JPH06317186A - Fuel limiting device of supercharger-equipped diesel engine - Google Patents

Abstract

PURPOSE:To provide a fuel limiting device of a supercharger-equipped diesel engine, which can easily adjust the limit operating position of an output portion at high accuracy. CONSTITUTION:A feed air pressure detector 30 for a supercharger 29, an engine speed detector 27 for an engine E, and a fuel limiting solenoid 22 are provided. The output portion 23 of the fuel limiting solenoid 22 can be switched between a limit operating position and a limit canceling position. At the limit operating position a governor lever 5a which engages directly with a control rack 6 can be received by means of the output portion 23. Only when a speed greater than a set value greater than the speed of the engine E at start and lower than the idling speed of the engine is detected by the engine detector 27 and the feed air pressure that the feed air pressure detector 30 detects is low, the output portion 23 is switched to the limit operating position so that the movement of the control rack 6 to the fuel increasing side is restrained via the governor lever 5a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel limiting device for reducing smoke that tends to occur at low speed and high load or during acceleration in a diesel engine with a supercharger.

[0002]

2. Description of the Related Art Generally, a diesel engine with a supercharger is
Since the supply air pressure is low at low speed and the increase of the supply air pressure is delayed at the time of acceleration, it is necessary to limit the maximum fuel injection amount and discharge an appropriate injection amount commensurate with the intake air amount in these cases. Conventionally, as a fuel limiter for a diesel engine with a supercharger of this type, as shown in FIG. 4, a booster configured to limit movement of a control rack (6) of a fuel injection pump (1) based on supply pressure. There is a compensator (50).

That is, this diesel engine with a supercharger
(E) is the fuel through the governor lever (5) that is swingably supported by the unbalanced force between the governor force (F) generated by the rotation of the engine (E) and the spring force (S) of the governor spring (10). It is configured to control the control rack (6) of the injection pump, and the boost compensator (50) is linked to this governor lever (5). This boost compensator (50) consists of a boost actuator (51) and a forward / backward transmission (52) derived from this boost actuator (51) .The boost actuator (51) is pressurized by a diaphragm (53) into a pressurizing chamber. (54)
And the spring working chamber (55).

The pressurizing chamber (54) extends from the supercharger (29) to the combustion chamber (3
4) The spring force of the biasing spring (56) placed in the spring working chamber (55) and the pressure chamber, which are in communication with the intake passage (28).
The diaphragm (53) is made variable by the unbalanced force of the supply pressure applied to (54). From the spring working chamber (55), the advancing / retreating rod (57) that constitutes the advancing / retreating transmitter (52) is led out so as to accompany the fluctuation of the diaphragm (53), and output to the tip side of this advancing / retreating rod (57). A part (58) is provided to receive the governor lever (5).

When the supply air pressure from the supercharger (29) becomes higher than the set pressure, the advancing and retracting rod is moved by the supply air pressure applied to the pressurizing chamber (54).
(57) advances and moves the output part (58) in the direction of releasing the restriction. On the other hand, when the supply pressure from the supercharger (29) drops below the set pressure, the advancing / retreating rod (57) retracts due to the spring force of the spring working chamber (55), and the output section (58) moves in the limiting direction. The governor lever (5) to receive the governor lever (5) and limit the swing of the governor lever (5) in the same direction as the spring force (S) of the governor spring (10).

In the boost compensator (50), when the engine is started, the output pressure (58) of the advancing / retreating rod (57) moves in the limit direction because the supply air pressure from the supercharger (29) is low, and the governor lever (5) ) Cannot swing toward the fuel increase side. Therefore, if the governor lever is directly engaged with the control rack, the amount of fuel cannot be increased at the time of starting, making it difficult to start the engine. Therefore, in the conventional diesel engine with supercharger (E), the governor lever is composed of the main governor lever (5a) and the sub-governor lever (5b), and the main governor lever (5a) is used for the control rack.
While engaging the rack pin (7) of (6), the output part (58) of the boost compensator (50) is linked to the auxiliary governor lever (5b), and the torque spring mechanism (11) is provided between both governor levers (5a, 5b). Is intervened.

[0007]

In the above-mentioned prior art, the adjustment of the control rack position in the fuel-restricted state is performed by the adjusting part (59) provided in the middle part of the forward / backward rod (57) to adjust the boost compensator (50). This is done by moving the position of the output unit (58). However, the torque spring mechanism (11) is interposed between the auxiliary governor lever (5b) received by the output section (58) and the main governor lever (5a) engaged with the control rack (6). Adjusting the control rack (6) to the proper fuel limit position by the adjusting part (59),
That is, it is extremely difficult to accurately adjust the limited operating position of the output part (58). Moreover, since the output part (58) of this prior art receives the intermediate part of the sub-governor lever (5b), the distance between this receiving part and the fulcrum of the governor lever (5b) is short, and the position of the control rack (6) is small. It is difficult to perform the above-mentioned adjustment accurately because the amount of movement of the output unit (58) corresponding to the adjustment amount is extremely small. SUMMARY OF THE INVENTION It is an object of the present invention to solve this problem and provide a fuel limiting device for a diesel engine with a supercharger, which can easily and highly accurately adjust the limiting operating position of the output portion.

[0008]

In order to achieve the above object, the present invention is characterized in that it is configured as follows. That is, the supply pressure detector (30) of the supercharger (29), the rotation speed detector (27) of the engine (E), and the fuel limiting solenoid (22) are provided, and the fuel limiting solenoid (22) The output part (23) is configured to be switchable between a limit operating position (31) and a limit releasing position (32), and when the output part (23) is switched to the limit operating position (31), it is directly engaged with the control rack (6). The governor lever (5a) is configured to be able to be received by the output part (23), and the rotational speed above the set rotational speed higher than the starting rotational speed of the engine (E) and lower than the idle rotational speed is equal to or higher than the rotational speed detecting device. (27), and only when the supply pressure detected by the supply pressure detector (30) is low, the output section (23) of the fuel limiting solenoid (22)
To the limited operating position (31),
The governor lever (5a) that directly engages with (6) limits the movement of the control rack (6) to the increasing side.

[0009]

[Operation] Since the output part (23) receives the governor lever (5a) directly engaged with the control rack (6), the output part (23)
A spring structure such as a torque spring mechanism (11) is not interposed between the control rack (6) and the control rack (6). Then, when the engine is started, the rotation speed detection tool (27) does not detect a rotation speed higher than a predetermined set rotation speed, and the output portion (23) of the fuel limiting solenoid (22) is set to the limit release position (32). After switching, the control rack (6) can be moved to the starting increase position. Rotation speed detection tool when the engine rotation speed rises above a predetermined set rotation speed
(27) detects this, in the state where the supply pressure from the supercharger (29) is low, the output part (23) of the fuel limiting solenoid (22) is switched to the limit operating position (31), Limit the movement of the control rack (6) to the fuel increase side via the governor lever (5a). When the engine speed further increases and the supply pressure from the supercharger (29) increases, the output part (23) of the fuel limiting solenoid (22) switches to the limit release position (32) and the control rack ( In 6), it is possible to move to the fuel increase side.

[0010]

According to the present invention, a torque spring mechanism is provided between the output section and the control rack while the engine can be easily started and the smoke at the time of low speed and high load or acceleration can be reduced. Since there is no interposition, the limited operating position of the output portion can be adjusted with extremely high accuracy. In addition, the output unit receives the governor lever that directly engages the control rack, so the tip of the governor lever can be received to increase the distance from the fulcrum of the governor lever, and the adjustment amount of the output unit corresponding to the movement amount of the control rack can be increased. Adjustment can be facilitated.

Further, when the governor lever can be received by the output part of the fuel limiting solenoid via the stop lever of the engine stopping device, the structure for receiving the governor lever can also be used as the engine stopping device. The whole structure can be simplified.

[0012]

1 to 3 show an embodiment of the present invention.
Is a front view of a governor device of a diesel engine with a supercharger, FIG. 2 is a schematic explanatory view of a fuel limiting device, and FIG. 3 is a front view of an engine stop device. The governor device (G) of the diesel engine (E) with a supercharger is arranged in the pump housing (2) of the fuel injection pump (1) attached to the engine (E), and The governor weight (4) fixed to the rotating shaft (3) and the control rack (6) of the fuel injection pump (1) are interlockingly connected via a governor lever (5).

That is, the governor lever (5) is composed of a main governor lever (5a) and a sub-governor lever (5b), and the tip of the main governor lever (5a) is attached to the rack pin of the control rack (6).
It engages with (7) and the middle part of the main governor lever (5a)
(8) receives the governor force (F) generated by the rotation of the governor weight (4), while the governor spring (10) is stretched between the sub governor lever (5b) and the speed control lever (9). Attach the torque spring mechanism (11) to the main governor lever (5a), and attach the tip of the torque pin (12) to the middle part (13) of the sub governor lever (5b).
The governor levers (5a, 5b) are interlocked with each other via the torque spring mechanism (11). As a result, the control rack (6) is controlled to move in and out by the unbalanced force between the governor force (F) generated by the rotation of the engine (E) and the spring force (S) of the governor spring (10).

A start spring (15) is stretched between the main governor lever (5a) and the fixed wall (14) of the engine (E), and the spring force of this start spring (15) causes the start of the engine. The control rack (6) can be moved to the starting increasing position via the main governor lever (5a).
Further, an engaging portion (16) is provided at the tip of the main governor lever (5a) so that it can be received by the stop lever (18) of the engine stop device (17).

As shown in FIG. 2, this engine stop device
The stop lever (18) of (17) is urged toward the normal operation side by the spring force of the return spring (19), and by operating the stop operation lever (20), the spring force of the return spring (19). It is configured to be able to move to the stop side against the. A fuel limiting solenoid (22) is arranged near the engine stop device (17),
The output portion (23) of the fuel limiting solenoid (22) is opposed to the tip portion (21) of the stop operating lever (20).

Power supply path to the fuel limiting solenoid (22)
The normally open type pressure switch (25) and the normally closed type pressure switch (26) are arranged in series in (24).
5) is configured to operate on the basis of the pressure detected by the lubricating oil pressure detection tool (27) that constitutes the engine speed detection tool. That is, the lubricating oil pressure detector (27) sets a lubricating oil pressure corresponding to a rotating speed higher than the starting rotating speed of the engine (E) and lower than the idle rotating speed, and the lubricating oil pressure is higher than the set oil pressure. When rising, normally open pressure switch
The contact of (25) is closed to energize.

On the other hand, the engine (E) is provided with a supply pressure detector (30) for detecting the supply pressure from the supercharger (29) arranged in the intake passage (28). When the pressure detector (30) detects a supply pressure higher than a predetermined pressure, the contact of the normally closed type pressure switch (26) is opened to interrupt the energization of the fuel limiting solenoid (22). Configured.

When the output portion (23) of the fuel limiting solenoid (22) receives power from the power feeding path (24), as shown in FIG.
The output part (23) is switched to the limited operating position (31), the stop lever (18) of the engine stop device (17) is turned to the stop side, and the tip of the stop lever (18) causes the tip of the main governor lever (5a) to move. Engagement part (1
6) is received to limit the swinging motion of the main governor lever (5a). On the other hand, when the power supply path (24) to the fuel limiting solenoid (22) is cut off, the output section (23) is switched to the limit release position (32), and the stop lever (18) causes the return spring (19). ), The main governor lever (5a) disengages the stop lever (18) from the engagement part (16) at the tip of the main governor lever (5a), and the governor force (F) and the spring force (S) of the governor spring (10) (S). It becomes possible to swing due to the unbalanced force with.

Therefore, when starting the engine from the stopped state, the lubricating oil pressure is low, so the normally open type pressure switch (25) is in a non-conducting state and the fuel limiting solenoid (22). The output section (23) is switched to the restriction releasing position (32), and the control rack (6) can be moved to the starting increasing position by the spring force of the start spring (15). After the engine starts, when the rotation speed rises above the idle rotation speed and the lubricating oil pressure reaches a predetermined pressure, the normally open type pressure switch (25) receives the lubricating oil pressure and becomes conductive, and the fuel limiting solenoid (22) is connected to the battery. Power from the (33) is supplied to the output (2
3) is switched to the restricted operating position (31). This limited operating position (3
The main governor lever (5a) is received by the output part (23) switched to 1) via the stop lever (18) of the engine stop device (17), and as a result, the control rack (6) is connected to the fuel increase side. Movement is restricted. Further, when the rotation of the engine (E) rises and the supply pressure from the supercharger (22) rises, the normally closed type pressure switch (18) operates and the fuel limiting solenoid (22)
The power supply to the control rack (6) is released by switching off the power supply to the output section (23) to the restriction release position (32).

In the above embodiment, the output lever (23) of the fuel limiting solenoid (22) receives the governor lever (5a) via the stop lever (18) of the engine stop device (17). The output unit (23) may directly receive the governor lever (5a). Further, the fuel limiting solenoid is not limited to the linear solenoid of the above embodiment, and a rotary solenoid may be used. Further, the engine speed detector can be configured by an appropriate device such as directly detecting the rotational speed of the rotating shaft, but it can be easily configured by using the lubricating oil pressure detector as in the above embodiment.

[Brief description of drawings]

FIG. 1 is a front view of a governor device for a diesel engine with a supercharger.

FIG. 2 is a schematic explanatory view of a fuel limiting device.

FIG. 3 is a front view of an engine stop device.

FIG. 4 is a view corresponding to FIG. 2, showing a conventional technique.

[Explanation of symbols]

1 ... Fuel injection pump, 5 ... Governor lever, 5a ... Governor lever (main governor lever) directly engaged with control rack, 6 ... Control rack, 10 ... Governor spring, 22 ... Fuel limiting solenoid, 23 ... Output section, 27 ... Rotation Number detection tool (lubrication oil pressure detection tool), 28 ... intake passage, 29 ... supercharger, 30 ... supply pressure detection tool, 31 ... limit operation position, 32 ... limit release position, E ... supercharged diesel engine, F: Governor force, S: Spring force of the governor spring.

Claims (2)

[Claims] 1. A control rack (6) for a fuel injection pump (1) mounted on a diesel engine (E), comprising:
The unbalanced force between the governor force (F) generated by the rotation of (E) and the spring force (S) of the governor spring (10) is controlled via the governor lever (5), and the intake passage (28) of the diesel engine (E) is controlled. Supercharger placed in
In a fuel limiting device for a diesel engine with a supercharger, which is configured to limit the operation of the governor lever (5) when the supply pressure from (29) is low, a supply pressure detector for the supercharger (29) ( 30), an engine (E) rotation speed detection tool (27), and a fuel limiting solenoid (22) are provided, and the output section (23) of the fuel limiting solenoid (22) is placed in a limited operating position.
(31) and the limit release position (32) are switchable, and when the limit operating position (31) is switched, the governor lever (5a) directly engaged with the control rack (6) is connected to the output section (5a). 2
It is configured so that it can be received in 3), and the rotational speed above the set rotational speed higher than the starting rotational speed of the engine (E) and lower than the idle rotational speed is equal to or higher than the rotational speed detection tool.
(27) and when the supply pressure detected by the supply pressure detector (30) is low, the output part (23) of the fuel limiting solenoid (22) is restricted to the operating position (31). Governor lever that directly engages the control rack (6)
A fuel limiting device for a diesel engine with a supercharger, characterized in that it is configured to limit the movement of the control rack (6) to the increasing side via (5a). 2. An output section (23) of a fuel limiting solenoid (22)
With the switch to the restricted operating position (31), use the stop lever (18) of the engine stop (17) to
The governor lever (5a) that directly engages with (6) is connected to this output part (23).
The fuel limiting device for a diesel engine with a supercharger according to claim 1, wherein the fuel limiting device is configured to be able to receive the fuel.