cylinder causes an afterfire that burns in the exhaust pipe or the muffler, and releases unburned fuel to the atmosphere.

[0006] Although there is Japanese Utility Model Laid-Open No. 56-159603 by the applicant of the present application, it is a technology relating to improvement of the effectiveness of the third brake, and Japanese Utility Model Laid-Open No. 3-27844 discloses the braking force when the exhaust brake is operated. It is related to improvement, and none of them solves the above problems.

Therefore, an object of the present invention is to provide a third brake control device for a vehicle that does not release an afterfire or an unburned fuel amount to the atmosphere even when the accelerator pedal is depressed when the third brake is released.

[0008]

[Means for Solving the Problems]

 According to the present invention, in a control device for a vehicle having a third brake that utilizes intake air throttle loss in a cylinder, a valve for discharging a small amount of air in the cylinder is provided at least in a compression stroke, and the valve is a third valve. A control device that operates as a brake is provided, and when the accelerator opening moves to a certain value or more when the third brake is released, the control device sets the fuel consumption based on the relationship between the engine speed and the fuel injection start delay time that is set in advance. It is configured to determine the timing of injection start.

[0009]

[Action]

 In the vehicle third brake control device configured as described above, when the driver releases the third brake and depresses the accelerator pedal, the control device detects a change in the opening of the accelerator pedal and the change in opening is constant. When the value is equal to or higher than the value, the fuel injection start is sent to the normal control, so that the unburned fuel does not flow to the exhaust pipe and the after-fire does not occur.

[0010]

[Preferred Embodiment]

 The exhaust valve may be opened slightly instead of the valve that discharges a small amount of air in the cylinder.

[0011]

【Example】

 Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows an essential part of the present invention. In FIG. 1, a rocker arm 6 is attached to a rocker shaft 1 via an eccentric bush 2, and an arm 3 is fixed to the eccentric bush 2. There is.

The groove 3a provided at the tip of the arm 3 is configured to engage with the rod 9a of the actuator 9 which is hydraulically operated.

Further, one end of the rocker arm 6 is engaged with the cam 5 via the roller 4, and the other end is in contact with the end portion of the stem of the exhaust valve 8 via the adjust bolt.

Further, the actuator 9 is connected to an unillustrated hydraulic circuit of an engine via an electromagnetic opening / closing valve 11 in an oil circuit 11a.

The fuel injection nozzle 13 is connected to a fuel injection pump 12 by an injection pipe 14, and the injection pump 12, the engine rotation sensor 16, the accelerator opening sensor 17, and the electromagnetic opening / closing valve 11 are respectively connected by an electric circuit. It is connected to the control device 15.

Reference numeral 10 indicates a cylinder head.

The operation will be described below with reference to FIG.

At the time of operation, it is determined whether the third brake switch is ON or not (step S 1). If NO, the process returns, and if YES, it is determined whether the accelerator opening has moved from 0 to 10% or more (step S2). If NO, the process returns, and if YES, the delay time is calculated from the data of the engine speed of the control device 15 and the delay time (step S3 and FIG. 3), and t time (for example, 0.5 seconds). Fuel injection is started with a delay (step S4). Therefore, the fuel is not injected before the exhaust valve 8 enters the normal operating state, and the unburned fuel does not flow to the exhaust pipe.

[0020]

[Effect of device]

 Since the present invention is configured as described above, when the third brake is released, fuel is not injected even in that process, so unburned fuel may come out of the exhaust pipe or an afterfire may occur. There is no such thing.

Therefore, the exhaust pipe and the muffler are not damaged, and no unpleasant odor due to unburned fuel is emitted.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a main part of a third brake device showing an embodiment of the present invention.

FIG. 2 is a flowchart of the control of FIG.

FIG. 3 is a diagram illustrating a relationship between an engine speed and a fuel injection start delay time.

FIG. 4 is a side view showing an example of a conventional third brake.

[Explanation of symbols]

 1, 23 ... Rocker shaft 2, 24 ... Eccentric bush 3, 25 ... Arm 5, 27 ... Cam 6, 26 ... Rocker arm 8, 21 ... Exhaust valve 9, 22 ... Actuator 10 ... Cylinder head 12 ... Fuel injection pump 13 ... Fuel injection nozzle 15 ... Control device 16 ... Engine rotation sensor 17 ... Accelerator opening sensor

Claims (1)

[Scope of utility model registration request] 1. A control device for a vehicle having a third brake utilizing intake air throttle loss in a cylinder, wherein a valve for discharging a small amount of air in the cylinder is provided at least in a compression stroke, and the valve is operated as a third brake. When the accelerator opening moves to a certain value or more when the third brake is released, the control device controls the fuel injection start based on the relationship between the engine speed and the fuel injection start delay time that is provided in advance. A third brake control device for a vehicle, which is configured to determine a time.