JP2725111B2 - Electric control type fuel limiting device for sudden acceleration of diesel engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric control type fuel limiting device for sudden acceleration of a diesel engine.

[0002]

2. Description of the Related Art When a diesel engine is rapidly accelerated, black smoke may be generated temporarily due to a response delay of a supercharger or an overrun of a control rack of a fuel injection pump. ○ (In the case of turbocharger response delay) Immediately after the diesel engine is rapidly accelerated from a low speed to a high speed, the rise speed of the supply pressure of the turbocharger is delayed with respect to the rise speed of the engine due to the compressibility of air. . As a result, the amount of air is insufficient for the fuel injection amount, and black smoke is generated. ○ (In case of overrun of control rack) See FIG. 5 When the governor lever 1 is rapidly accelerated from the low speed position L to the high speed position H, the tension of the governor spring 11 suddenly increases,
The control rack 7 of the injection pump 3 is moved to the fuel increasing side E via the spring side lever 10a and the governor lever 10.
Move rapidly to Then, the spring side lever 10
After a reaches the full load position 4/4 and is received by the fuel limiter 13, the control rack 7 overruns from the torque-up position Tu to the start increasing position S due to kinetic inertia. As a result, the fuel injection amount becomes excessive with respect to the air amount, and black smoke is generated.

[0003]

2. Description of the Related Art In order to prevent the generation of black smoke at the time of rapid acceleration of a diesel engine, in the prior art, an electric control type fuel limiting device for a rapid acceleration of a diesel engine shown in FIG. Was proposed to. (Japanese Patent Application Hei 2-41
No. 0811) This device is configured as follows. That is, a fuel limit command switch 2 is attached to the speed control lever 1 of the diesel engine, a fuel limit actuator 4 is attached to the fuel injection pump 3, and the fuel limit command switch 2 is set via the fuel limit holding timer 5 via the fuel limit holding timer 5. A fuel limit control circuit 6 is constituted by being linked to the fuel limit actuator 4 so that a command can be operated. When the speed control lever 1 is operated from the low speed position L to the high speed position H, the fuel limit command switch 2 is detected and operated at the fuel limit command position M during the operation. The fuel limiting actuator 4 continues to advance to the fuel limiting position J for the fuel limiting holding time T1 set by the fuel limiting holding timer 5, and the control rack 7 of the fuel injection pump 3 moves to the fuel limiting position J. It is configured to be received and placed.

[0004]

In the above prior art,
There are the following problems: When the speed control lever 1 is set at a medium speed position near the fuel limit command position M, the speed control lever 1 may frequently turn on / off the fuel limit command switch 2 due to engine vibration. Then, the fuel limiting actuator 4 frequently performs wasteful operation, and its life is shortened. It is an object of the present invention to prevent a fuel limiting actuator from being uselessly operated and shortening its life when a governing lever set at a middle speed position malfunctions a fuel limiting command switch. And

[0005]

According to the present invention, in order to achieve the above-mentioned object, the following improved structure is added to the above-mentioned premise structure, for example, as shown in FIGS. That is, the control rack 7 is
When a predetermined high load position P set in the above is reached, this is detected by the high load position detection switch 8 and the fuel restriction allowable timer 9 is operated. This fuel limit
The timer 9 is provided for detecting the high load of the high load position detection switch 8.
Start of signal input based on input of detection signal
From the point in time until the fuel limit allowable time T2 elapses
Output a fuel limit permission signal to the fuel limit holding timer 5 described above.
Configure to force. This fuel limit allowable timer 9
Before reaching the end point t3 of the fuel limit allowable time T2,
Based on the detection operation of the fuel limit command switch 2,
The fuel limit actuator according to the fuel limit holding timer 5
4 is allowed to advance to the fuel limit position J and the fuel
The limit holding timer 5 moves the fuel limit actuator 4 to the fuel limit position.
The fuel is held at the position J for the fuel limit holding time T1. This
On the other hand, this fuel limit allowable timer 9
After the end time t3 of the allowable time T2 has elapsed,
The fuel based on the detection operation of the fuel limit command switch 2
Fuel of the fuel limit actuator 4 by the charge limit holding timer 5
The system is configured to prohibit the advance operation to the restricted position J.
It is characterized by.

[0006]

The present invention operates as follows. ○ (Regular fuel limiting operation) See FIGS. 3A to 3H As shown in FIG. 3A, the speed adjusting lever 1 is rapidly accelerated from the low-speed position L to the high-speed position H. When the speed control lever 1 has passed the fuel limit command position M, as shown in FIG.
The fuel limit command switch 2 is turned on, and the fuel limit holding timer 5 is turned on as shown in FIG. By the rapid acceleration operation, the tension of the governor spring 11 suddenly becomes stronger than the centrifugal force of the governor weight 12, and the control rack 7 is rapidly drawn from the partial load position to the fuel increasing side E as shown in FIG. . When the control rack 7 reaches the high load position P, the high load position detection switch 8 is turned on as shown in FIG. 3E, and the fuel restriction allowable timer 9 is turned on as shown in FIG. When the two timers 5 and 9 are turned on, the fuel limit actuator 4 advances from the fuel limit release position K to the fuel limit position J as shown in FIG.
As shown in FIG. 3D, the control rack 7 is immediately pushed back to the fuel limit position J to prevent the control rack 7 from excessively moving to the fuel increasing side E any more. Thereafter, when the fuel limit holding timer 5 is turned on as shown in FIG. 3C and then turned off after the fuel limit holding time T1 has elapsed, as shown in FIG. The speed has increased considerably, and the supercharging pressure of the supercharger 23 has also increased considerably. When the fuel limit holding timer 5 is turned off, the fuel limit actuator 4 is retracted from the fuel limit position J to the fuel limit release position K as shown in FIG. Then
As shown in FIG. 3D, the control rack 7 is pushed by the governor from the fuel limit position J to the torque-up position Tu beyond the full load position 4/4, and the engine rotates as shown in FIG. 3H. Increase speed rapidly. At this time, since the supercharging pressure of the supercharger 23 has already been sufficiently increased, no black smoke is generated.

○ (Prevention of wasteful operation of fuel restriction, part 1)
4 (A) to 4 (H) A case where the speed control lever 1 is set at a position slightly lower than the fuel limit command position M as shown in FIG. 4 (A) will be described. As shown in FIG. 4 (B), the fuel limit command switch 2 is basically turned off, but may be erroneously turned on instantaneously due to the vibration of the governing lever 1 due to the vibration of the engine. Due to this turning on, the fuel limit holding timer 5 turns on as shown in FIG. However, FIG.
As shown in FIG. 4D, the control rack 7 is maintained at the partial load position by the action of the governor and does not go to the high load position P, so that the high load position detection switch 8 is turned off as shown in FIG. As shown in FIG. 4 (F), the fuel limit allowable timer 9 remains off. As a result, FIG.
As shown in (G), the fuel limit actuator 4 is in the fuel limit release position K.
, And there is no needless operation to the fuel limit position J. （(Prevention of wasteful operation of fuel restriction, part 2) Illustration is omitted The case where the governing lever 1 is set at a position slightly higher than the fuel restriction command position M will be described. Although the fuel limit command switch 2 is basically on, it may be erroneously turned off momentarily by the vibration of the governing lever 1 due to the vibration of the engine. This turning off resets the fuel limit holding timer 5. The return to the on state immediately after the off state turns on the fuel limit holding timer 5 again.
However, as in the case of the first case, since the fuel limit allowable timer 9 is kept off, the fuel limit actuator 4 does not operate wastefully.

[0008]

The present invention is constructed and operated as described above, and has the following effects. In the medium speed operation state in which the speed control lever 1 is set near the fuel limit command position M , the engine load is a medium load or a light load.
You. Therefore, the control rack 7 functions as a governor.
And maintained at medium to light load position and high load
Position, the high load position detection switch 8 is turned off.
The fuel limit permissible timer 9 is turned off and the fuel
Turn off the limiter 4 and hold it at the fuel limit release position K
I have. In this middle-speed operation state, even when the fuel limit command switch 2 is erroneously turned on due to the vibration of the governing lever 1 due to the vibration of the engine and the fuel limit holding timer 5 is operated , the fuel limit actuator 4 allows the fuel limit to operate. Timer 9 off
To the fuel limit release position K, and the fuel limit position J
The wasteful operation is eliminated, and the reduction of the life due to the repetition of the wasteful operation can be eliminated.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a system diagram of an electric control type fuel limiting device at the time of rapid acceleration of a diesel engine, FIG. 2 is a connection diagram of a fuel limiting control circuit, and FIG.
FIG. 4 is a timing chart at the time of regular fuel limiting operation, and FIG. 4 is a timing chart at the time of preventing waste operation. In the figure, an intake / exhaust passage 21 of a supercharged diesel engine 20 is shown.
An exhaust turbine type supercharger 23 is attached to 22 and the fuel injection pump 3 is attached to a side wall 24 of the cylinder block. The governor lever 10 is pivotably supported on the engine 20 around a fulcrum 25 so as to be swingable.
Are linked to the fuel injection camshaft 26. A centrifugal governor weight 12 is attached to the fuel injection cam shaft 26 via a gear 27, and is linked with the governor lever 10. Control rack 7 for the fuel injection pump 3
Can be controlled via the governor lever 10 by balancing the elastic force of the governor spring 11 on the fuel increasing side E with the governor weight 12 and the governor force G of the governor weight 12 on the fuel decreasing side F. Then, the control rack 7 is moved through the governor lever 10,
The fuel restricting device 13 is configured to be able to receive the fuel at the fuel restricting position J. A fuel limiting command switch 2 is attached to the speed control lever 1 of the turbocharged diesel engine 20, and a fuel limiting actuator 4 is attached to the fuel injection pump 3. The charge limit command switch 2 is fixed to the pump housing 3 a of the fuel injection pump 3, and its contact 2 a faces the base of the speed control lever 1. The fuel limit command switch 2 is linked to the fuel limit actuator 4 via a fuel limit holding timer 5 via a fuel limit holding timer 5 so that a command can be operated.
Is configured. Reference numeral 14 denotes a power supply battery. And
When the speed control lever 1 is operated from the low speed position L to the high speed position H, the fuel limit command switch 2 is detected and operated at the fuel limit command position M in the middle of this operation. The fuel limit actuator 4 continues to advance to the fuel limit position J for the fuel limit hold time T1 set by the fuel limit hold timer 5, and the control rack 7 of the fuel injection pump 3 is received at the fuel limit position J. It is configured to be placed. Further, when the control rack 7 reaches a predetermined high load position P set in the high load area N, this is detected by a high load position detection switch 8 provided in the fuel limit control circuit 6. , The fuel limit permissible timer 9 is operated. The high load position detection switch 8 is, for example,
3 is electrically insulated from the pump housing 3a of the fuel injection pump 3 by an insulating member 13a.
When the fuel limiter 13 contacts the fuel limiter 13 and grounds it at a predetermined high load position P,
Is configured to operate. The fuel limit allowing timer 9 is connected to the fuel limit holding timer 5 in series. The high-load position detection switch 8 activates the fuel-limit permission timer 9 when detecting that the control rack 7 has reached the high-load position P, and operates based on the detection operation of the fuel-limit command switch 2. When the fuel limit actuator 4 is allowed to advance to the fuel limit position J, but the arrival at the high load position P is not detected, the fuel limit actuator 4 is not operated without operating the fuel limit permit timer 9. Is prevented from advancing to the fuel limit position J. In other words, this fuel restriction
The timer 9 is provided for detecting the high load of the high load position detection switch 8.
Start of signal input based on input of detection signal
From the point in time until the fuel limit allowable time T2 elapses
Output a fuel limit permission signal to the fuel limit holding timer 5 described above.
Configure to force. This fuel limit allowable timer 9
Before reaching the end point t3 of the fuel limit allowable time T2,
Based on the detection operation of the fuel limit command switch 2,
The fuel limit actuator according to the fuel limit holding timer 5
4 is allowed to advance to the fuel limit position J and the fuel
The limit holding timer 5 moves the fuel limit actuator 4 to the fuel limit position.
The fuel is held at the position J for the fuel limit holding time T1. This
On the other hand, this fuel limit allowable timer 9
After the end time t3 of the allowable time T2 has elapsed,
The fuel based on the detection operation of the fuel limit command switch 2
Fuel of the fuel limit actuator 4 by the charge limit holding timer 5
It is configured to prohibit the advance operation to the restricted position J
It is.

[Brief description of the drawings]

FIG. 1 is a system diagram showing an electric control type fuel limiting device for rapid acceleration of a diesel engine according to an embodiment of the present invention.

FIG. 2 is a connection diagram of a fuel limit control circuit according to the embodiment of the present invention.

FIG. 3 is a timing chart showing a normal fuel limiting operation according to the embodiment of the present invention.

FIG. 4 is a timing chart showing the embodiment of the present invention and preventing unnecessary operation.

FIG. 5 shows a conventional example, and is an operation system diagram of an electric control type rapid acceleration fuel limiting device for a diesel engine.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Governing lever, 2 ... Fuel limit command switch, 3 ... Fuel injection pump, 4 ... Fuel limit actuator, 5 ... Fuel limit holding timer, 6 ... Fuel limit control circuit, 7 ... Control rack, 8 ... High load position Detection switch, 9: fuel limit allowable timer, H: high speed position, J: fuel limit position, L: low speed position,
M: fuel limit command position, N: high load region, P: high load position , T1: fuel limit holding time, T2: fuel limit allowed
Interval, t3 ... end point.

Claims (1)

(57) [Claims] A fuel injection pump having a fuel limiting command switch (2) attached to a speed control lever (1) of a diesel engine.
A fuel limit actuator (4) is attached to (3), and the fuel limit command switch (2) is set to a fuel limit holding timer.
A fuel limiting control circuit (6) is constituted by being linked to the fuel limiting actuator (4) via (5) so as to be capable of command operation, and the speed control lever (1) is moved from a low speed position (L) side to a high speed. Position (H)
When the fuel limiting command switch (2) is operated at the fuel limiting command position (M) in the middle of the operation when the fuel limiting command switch (2) is operated toward the side, it is set by the fuel limiting holding timer (5). The fuel limiting actuator (4) continues to advance to the fuel limiting position (J) for the fuel limiting holding time (T1), and the control rack (7) of the fuel injection pump (3) is moved to the fuel limiting position (J). ), The control rack (7) is located at a predetermined high load position (P) set within the high load region (N). When it reaches, the high load position detection switch (8) detects it and activates a fuel restriction allowable timer (9).
Based on the input of the high load detection signal of the switch (8),
From the start of this signal input, the fuel limit allowable time (T2)
Until the passage of time, the fuel limit permission signal is
Limiting holding configured to output to the timer (5), the fuel limit allowable timer (9), the fuel limit allowable time
Before reaching the end point (t3) of (T2), the fuel
The above fuel limitation based on the detection operation of the limitation command switch (2)
Fuel control of the fuel limiting actuator (4) by a holding timer (5)
To the limit position (J) and maintain the fuel limit.
Timer (5) moves its fuel limit actuator (4) to the fuel limit position.
(J) is held for the fuel limit holding time (T1), whereas the fuel limit allowable timer (9)
After the end of the time limit (T2) (t3),
Is based on the detection operation of the fuel limit command switch (2).
The fuel limit operation by the fuel limit holding timer (5)
We will prohibit the operation of the motive device (4) to advance to the fuel limit position (J).
Electrically controlled during rapid acceleration fuel limiting device for a diesel engine, characterized in that the sea urchin configuration.