JPH09280074A - Controller of boost compensator of general-purpose engine with supercharger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent delay in response due to delay in operation of a boost compensator even if abrupt acceleration and load is applied to an engine from a no-load condition, prevent swinging of rotation speed of the engine at the time of transfer from a high load condition to the no-load condition of the engine, and suppress exhaust concentration of tree acceleration smoke to a low concentration. SOLUTION: A boost compensator lever of a boost compensator 14 is constituted in such a manner that a full rack position of a control rack of a fuel injection pump 12 can be regulated due to boost pressure of a general-purpose engine 11 with supercharger. A boost compensator release means 33 moves the boost compensator lever in the direction in which a fuel injection amount is increased forcedly irrespective of changes of boost pressure to release the regualtion of the control rack. A rotary sensor 48 detects rotation speed of the general-purpose engine 11, and a controller 49 controls the boost compensator release means 33 based on output detected by the rotary sensor 48.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for controlling a boost compensator of a general-purpose engine with a supercharger which drives a generator, a hydraulic excavator and the like.

[0002]

2. Description of the Related Art In a general-purpose engine with a supercharger of this type, for example, an engine for a generator, the engine is rotated at a rotational speed of about 700 rpm for a predetermined time, and then a controller is operated by a controller via a control lever of a fuel injection pump. Control, and 1500 in commercial frequency 50Hz area
The speed is rapidly increased to a predetermined rotation speed of rpm, and to a predetermined rotation speed of 1800 rpm in a commercial frequency of 60 Hz in an unloaded state. At this time, a large amount of fuel is supplied to the engine, but the exhaust gas pressure is still low, so the amount of increase in intake air by the supercharger is small. As a result,
Since the amount of intake air is smaller than the amount of injected fuel, there is a problem that the amount of black smoke in the exhaust gas increases. In recent years, the exhaust gas regulation law has been enacted for general-purpose engines, and in particular, the emission concentration of so-called free acceleration smoke, which is contained in the exhaust gas when the engine speed is rapidly increased from the idle speed with no load, is regulated. It became so.

In order to solve these problems, the fuel injection pump is provided with a boost compensator having a boo-con lever capable of regulating the full rack position of the control rack of the pump by boost pressure of the engine.
With this boost compensator, when the boost pressure does not rise even when the engine speed increases, for example, when the engine speed rapidly increases from the idle speed with no load, the full rack position of the control rack of the fuel injection pump is increased. Since it keeps moving in the direction of reducing fuel, it is possible to reduce the emission of black smoke.

[0004]

However, in the general-purpose engine with a supercharger having the conventional boost compensator described above, the boost pressure is low in the unloaded state, so that the full rack position of the control rack changes the fuel injection amount by the boost compensator. Even if a sudden load is applied to the engine in this state, the boost pressure does not rise sharply even if the engine is suddenly loaded in this state, and there is a problem that a response delay occurs. . Further, in the general-purpose engine with a supercharger having the conventional boost compensator,
When the engine shifts from a high load state to a no load state, the pressure of the supercharger slows down slowly, causing the boo-con lever that regulates the full rack position of the control rack to swing, resulting in an increase in engine speed. There was also a problem that wobbling occurred. An object of the present invention is to prevent a response delay due to an operation delay of a boost compensator even when a sudden acceleration and a load are applied to an engine from a no-load state,
A boost compensator control device for a general-purpose engine with a supercharger that can prevent fluctuations in the engine rotation speed when the engine shifts from a high-load state to a no-load state, and that can suppress the emission concentration of free acceleration smoke to a low level. To provide.

[0005]

The emission concentration of so-called free acceleration smoke contained in the exhaust gas when the engine speed is rapidly increased from the idle speed under no load condition is shown by the solid line and the broken line in FIG. As shown, it tends to decrease gradually as the engine speed increases. on the other hand,
At the same idle speed, when the boost control release means is activated (solid line), that is, when the regulation of the full rack position of the control rack is released, when the boost control release means is not activated (broken line), that is, the full rack position of the control rack The emission concentration of free acceleration smoke is higher than that when the fuel injection amount is regulated in the direction of decreasing the fuel injection amount. Moreover, in order to pass the exhaust gas regulation law, the emission concentration of free acceleration smoke is a predetermined value S
Although it must be below, if the predetermined engine speed becomes equal to or higher than the predetermined value N even when the boost control releasing means is operated, the exhaust concentration of the free acceleration smoke becomes equal to or lower than the predetermined value S. Therefore, when the engine rotation speed becomes equal to or higher than the predetermined value N, the regulation of the emission concentration of the free acceleration smoke is cleared, and the boost compensator is not necessary. Therefore, the present inventors have completed the present invention.

That is, the invention according to claim 1 is shown in FIGS.
As shown in, the boost compensator 14 having the boo compensator 27 capable of regulating the full rack position of the control rack 16 of the fuel injection pump 12 by the boost pressure of the general-purpose engine 11 with the supercharger, and the boo compever 27.
And the general-purpose engine 11 that can release the restriction of the control rack 16 by forcibly moving the fuel injection amount in the direction to increase the fuel injection amount regardless of the change of the boost pressure.
Sensor 48 for detecting the rotation speed of the
8 is a controller for a boost compensator for a general-purpose engine with a supercharger, which includes a controller 49 that controls the boost control releasing means 33 based on the detection output of 8. In this boost compensator control device, when the engine speed is rapidly increased from the idle speed with no load, the rotation sensor 48 detects that the engine speed has reached a predetermined value in the middle of this increase, and the controller 49 operates the boocon releasing means 33 to operate the boocon lever 27.
The restriction of the full rack position of the control rack 16 by the is released. At this time, the concentration of the free acceleration smoke discharged from the engine 11 is low and is below the regulation value.

When a sudden load is applied to the engine 11 from a no-load state with a rapid increase in the rotation speed, the control of the full rack position of the control rack 16 is released when the rotation speed reaches a predetermined rotation speed as described above. It As a result, it is possible to prevent the response delay due to the operation delay of the boost compensator 14. Further, when the engine 11 shifts from the high load state to the no load state, if the engine rotation speed is equal to or higher than the predetermined value, the boocon releasing means 33 is operating, and the boocon lever 27 causes the full rack position of the control rack 16 to be reached. Since the regulation of has been lifted,
Even if the boost pressure decreases slowly, the engine speed does not fluctuate and the engine speed is reduced smoothly.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an embodiment of the present invention will be described in detail with reference to the drawings. As shown in FIGS. 1 to 9,
The turbocharged generator engine 11 is a diesel engine, and a fuel injection pump 12 that injects fuel into a cylinder is mounted on the engine 11. A governor 13 is attached to one end surface of the pump 12, and a boost compensator 14 is attached to the other end surface (FIG. 1). A control rack 16 that controls the amount of fuel injected into the engine 11 is slidably inserted in the pump 13 in the longitudinal direction. One end of the control rack 16 is connected to a control lever 17 rotatably attached to the governor 13, and the other end of the control rack 16 is loosely inserted in the boost compensator 14 (FIGS. 2 to 7).

The boost compensator 14 is a case 18
A partition wall 23 for partitioning the inside of the case 18 into a first chamber 21 and a second chamber 22, an elastically deformable rubber diaphragm 24 built in the first chamber 21, and a partition wall 23 slidable Sliding shaft 2 that is inserted and has one end in contact with diaphragm 24
6 and a first support pin 3 whose center is inserted into the case 18
1, a boucon lever 27 that is rotatably supported by one and one end of which contacts the other end of the sliding shaft 26. Due to the diaphragm 24, the first chamber 21 is made into the intake introduction chamber 21a and the second chamber 22.
And a communication chamber 21b that communicates with. Further, two protrusions 27a and 27b are provided at the other end of the boocon lever 27, the control rack 16 abuts on one protrusion 27a, and the other protrusion 27b abuts on a first lever 41 of a boucon releasing means 33 described later. It is configured to be in contact with each other (Figs. 2 to 7).

Further, one end of a thin tube 37 is connected to the intake manifold 34 or the intake pipe 36 of the engine 11 (FIG. 1),
The other end of the thin tube 37 is connected to the intake introduction chamber 21a of the boost compensator 14 (FIGS. 1 and 2). Thereby, a part of the intake air of the engine 11 can be introduced into the intake air introduction chamber 21a through the thin tube 37, and the diaphragm 24 is elastically deformed by the pressure of the intake air, that is, the boost pressure. Further, the core metal 2 is placed at the center of the diaphragm 24.
4a is attached, and the sliding shaft 2 is attached to one end surface of the cored bar 24a.
One end of 6 is abutted (Fig. 2). The diaphragm 24 is biased by the first compression coil spring 51 so as to be elastically deformed in the direction of narrowing the intake introduction chamber 21a, and one end of the sliding shaft 26 is pressed against the core metal 24a of the diaphragm 24 by the second compression coil spring 52. Is urged to do.

A large-diameter disc 38 is fixed to the other end of the sliding shaft 26, and two claws 27c at one end of the boocon lever 27 are attached to the faces of the disc 38 facing the partition wall 23. Two
7c abuts (FIGS. 2 and 3). A length adjusting bolt 39 is attached to one of the protrusions 27a on the other end of the boocon lever 27, and the control rack 16 is configured to abut the tip of the bolt 39 (FIGS. 2, 3, 5 and 5). 7). The boocon lever 27 is rotated around the first support pin 31 by boost pressure to regulate the full rack position of the control rack 16. The boocon releasing means 33 includes a second support pin 32 rotatably attached to the case 18, and the support pin 3
2, a first lever 41 having one end fixed to one end, and a second lever 42 having the other end of the second support pin 32 substantially centered
And an electromagnetic solenoid 44 connected to one end of the second lever 42 via a connecting rod 43 (FIGS. 1 and 3 to 7).

The other end of the first lever 41 is the boocon lever 2
7, and the other end of the second lever 42 pivots between the first and second stoppers 61, 62 projecting from the outer surface of the case 18. Possible configurations (FIGS. 3, 4 and 6). A torsion coil spring 46 is wound around the second support pin 32.
6, one end 46 a of which is locked to the case 18 and the other end 46
Since b is locked to the second lever 42,
The other end of is urged to come into pressure contact with the first stopper 61 (FIG. 3). An angle adjusting bolt 47 is attached to the second stopper 62, and the second lever 42 is connected to the torsion coil spring 4
When the bolt 47 is rotated against the elastic force, the vicinity of the other end of the second lever 42 can come into contact with the tip of the bolt 47 (FIGS. 4 and 6). When the electromagnetic solenoid 44 (FIG. 1) of the boocon releasing means 33 is operated, the boocon lever 27 is forcibly moved in the direction of increasing the fuel injection amount regardless of the change of the boost pressure, and the full rack position of the control rack 16 is reached. It is supposed to lift the regulation.

A crankshaft (not shown) of the engine 11 is provided with a rotation sensor 48 for detecting the rotation speed of this shaft (FIG. 1). The detection output of the rotation sensor 48 is connected to the control input of the controller 49, and the control output of the controller 49 is connected to the electromagnetic solenoid 44. The controller 49 operates the electromagnetic solenoid 44 when the engine 11 reaches a rotation speed of a predetermined value N or more. The predetermined value N is 1200 to 1
It is preferably set in the range of 500 rpm. The generator has a commercial frequency of 1500 rpm in the 50 Hz area,
This is because the engine 11 rotates at 1800 rpm in the 60 Hz area.

In the above embodiment, a generator engine is used as a general-purpose engine, but a general-purpose engine may be a construction machine engine, a marine engine, or the like. In the construction machine engine, it is preferable to set the rotation speed of the engine that operates the booster releasing means in the range of 1000 to 2000 rpm. Further, in the above-described embodiment, the second support pin of the boocon releasing means is rotatably attached to the case, and the first lever that can come into contact with one protrusion of the other end of the boocon lever is fixed to one end of the second support pin. Then, the second lever to which the connecting rod is connected is fixed to the other end of the second support pin, but the first center for rotatably supporting the substantial center of the boocon lever.
The support pin is rotatably inserted into the case, the boocon lever is fixed to the first support pin, the first support pin is further projected from the case, and the connecting rod is connected to the projecting end.
The lever may be fixed. In this case, the second support pin and the first lever are unnecessary.

In the above embodiment, the rotation sensor directly detects the rotation speed of the crankshaft of the engine. However, the rotation sensor detects the rotation angle of the control lever of the fuel injection pump or the rotation speed of the alternator. You may do it. Further, in the above-mentioned embodiment, the second lever of the boocon releasing means is rotated by the electromagnetic solenoid via the connecting rod, but a fluid pressure cylinder or the like may be used, or the connecting rod or the second lever may be omitted. The second support pin may be directly rotated by using a rotary actuator such as a stepping motor with a gear.

In the engine 11 for a generator with a supercharger configured as described above, when the engine 11 is started, the engine rotation speed is, for example, 700 rpm, and after warming up for a predetermined time, the controller 49 causes the control lever of the governor 13 to operate. 17 is rotated in the direction in which the fuel injection amount is increased via a driving means (not shown), and the engine speed is set to, for example, 1
Raise up to 500 rpm with no load. During this ascent, the rotation sensor 48 indicates that the engine rotation speed is a predetermined value N,
For example, when detecting that the speed has reached 1200 rpm, the controller 49 operates the electromagnetic solenoid 44. When the electromagnetic solenoid 44 is actuated, the second
When the lever 42 rotates in the direction shown by the solid arrow in FIG.
However, at the same time, the first lever 41 rotates about the first support pin 31 in the direction shown by the solid line arrow in FIG. 2 and the other protrusion 27b at the other end of the boocon lever 27 moves to the position shown in FIG. Leading to. As a result, the regulation of the full rack position of the control rack 16 by the boocon lever 27 is released, and the emission concentration of free acceleration smoke at this time is shown in FIG.
The point P changes from point P to point Q, but it has decreased to the regulation value S or less according to the exhaust gas regulation law.

Further, even when a sudden load is applied to the engine 11 from a no-load state with a rapid increase in rotation speed,
Similar to the above, when the rotation speed N reaches 1200 rpm, the regulation of the full rack position of the control rack 16 is released, and the engine torque at this time is the point L in FIG.
To point M. As a result, even at a sudden load, the torque at the time of full boost can be output, the response delay due to the operation delay of the boost compensator 14 can be prevented, and the engine torque can be increased. Further, when the engine 11 shifts from the high load state to the no load state, the engine rotation speed is 1200r.
If it is pm or more, the boo-con releasing means 33 is operating, and the boo-con lever 27 controls the control rack 16
Since the regulation of the full rack position of is lifted, even if the boost pressure decreases slowly, the engine speed does not fluctuate and the engine speed is reduced smoothly.

[0018]

As described above, according to the present invention, the boocon lever restricts the full rack position of the control rack by the boost pressure, and the boocon releasing means forces the boocon lever to operate regardless of the change in the boost pressure. Since the control rack is released by moving the fuel injection amount in the direction of increasing the control rack, the controller controls the boost control releasing means based on the detection output of the rotation sensor that detects the rotation speed of the general-purpose engine. When the engine speed is rapidly increased from the idle speed with no load, the controller activates the boo-con releasing means when the engine speed reaches a predetermined value, and the boo-con lever causes the full rack position of the control rack. Remove the regulation. At this time, the concentration of free acceleration smoke emitted from the engine is low, which is below the regulation value.

When the engine speed is rapidly increased from the no-load state and the engine is rapidly loaded at the same time, the full rack position of the control rack is regulated when the engine speed reaches a predetermined level as described above. Canceled. As a result, it is possible to prevent a response delay due to a delay in the operation of the boost compensator. Further, when the engine shifts from the high load state to the no load state, if the engine rotation speed is equal to or higher than the predetermined value, the boocon releasing means is operating, that is, the regulation of the full rack position of the control rack by the boocon lever is released. Therefore, even if the boost pressure decreases slowly, the engine speed does not fluctuate and the engine smoothly decelerates.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a general-purpose engine with a supercharger including a boost compensator according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG. 3;

FIG. 3 is a sectional view taken along line BB of FIG. 2;

FIG. 4 is a view taken in the direction of arrow C in FIG. 3, showing a state where the boocon releasing means is inoperative.

FIG. 5 is a cross-sectional view taken along the line DD of FIG. 3, showing a state where the boocon releasing means is inoperative.

FIG. 6 is a view corresponding to FIG. 4, showing a state in which the boocon releasing means is activated.

FIG. 7 is a sectional view corresponding to FIG. 5, showing a state in which the boocon releasing means is activated.

FIG. 8 is a diagram showing changes in engine torque with respect to changes in engine rotation speed when the boost pressure of the boost compensator is full boost and zero boost.

FIG. 9 is a diagram showing changes in the exhaust concentration of free acceleration smoke when the engine speed is rapidly increased when the boost compensator releasing means is activated and deactivated.

[Explanation of symbols]

11 Engine for Generator with Supercharger (General-purpose Engine with Supercharger) 12 Fuel Injection Pump 14 Boost Compensator 16 Control Rack 27 Boocon Lever 33 Boocon Release Means 48 Rotation Sensor 49 Controller

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Seiji Fujino 3-1-1 Hinodai, Hino-shi, Tokyo Inside Hino Motor Co., Ltd.

Claims (1)

[Claims] 1. A boost compensator (14) having a boocon lever (27) capable of restricting a full rack position of a control rack (16) of a fuel injection pump (12) by boost pressure of a general-purpose engine (11) with a supercharger. A boocon releasing means (33) capable of releasing the regulation of the control rack (16) by forcibly moving the boocon lever (27) in a direction to increase the fuel injection amount regardless of the change of the boost pressure, A rotation sensor for detecting the rotation speed of the general-purpose engine (11)
A control device for a boost compensator for a general-purpose engine with a supercharger, comprising (48) and a controller (49) for controlling the boost control releasing means (33) based on a detection output of the rotation sensor (48).