JPS62101844A - Start control device of in-line fuel injection pump - Google Patents

Abstract

PURPOSE:To start an engine positively in a simple manner so as to eliminate a need for the stepping of an accelerator pedal before starting for improving operations in case of starting the diesel engine by holding a torque cam at an increasing position in fuel feeding. CONSTITUTION:The time when the cranking is started with a starter motor actuated, is detected by a cranking start detecting means 16. And a signal is outputted from a start control means 19 to a torque cam hold means 18 based on the start of the cranking so as to check the rotation of a torque cam for holding the torque cam at the position for an increase in fuel feeding. On the other hand, the time when an engine speed exceeds a specified value, is detected by an engine speed detecting means 17 so as to output a signal from the start control means 19 to the torque cam hold means 18 for releasing the check of the torque cam rotation. This allows the torque cam to be held at the position for an increase in fuel feeding in case of starting an engine so as to start the engine positively in a simple manner.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a starting control device for an in-line fuel injection pump, and more particularly to control of a torque cam.

[Prior art and its problems]

In a diesel engine fuel injection system equipped with an in-line fuel injection pump, a torque cam is rotated as the engine speed increases, and a sensor lever whose tip contacts the circumferential surface of the torque cam rotates the torque cam. The fuel injection amount is adjusted by suppressing excessive movement of the fuel injection pump and changing the stroke of the plunger of the fuel injection pump. The structure of the in-line fuel injection system, which rotates such a torque cam according to the engine speed to control the fuel supply amount and achieve speed control, is described in the Taikun Maintenance Book Supplementary Edition (published in March 1980). )It is described in. The rotation of the torque cam installed in the speed governor of this device is carried out against the idling spring by a flyweight attached to the drive shaft through which the rotation of the crankshaft is transmitted, and a flyweight that lifts in response to centrifugal force. This is accomplished by a sleeve that moves in the direction of the drive shaft, a tension lever that swings against the governor spring as the sleeve moves, and a ronde that converts the swing of the tension lever into rotational motion of a torque cam.

By the way, in a diesel engine, the amount of fuel injected per stroke when starting is required to be greater than the amount of fuel injected during idling or high speed rotation, and in order to achieve this, the tip of the sensor lever is brought into contact. A starting notch is formed on the edge of the torque cam's circumferential surface, into which the tip of the sensor lever fits.This is done because starting requires a lot of fuel. This is to increase the swing range of the sensor lever and to enable displacement of the control rack until the desired amount of starting fuel is obtained. In this case, the driver depresses the accelerator pedal fully before starting the engine, and while the drive shaft is not yet rotating, engages the tip m of the sensor lever with the notch of the fuel increase position near torque cam, and then closes the control rack. After moving to the maximum amount, cranking is started.As long as the accelerator pedal is depressed to the maximum, the sensor lever remains engaged deep in the notch of the torque cam, and starting is performed with the predetermined maximum amount of fuel supply. When you release the accelerator pedal after confirming that the engine has started, the floating lever and guide lever work together to move the control rack in the direction of fuel reduction.The return movement of the control rack causes the sensor lever to turn off the torque cam. Once removed from the notch, the rotating drive shaft lifts the flyweight and rotates the torque cam as described above. In this state, even when the accelerator pedal is depressed to the maximum, the tip of the sensor lever does not touch the circumference of the torque cam. As a result, further rocking of the sensor lever is prevented, and the full-throttle injection amount at idling rotation or engine rotation required for driving is defined, and speed control is performed at that rotation speed.

With the in-line fuel injection system that operates as described above, in order to obtain the amount of starting fuel, it is necessary to engage the sensor lever with the notch of the torque cam as described above, and this operation is performed by the operating manual. etc. are listed. In other words, if you start cranking without fully depressing the accelerator pedal before starting, the torque cam will rotate due to the rotation of the drive shaft, and the sensor lever will come into contact with the circumferential surface without engaging the notch, causing the control rank to start. This is because the movement in the direction of increasing the amount of fuel necessary for this will be blocked.

However, depending on the driver, if the driver forgets or does not know how to press the accelerator pedal before starting, the driver may not be able to start smoothly, and if the outside temperature is low, starting may become impossible. be.

[Purpose of the invention]

The present invention has been made in view of the above-mentioned problems, and its purpose is to prevent a gasoline engine from being unable to start due to an erroneous operation such as forgetting to press the accelerator pedal before starting the diesel engine. To provide a starting control device for an in-line fuel injection pump that allows a starting operation to be performed with the same feeling as when starting.

[Structure of the invention]

The features of the in-line fuel injection pump start control device of the present invention are as follows. In an in-line fuel injection pump, cranking start detection means detects when engine cranking has started, engine rotation speed detection means detects engine rotation speed, and holds a torque cam in a fuel increase position at the time of starting. and a starting control means for instructing the torque cam holding means to hold the torque cam at a fuel increase position at the time of starting from cranking at the time of engine starting until the engine speed reaches a predetermined number of rotations. This means that it is equipped with the following.

[For production]

Before starting, the torque cam is not rotated and is at the fuel increase position. When the starter motor is rotated, the occurrence of cranking is detected by the cranking start detection means. The start control means receives the cranking start signal and outputs a signal to the torque cam holding means to prevent rotation of the torque cam, so that the torque cam is held at the fuel increase position.

The sensor lever is placed in a state where it can be engaged with the notch of the torque cam, and the control rack can be displaced in accordance with the operation of the accelerator pedal within the swingable range of the sensor lever. Therefore, an amount larger than the full-throttle injection amount during idling or high-speed rotation can be injected as the starting fuel amount desired by the driver.

When the engine speed detection means detects that the engine speed has become higher than a predetermined speed, the start control means receives the signal and causes the torque cam holding means to prevent rotation of the torque cam. Outputs a signal indicating that it is to be released. At that time, the driver confirms that the engine is revving up and releases the accelerator pedal, which causes the sensor lever to disengage from the notch in the torque cam, and as a result, the torque cam rotates due to the operation of the flyweight, etc., which is lifted up by the rotating drive shaft. and becomes the normal speed regulating state.

〔Example〕

Hereinafter, the present invention will be explained in detail based on examples thereof.

FIG. 2 shows a speed governor in a fuel injection device of a diesel engine equipped with an in-line fuel injection pump to which the start control device of the present invention is applied, in which the amount of rotation of the torque cam 1 is changed as the engine speed increases. The amount of movement of the control rack 3 is controlled via the sensor lever 2 whose tip 2a is in contact with the peripheral surface 1a, and the stroke of the plunger 4 of the fuel injection pump is changed to adjust the fuel injection amount.
It's becoming a sea urchin. The torque cam 1 provided in such a speed governor is configured so that when the flyweight 6 attached to the drive shaft 5 lifts due to centrifugal force, the sleeve 8
moves against the idling spring 7, and the tensile lever 10 swings against the governor spring 9, so that it is rotated via the rod 11 that reciprocates in conjunction with this.

Such a torque cam 1 is formed with a notch 1b for increasing the amount of fuel so that the amount of fuel injected per stroke at the time of starting is greater than the amount of full-throttle injection during high-speed rotation,
Control lever 1 is activated by pressing the accelerator pedal.
2, etc., the control rack 3 is movable within the swing range of the sensor lever 2, which can be engaged with the notch 1b. A loft 13 in a torque cam holding means 18, which will be described later, is attached to the torque cam 1 so as to prevent rotation of the torque cam 1.

A starting control device is provided that holds the torque cam 1 at a fuel increase position from cranking to a predetermined rotational speed when starting the engine. As shown in FIG. 1, this includes a cranking start detection means 16 for detecting that engine cranking has started, an engine rotation speed detection means 17 for detecting the engine rotation speed, and a torque cam for detecting the start of engine cranking. a torque cam holding means 18 for holding the fuel increasing position;
There is also a starting control means 19 for instructing the torque cam 1 to maintain the fuel increase position. The cranking start detection means 16 detects when the engine start key is turned and the starter motor starts rotating, and the detected signal is input to the start control means 19. The engine rotation speed detection means 17 constantly detects the increase in rotation speed from cranking, and employs a known rotation speed sensor attached to the crankshaft, etc., and its detection signal is also input to the start control means 19. Ru. The torque cam holding means 18 has a function of holding the torque cam 1 in the fuel increase position at the time of starting, and in this example, when excited with the above-mentioned rod 13 as shown in FIG. This is a magnet device consisting of a solenoid 21 that generates electricity. The starting control means 19 instructs the torque cam holding means 18 to hold the torque cam at the fuel increase position at the time of starting from cranking at the time of engine starting until the engine speed reaches a predetermined number of rotations, When a rotational speed signal is input from the engine rotational speed detection means 17, the rotational speed is compared with a predetermined rotational speed stored in advance in the starting control means 19, and until a rotational speed equal to the predetermined rotational speed is input. , solenoid 2 of torque cam holding means 18
1 is maintained in an excited state. and,
When receiving a rotational speed signal exceeding a predetermined rotational speed, a signal to demagnetize the solenoid 21 is output. Note that the predetermined rotation speed is preferably a value that exceeds the idling rotation speed of the engine to some extent, but any desired value can be selected depending on the engine.

The operation of the starting control device having such a configuration will be described next. Since the drive shaft 5 is not rotating before starting, the flyweight 6 does not lift, and therefore, as shown in Fig. 3 (
As shown in a), the torque cam 1 is also not rotated and is at the fuel increase position. When the driver rotates the starter motor to start cranking, the cranking start detection means detects that cranking has occurred (step 1 in the flowchart of FIG. 4, hereinafter referred to as Sl). The starting control means 19 receives the cranking start signal and outputs a command signal to the torque cam holding means 18 to prevent rotation of the torque cam. That is, the solenoid 21 is energized and the rod 1
3 is restrained, and the torque cam 1 is held at the initial fuel increase position (S2). At this time, drive shaft 5
begins to rotate, and the flyweight 6 begins to lift as shown by the broken line, and the sleeve 8 attempts to move, but the swinging of the tension lever 10 causes the torque cam 1, which is blocked from rotating, to move.
blocked by. Therefore, the sensor lever 2 is placed in a state where it can swing from the position shown by the solid line until it engages with the notch 1b of the torque cam 1 shown by the broken line.

When the outside temperature is low and a large amount of starting fuel is required, such as in a cold region, the accelerator pedal is depressed greatly, the control lever 12 is rotated until it comes into contact with the full speed set bolt 22, and the control lever 12 is rotated via the floating lever 23 or the like. The control rack 3 is then moved in the direction of arrow 24 to increase the amount of fuel. At that time, control rack 3
Since the tip 2a of the sensor lever 2 that is swung by engages with the notch 1b of the torque cam 1, the control rack 3 also moves to that limit. Therefore, the plunger 4 of the fuel injection pump is displaced by the control rack 3 and the pinion 25 that meshes with it, so that the maximum amount of fuel can be injected at the time of starting. In other words, Fig. 5 (
As shown in a) to (d), when the start key is turned on, the solenoid of the torque cam holding means 18 is turned on, and the fuel injection amount is maintained at the maximum depending on the maximum depression of the accelerator pedal during that time. As a result, the engine speed increases rapidly.

When the engine rotation speed detection means detects that the engine rotation speed has become higher than the predetermined rotation speed due to fuel supply (S3), in response to the signal, the start control means 19 causes the torque cam holding means 18 to A signal indicating that the blocking of rotation of 1 is released is output. As a result, the solenoid 21 is demagnetized and the holding of the torque cam 1 at the fuel increase position is released (S4). When engine revving is confirmed, the start key is usually released and the accelerator pedal is also released, and the sensor lever 2 returns to the position shown by the solid line in FIG. 3(a). As a result, as shown in FIG. 3(b), the torque cam 1 rotates about the bin 26 due to the operation of the flyweight 6, which is lifted up by the rotating drive shaft 5. Even when the driver depresses the accelerator pedal, the tip 2a of the sensor lever 2 comes into contact with the circumferential surface 1a of the torque cam 1, and the displacement of the control rack 3 that would cause a large amount of fuel to be injected as at the time of starting does not occur.

Thereafter, the full injection amount during idling or at a desired rotation speed is regulated with the tip 2a of the sensor lever 2 in contact with the circumferential surface 1a of the torque cam 1, and a predetermined speed regulation is performed.

In this embodiment, while the torque cam 1 is held at the fuel increase position by the torque cam holding means 18, the control lever 12 is moved to the full speed set port 22.
Since it is not necessary for the fuel injection amount to be in contact with the accelerator pedal, the fuel injection amount can be arbitrarily selected within the hatched area in FIG. 5(C) depending on the amount of depression of the accelerator pedal. For example, if the pedal is depressed to the maximum, the sensor lever 2 engages with the notch 1b of the torque cam 1, and if the pedal is depressed less than that, the amount of rocking of the sensor lever 2 becomes small. In any case, the control rack 3 is displaced in accordance with the operation of the accelerator pedal within the swingable range of the sensor lever 2, and the amount of starting fuel desired by the driver is injected to start the engine.

〔Effect of the invention〕

As can be seen from the description of the embodiments above, the present invention provides a cranking start detection means, an engine rotation speed detection means, a torque cam holding means, a cranking start detection means, an engine rotation speed detection means, a torque cam holding means, and a period from cranking at engine start until the engine rotation speed reaches a predetermined rotation speed. , and a starting control means for instructing the torque cam holding means to hold the torque cam at the fuel increasing position at the time of starting, so that when cranking is started, the rotation of the torque cam is immediately prevented and the fuel increasing position is maintained; The engine can be started using the amount of fuel used for starting. Therefore, there is no need to fully depress the accelerator pedal and engage the sensor lever with the torque cam notch before starting, and failure to start will occur due to forgetting or not knowing how to depress the accelerator pedal before starting. do not have. As a result, the diesel engine can be started with the same feeling as when starting a gasoline engine.

In addition, the holding force of the torque cam only needs to be small, so
This has the advantage that the torque cam holding means can be made compact.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of the present invention, FIG. 2 is a perspective view of a speed governor in a diesel engine fuel injection system equipped with any type of fuel injection pump to which the present invention is applied, and FIG.
Figures (a) and (b) are explanatory diagrams of the operation of the torque cam and sensor lever, Figure 4 is a flowchart explaining the operation, and Figures 5 (a) to (d) are the operation of the solenoid associated with the operation of the start key, and the fuel FIG. 2 is an explanatory diagram showing the correspondence between a possible range of injection amount and a change in engine speed. 1-) Lukcam 1.16-cranking start detection means,
17-.-Engine rotation speed detection means, 18-) Lukcam holding means, 19-Start control means.

Claims (1)

[Claims] (1) In a row type fuel injection pump, a cranking start detection means detects that engine cranking has started, an engine rotation speed detection means detects the engine rotation speed, and a torque cam increases the amount of fuel when starting. A command is given to the torque cam holding means to hold the torque cam at the starting fuel increase position from cranking at the time of engine starting until the engine rotational speed reaches a predetermined rotational speed. 1. A starting control device for an in-line fuel injection pump, comprising a starting control means.