JPS582433A - Method and system for power control of car-mounted diesel engine - Google Patents

Abstract

PURPOSE:To lessen speed change control frequency in time of climbing the uphill grade and to make it easier, by installing a controller and control rack regulator to control a fuel pump according to signals from the engine speed detector and speed gear control position detector. CONSTITUTION:A control rack regulator 2 and a governor 7 both are installed on a fuel-injection pump 1. An engine speed detector 4 and a speed change control position detector 5 are connected en bloc to a controller 3. When the engine is in full-load running and not yet in a specified gear step, a full-load torque curve is Co. During climbing the uphill grade with a designated gear step by the speed gear, when engine speed gets lowering down, the signal of the control position detector 5 enters the controller 3, forcing the control rack into the fuel increment direction. In this condition, only when an accelerating pedal is treadled, engine's generating torque becomes increased and a shifting of the speed gear for climbing the uphill grade is thus made unnecessary.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an output control method and device for a vehicle tower-mounted diesel engine, and in particular, an output control method that can reduce the frequency of gear change operations during climbing etc. and at the same time facilitate climbing. and devices.

The most energy efficient type of prime mover for a vehicle is a direct current series motor, which has higher torque as the speed decreases.
It has a torque characteristic such that the torque decreases as the speed increases5
However, internal combustion engines generally do not have the above-mentioned torque characteristics, and therefore it is necessary to equip a vehicle equipped with an internal combustion engine with a large transmission. However, if the equipped transmission is not a continuously variable transmission, the output torque cannot be changed continuously, so the output torque between each gear changes in steps, resulting in the vehicle running. In addition, there are problems in that it is difficult to select the most suitable drive torque for the vehicle, and frequent gear shifting operations are required.

FIG. 1 shows one such example, in which the horizontal axis represents the traveling speed V of the vehicle, and the vertical axis represents the driving force T generated by the transmission output shaft. In addition, I is the driving force curve in the first gear of the transmission, H is the same in the second gear, and 1 to ■ are the driving force curves in the third, fourth, and fifth gears (l high speed), respectively. be. As can be seen from this figure, the driving force curves at each gear stage are far apart from each other except for between 4th and 5th gears, so, for example, the running resistance of the vehicle is between TI and T3. If it was,
The vehicle driver must operate the transmission to second gear and drive the vehicle, but in this case, the driving force becomes excessive and fuel consumption increases more than necessary.

This phenomenon is especially common when pitching. For example, if a vehicle running in third gear is decelerated due to an increase in running resistance and the vehicle speed becomes further lower than speed v8, the running resistance of the vehicle at that time is between T and T3. Even if this occurs, the driver will have to downshift to second gear and further depress the accelerator pedal to accelerate.

In order to suppress such wasteful fuel consumption and eliminate the need for frequent gear shifting operations, it would be good if the change in the driving force of the transmission output shaft became a continuous curve like the two-dot chain line A in Figure 1. Such a change in driving force can only be realized by a continuously variable transmission such as a torque converter.

Therefore, in order to achieve driving force characteristics similar to the driving force change A described above using a manual transmission, it is necessary to use a multi-speed transmission with as many as 10 gears, or to change the Tagata torque characteristics of the engine itself. Although there is a need for improvement, the former method using a multi-stage transmission is not preferred because it requires more number of gear shifting operations and also significantly increases the weight of the transmission. Also, since fuel is wasted while changing the transmission, it is better to reduce the number of times the transmission is changed. Therefore, if the torque characteristics of the transmission output shaft can be approximated to the characteristic A described above by improving the output characteristics of the engine itself, it is possible to reduce the number of gear shifting operations, reduce wasteful fuel consumption, and achieve smooth running. It should be.

Figure 2 shows the conditions necessary for the purpose described above as changes in the torque of the transmission output shaft.
represents the output torque change in the second speed, and T represents the output torque change in the third speed.

The conditions for these torque changes to be close to the characteristic A described above are: (1) the torque fluctuation (torque rise) TR at each gear is large; (10) the maximum torque at each gear and the preceding gear It is necessary that the difference Δ between the minimum torque at and In terms of operability and economy, (a) expensive and low transmission efficiency;
b Avoiding the use of expensive torque converters, (b
) Avoid using manual multi-speed transmissions (at least 10 speeds or more).

When these conditions are added, it is clear that in order to satisfy the above (1) to (iii), it is necessary to improve the output characteristics of the engine body rather than the transmission structure. In particular, in conventional diesel engines (both non-supercharged and supercharged), in order to meet the above requirements, the torque increases in the low speed range.
Since the torque characteristics were not met, there was a need to improve this.

Figure 3 is for explaining the purpose and principle of this book.
This is part of the driving performance diagram of the vehicle shown in □. In the figure, the horizontal axis represents the vehicle speed V, and the vertical axis represents the driving force T of the transmission output shaft. Further, a solid curve C1 indicates, for example, a change in the output torque of the fifth gear of a manual six-speed transmission,
It is assumed that a solid curve C2 indicates a change in the output torque of the sixth gear of the same transmission. (Generally, a power unit consisting of a combination of a manual 5- or 6-speed transmission and a diesel engine has such driving force torque characteristics.) A vehicle equipped with a power unit having driving force characteristics as shown in the figure. For example, when the road slope becomes steep while the vehicle is in sixth gear and fully loaded, the vehicle speed V begins to decrease, and as the vehicle speed decreases, the driving force increases along curve C2 in the direction of arrow a. If the load resistance is still greater than the propulsion shaft driving force even when the vehicle speed reaches Vu, the driver
In step a, the transmission must be shifted down to 5th gear to increase the driving force, but the load resistance at that time is an intermediate value between the small driving force in 5th gear and the maximum driving force in 6th gear. If so, by shifting down, the increased driving force can be applied to the propulsion shaft, and the vehicle speed can be increased again. However, this is undesirable because extra fuel is consumed when downshifting.

Therefore, in the present invention, in order to eliminate the need for such a downshift, the propulsion shaft drive force curve during full load running at a fixed gear is connected to the drive force curve at the previous gear, for example, as shown in B. The aim is to increase the engine-generated torque itself toward lower speeds so that the engine speed can be increased. Therefore,
According to the present invention, the amount of fuel supplied, which has heretofore been adjusted independently of the transmission, is changed in conjunction with the transmission, making it possible to control the output in accordance with the driving conditions. Mayu ~ According to the output control method of the present invention, the torque rise in the gear is increased, and driving performance similar to that of a continuously variable transmission vehicle can be obtained even with a manual transmission with a relatively small number of gears. This also eliminates the need for frequent gear shifting operations, resulting in reduced fuel consumption and economical driving.

FIG. 4 is an engine torque diagram showing the principle of the method of the present invention, in which the vertical axis shows the torque generated by the engine, and the horizontal axis shows the engine rotation speed. In addition, in the same figure, the solid line curve Co
is the full-load torque curve of a commonly used engine. Also, curve Cx indicates, for example, when the engine starts operating in the 5th gear of a manual 6-speed transmission.

The following curve represents the full-load torque characteristic generated by the engine, and Cy is a curve representing the full-load torque characteristic generated by the engine when the transmission is operated in the sixth gear. Curves Cx, Cy
is generated from the engine only when the vehicle is running by the output control device of the present invention.

The propulsion torque in the low speed range is greater than that of the conventional engine by an amount of increase C, so that the propulsion shaft torque characteristic as shown in B in FIG. 3 can be achieved.

Next, embodiments of the present invention will be described with reference to FIGS. 5 to 8.

FIGS. 5 to 8 show an embodiment of a mourning apparatus for carrying out the method of the present invention. The apparatus of the present invention shown in the embodiment of the figure includes a light control rack regulator 2. a controller 3 for controlling the control rack regulator 2;
．． It consists of equipment such as an engine rotation speed detector 4 and an operation position detector 52 of a transmission (not shown), which are electrically or mechanically connected to the controller 3. In addition, in Figure 5,
7 is a public knowledge governor, and 8 is a timer.

Reference numeral 9 denotes a control lever, 1 (1: operation lot, te = control rack adjuster 2 is attached to the opposite end of the fuel injection pump 1 from the governor device side, as shown in Figs. 6 to 8). The casing 11 is provided with a control rack adjustment member 12 aligned with one control rack of the fuel injection pump 1.The casing 11 includes a cylinder 13 for moving the control rack adjustment member 12 in the axial direction. A lever 15 is pivotally mounted within the casing 11 to connect the control rack adjustment member 12 and the piston rod 14 of the cylinder 13. Inside the casing 11 is a lever 15 for guiding the control rack adjustment member 12. A cover plate 17 for pressing the split sleeve 16 is fastened to the casing 11.The cover plate 17 has a movable stopper 18 for adjusting the most retracted position of the control rack adjustment member 12. is screwed in.

In this embodiment, the control rack adjuster 2 is used to change the maximum fuel supply position for one control rack (the left position in FIG. 9 and governor 7
When one person in the control rack operated toward the left in FIG. 6 (in the fuel increasing direction) hits the control rack adjustment member 12 through the
(not shown).

Next, the operation of each part of the apparatus configured as described above will be explained, and at the same time, the relationship between the apparatus and the method of the present invention will be explained with reference to FIG. (In the following explanation, it is assumed that the transmission mounted on the vehicle is, for example, a 6-speed manual transmission.
It should be noted that any manual transmission may be used, and the number of gears is not a particularly limiting element in the present invention. ) When the engine is operating at full load and the transmission is not in a specifically designated gear, the control rack adjustment member 12 is positioned at position xo in FIG. (to the left), the control rack adjustment member 1 is in this position KO.
2, no more fuel is supplied to the engine. The characteristic curve for this position X (engine full load torque at k) is C in FIG.

It is. While the transmission (not shown) is running at a specifically designated gear, for example, 5th gear, when the engine speed drops below Nel, a signal is sent from the operating position detector 5 to the controller 6, and the controller 6 is activated. 6 controls the cylinder 13 to retract the control rack adjustment member 12 to a position to the left of X6, for example,
When one person holds the control rack, it is propelled in the direction of increasing fuel.

When the accelerator pedal is fully depressed in this state, the control rack adjustment member 12 moves to position X11 in FIG.
The fuel injection pump supplies fuel to the engine (not shown) so that the engine (not shown) generates a torque characteristic Cx when the control rack 1A is propelled to its maximum fuel position. However, the engine speed is Ne
1, the controller 3 pushes the control rack adjusting member toward the right in FIG. 6, reducing the fuel supply to the engine.

As a result, the fuel is controlled so that the torque characteristics of the engine match the original Co.

Therefore, for example, in 5th or 6th gear, when the engine speed drops to below Nel or Freeze 3 while the engine is running under full load, the torque generated by the engine will increase just by pressing the accelerator pedal. Therefore, there is no need to downshift the transmission, which makes driving easier and prevents increased fuel consumption due to downshifting.

FIG. 9 shows another embodiment of the present invention, in which a supercharging device 19 is added to increase the engine-generated torque in the female engine low-speed range compared to the torque in the high-speed range. ing. This supercharging device 19 also serves as a part of a conventional air brake device, and a compressor 20 for the air brake
and an air reservoir 21, and further includes a supercharging pipe 24 that connects the air reservoir 21 and an intake pipe 23 of an engine 22, and a supercharging valve 25 provided in the supercharging pipe 24.

The supercharging valve 25 is a flow rate control and pressure regulating valve that is opened and closed by the controller 5, and when the supercharging valve 25 is opened, the engine 22 is supercharged. In the embodiment described above, the supercharging valve 25 is opened when the engine speed is below 8 or Ne3 and the vehicle is running with the transmission in the 5th or 6th gear, and when the engine speed decreases. The controller 3 controls the opening degree accordingly.・And the engine speed is Nel
Otherwise, it is closed during operation at NH or above, and the only intake air to the engine is intake air S from the air cleaner.
will operate without supercharging. Therefore, the full load torque curve of the engine is as shown in FIG.

(In order to reduce the power consumption of the compressor 20, a separate compressor is provided that utilizes the exhaust energy of the engine 22, and an auxiliary air reservoir is provided to recover the exhaust energy as compressed air when the engine rotates at high speed. ) The above is an example for variable control of the maximum fuel supply amount under full load, but even under partial load, the generated torque in the medium and low speed range is increased more than the generated torque in the high speed range. For this purpose, the conventional governor is not suitable, and the control rack regulator 2 of the present invention must be used in place of the conventional governor.

The embodiment shown in FIG. 10 shows an example in which the control rack adjuster 2 described above is used in place of the conventional governor. In this example, as shown in FIG. 11, the control rack adjustment member 12 is connected to the control rack 1A, and the controller 3 includes an accelerator pedal operation amount detector 6 for detecting the amount of rotation of the accelerator pedal 26.・The output signal is applied and spreads. Therefore, while driving in any gear.

When the engine speed becomes lower than the predetermined speed, the controller 3Fi
Control rack adjustment member, 12t-
The control rack operation amount is controlled through the control rack.

The embodiment shown in FIG. 12 shows an example in which the method of the present invention is applied to an exhaust turbocharged engine. In this example, the first
A low-speed range supercharger 19A having the same configuration as the supercharger of the embodiment shown in FIG.
8 is connected to the intake pipe 23 through a valve port. The compressor discharge port of the high-speed range supercharger 27 is also connected to the suction side of the compressor 20 of the low-speed range supercharger 19A via a branch pipe 29. A supercharging valve 30 is provided in the pipe 28, and the valve 30
is controlled by the controller 3.

In the above configuration, in the low speed range of the engine 22, the supercharging valve 25
When the supercharging valve 30 is opened, the supercharging valve 30 is also opened, but only the supercharging valve 60 is opened in the high speed range of the engine.

Further, since the flow rate and pressure of the supercharging valve 25 are set higher than those of the supercharging valve 30, the degree of supercharging in the low speed range of the engine is higher than the degree of supercharging in the high speed range. Part of the exhaust gas recovery energy when the engine is at high speed is directly supercharged to the engine, but the rest is sent to the low speed range supercharging device 19.
The energy is stored as replenishment energy to the A and air brake systems. Therefore, the torque generated in the low speed range can be made larger than the torque generated in the high speed range, and the torque characteristics of the engine and the torque characteristics of the vehicle's propulsion shaft can be changed to Cx and Cy in Fig. 4 and B in Fig. 5. It can be a characteristic.

As described above, according to the present invention, it is possible to control the output of a tower-mounted diesel engine to suit the running of all vehicles, thereby reducing the frequency of gear change operations, for example, when climbing, and reducing fuel consumption. can be achieved.

[Brief explanation of the drawing]

Figure 1 is a driving performance diagram showing the relationship between the vehicle's propulsion shaft driving force and vehicle speed, Figure 2 is a diagram showing the characteristics necessary for propulsion and driving force, and Figure 3 is the same as Figure 2. FIG. 4 is a diagram for explaining the characteristics of the propulsion shaft driving force obtained by the method and apparatus of the present invention, and FIG. The diagrams shown in FIGS. 5 to 8 are schematic diagrams of a first embodiment of the apparatus of the present invention, FIG. 6 is an enlarged longitudinal cross-sectional view of a part of FIG. 5, and FIG. 6 is a cross-sectional view taken along the arrow ■-■, FIG. 8 is a plan view of a part of FIG. 6, and FIG. 9 is a schematic diagram of a second embodiment of the device of the present invention.
FIG. 10 is a schematic diagram of a third embodiment of the device of the present invention; FIG.
The figure is an enlarged vertical sectional view of a part of FIG. 10, and FIG. 12 is a schematic diagram of a fourth embodiment of the apparatus of the present invention. 1; Fuel injection pump, 1A; Control rack, 2;
Control rack regulator, 3; controller. 4; Engine speed detector, 5; Transmission operation position detector, 6
Accelerator pedal operation amount detector, 19; Supercharging device, 20; Compressor, 21; Air reservoir, 25; Supercharging valve,'19A;
Low speed range supercharger, 26; Accelerator pedal, 27; High speed range supercharger, 30; Supercharging valve. Agent Patent Attorney Tsuji San Department Figure 1 Figure 3 l 1-V Figure 2 V -1÷N

Claims (2)

[Claims] (1) A method for controlling the output of a diesel engine mounted on a vehicle, which detects the gear position of the vehicle's transmission and applies special control when the speed of the diesel engine when the gear position is used is below a predetermined rotation speed. For vehicle installation, characterized by increasing the amount of fuel supplied and thereby controlling the fuel supply system of the engine so that the torque generated by the engine in the cough region is larger than the torque generated by the engine outside the region. Diesel engine output control method. (2) A control rack adjuster for positioning the fuel injection pump control rack, a transmission operation position detector for detecting the gear position of the vehicle's transmission, and an engine rotation speed detector for detecting the engine rotation speed. and positioning the control rack at a predetermined position via the control rack adjuster in response to a signal from the transmission operation position detector, and at the same time, in a region where the engine speed is below a predetermined speed, the control An output control device for a diesel engine mounted on a vehicle, comprising: a controller for positioning a rack in a fuel increasing direction from a position corresponding to an area other than the area.