JPH05231181A - Vibrationproof mechanism for diaphragm type actuator of turbosupercharged engine - Google Patents

Abstract

PURPOSE:To secure the stable operation by suppressing the pulsation of the intake pressure by arranging a resonator on the input side of an actuator when the intake secondary side pressure of a turbosupercharged engine to a fuel injection pump through the diaphragm type actuator. CONSTITUTION:A turbocharger 2 is installed on an engine 1. The suction pressure on the suction pipe secondary side 3 is introduced into one chamber 7 of a boost compensator 5 through a pipe 4. Accordingly, when the pressure in one chamber 7 overwhelms a spring 11 in the other chamber 8, a diaphragm 9 shifts, and a fuel injection pump 19 is operated in the fuel increase direction through a rod 10 and a rack 20. With this constitution, a resonator 24 for reducing the pulsation of the intake pressure is arranged on the input side of the boost compensator 5. For example, an air chamber 22 having a prescribed capacity V is dividedly formed by arranging a partitioning plate 21 inside one chamber 7, and a communication pipe 23 which communicates to one chamber 7 is installed on the partitioning plate 21.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a diaphragm actuator which operates by utilizing intake pressure of a turbocharged engine to prevent vibration due to intake pulsation.

[0002]

2. Description of the Related Art A boost compensator attached to a turbocharged engine takes out the intake pressure on the secondary side of the compressor of the turbocharger with a pipe or the like to remove the rod of a diaphragm type actuator. Through this, the rack of the fuel injection pump is operated to control the fuel injection amount.

That is, in the above structure, when the intake pressure on the secondary side is low and the spring force built in the actuator cannot be overcome, the actuator does not operate and the movement of the rack is restricted. The fuel injection amount is kept low, but when the intake pressure rises and overcomes the spring, the rack is moved in the direction of increasing the injection amount, and fuel is injected according to the increase in the intake amount to increase the output. is there.

[0004]

By the way, the pressure taken out from the intake pressure has the pressure pulsation of the explosive primary component and is influenced by the inertia supercharging. Therefore, the spring incorporated in the actuator is used. In the state of being balanced by the pressure, the operation of the rod vibrates due to pulsation, and there is a problem that appropriate operation characteristics may not be obtained.

[0005]

SUMMARY OF THE INVENTION Here, the present invention provides a turbocharger engine turbocharger as described above.
The pulsation of the intake pressure is reduced by controlling the fuel injection amount by operating the rack of the fuel injection pump through the diaphragm type actuator of the boost compensator to control the intake secondary pressure of the compressor of the jar. A vibration damping mechanism for a diaphragm type actuator of a turbocharged engine, characterized in that a resonator is provided on the input side of the actuator.

[0006]

According to the present invention, when the intake pressure of the turbocharger is actuated by the diaphragm actuator to operate the rack of the fuel injection pump, the resonator provided on the input side of the actuator is operated. The action absorbs the pulsation of the intake pressure, thereby suppressing the vibration of the rod of the actuator and stabilizing the operation of the rack connected to this rod through an interlocking system. is there.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in detail with reference to the accompanying drawings. First, FIG. 3 shows a conventional structure.
In the figure, 1 is an engine, 2 is a turbocharger, 3 is an intake pipe secondary side, 4 is a guide from this intake pipe secondary side 3,
It is a pipe connected to a stomp compensator (hereinafter referred to as a booster) 5.

The booster 5 includes a diaphragm type actuator, which comprises a main body 6, a diaphragm 9 for partitioning the inside of the main body 6 into two chambers 7 and 8, and this diaphragm 9.
A rod 10 which is connected to the main body 6 and protrudes out of the main body 6, and in the chamber 8 on the side where the rod 10 is connected, the diaphragm 9
And a spring 11 that is compressed between the main body 6 and the main body 6.

The projecting end 12 of the rod 10 abuts on the cam surface 15 of the torque cam 14 which moves forward and backward with respect to the stopper 13, and the cam surface 15 is engaged with the end portion of the lever 17 supported by the fulcrum 16. In contrast, the rack 20 of the fuel injection pump 19 is pivotally supported at the intermediate portion of the lever 17 via the fulcrum 18.

In the above structure, the intake pressure on the secondary side 3 of the intake pipe is transmitted to the chamber 7 of the booster 5 via the pipe 4, and when this pressure overcomes the spring 11, the diaphragm 9 fluctuates, This movement is transmitted to the rack 20 via the rod 10, the torque cam 14, and the lever 17,
The fuel injection pump 19 moves the rack 20 in the injection amount increasing direction to inject the fuel corresponding to the increase in the intake amount.

With the above structure, the diaphragm 9 of the bucon 5 is affected by the pulsation of the intake pressure on the intake secondary side 3 and, in some cases, the fluctuation of the intake air amount due to inertial supercharging.
Operates improperly, which causes the rod 10 to vibrate, which is transmitted to the rack 20 and causes the fuel injection amount to fluctuate, which in turn makes the rotation of the engine unstable and causes vibration of the engine. Problems such as an increase in exhaust smoke will occur.

FIG. 4 is a graph showing the above situation. As is apparent from FIG. 4, when the intake pressure exceeds a certain level, the rod starts to operate, and when the pressure rises, the rod moves until it hits the stopper. It vibrates in the range shown.

The present invention proposed as a means for preventing the occurrence of such a situation will be described below with reference to FIGS. 1 to 3. It should be noted that the same or equivalent parts as those of the conventional example shown in FIG.

In the present invention, the pulsation of the intake pressure of the intake pipe secondary side 3 is provided in the main body 6 of the booster 5 itself or in the middle of the pipe 4 connecting the main body 6 and the intake pipe secondary side 3. The above-mentioned problem is solved by incorporating a resonator for pressing down.

In FIG. 1, a partition plate 2 is provided in a chamber 7 inside the main body 6.
1 is provided to form an air chamber 22 having a volume V, and a communication pipe 23 communicating with the chamber 7 is attached to the partition plate 21. When the length of the communication pipe 23 is l and the cross-sectional area is s, it is necessary to satisfy the following equation in order to reduce the pressure pulsation. That is, if the pulsation frequency is fn and the speed of sound is c,

[Equation 1] Becomes In the present invention, the resonator 24 that satisfies the above formula
Is provided, the fluctuation of the intake pressure is absorbed, the displacement of the rack 20 caused by the vibration of the rod 10 is suppressed, and the operation of the fuel injection pump 19 is appropriately maintained.

FIG. 2 shows an example in which the resonator 24 is provided in the middle of the pipe 4 instead of being provided inside the booster 5, and in this case, the volume V of the air chamber 22 and the communication pipe. Two
The numerical values including the length 1 of 3 are the same as those in the example shown in FIG.

[0017]

According to the above-mentioned structure of the present invention, in the one provided with the booster including the diaphragm type actuator operated by utilizing the intake pressure of the turbocharged engine, the intake secondary side By effectively absorbing the pressure pulsation and maintaining the injection amount of the fuel injection pump appropriately,
There are many things that contribute to stable engine rotation.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an embodiment including a mechanism of the present invention.

FIG. 2 is a configuration diagram of another embodiment of the present invention.

FIG. 3 is a configuration diagram of a conventional example.

FIG. 4 is a graph showing a situation of occurrence of vibration related to intake pressure and rod operating amount.

[Explanation of symbols]

 1 engine 5 booster (boost compensator) 24 resonator

Claims (1)

[Claims] 1. A fuel injection pump rack is actuated by operating an intake secondary pressure of a compressor of a turbocharger engine of a turbocharger engine through a diaphragm type actuator of a boost compensator to operate the fuel. In the one for controlling the injection amount, a resonator for reducing the pulsation of the intake pressure is provided on the input side of the actuator, and the vibration isolation of the diaphragm type actuator of the turbocharged engine is characterized. mechanism.