JPH109081A - Device type fuel injection pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To navigate a ship without stopping an engine when a electric system is damaged by providing with a back-up power supply independently from a main power supply as the operating power supply for a solenoid valve for opening a duel passage at the time of current-carrying, and closing the fuel passage at the time of non-current-carrying. SOLUTION: In the divided fuel injection pump of a ship engine, the discharge port 14c of a fuel passage 14b is communicated and separated with/from the discharge port 17b of a pump cylinder body 17, fuel floes from the discharge port 17b into a fuel discharge passage 1c at the time of communication, and fuel is discharged from a delivery valve 19 to a fuel injection valve. The valve element 18a of a fuel cut valve 18 is interposed in a fuel intake passage 1b freely to move in advance and retreat, the valve 18 is moved to an valve opening side at the time of current-carrying, and current is supplied to the fuel cut valve 18 from a main power supply through a main circuit. When the main power supply is damaged, voltage is applied from a back-up power supply, and opening of the fuel cut valve 18 is ensured.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a distribution type fuel injection pump particularly used for a marine engine, and more particularly to an emergency operation structure of a solenoid valve for opening and closing a fuel passage.

[0002]

2. Description of the Related Art Conventionally, a distribution type fuel injection pump having a feed pump and a plunger pump which reciprocates in synchronization with the rotation of the engine is known, and a plunger is provided from a fuel gallery for storing fuel discharged from the feed pump. Solenoid valve (magnet valve) in the fuel passage to the pump
It is publicly known that the fuel cut valve is interposed and the fuel passage is opened and closed by the fuel cut valve. Conventionally, the power supply for operating the fuel cut valve is a battery mounted for starting the engine or for supplying power to various electric systems (alarm lamps and the like) in the ship. The fuel cut valve closes immediately during a normal engine stop operation,
The fuel supply from the fuel injection pump to the fuel injection valve is stopped to stop the engine rotation.

[0003] However, if the engine stops and cannot be operated at all in the event of a failure of the electric system, etc., movement to the evacuation area,
Since it is not possible to drive the air conditioner, we want to secure a certain amount of engine rotation. In a fuel injection pump for a vehicle, as disclosed in Japanese Patent Publication No. 61-23385, an electromagnetic valve is provided in a fuel inlet passage to a feed pump, the valve is closed when power is not supplied, and only the orifice is communicated when the valve is closed. On the other hand, the fuel cut valve is configured not to close when the electric system fails, so as to secure a fuel passage from the fuel injection pump to the fuel injection valve. That is, at the time of failure of the electric system, only the orifice is open at the inlet of the fuel injection pump, a small amount of fuel is supplied, and an engine runaway that may occur when a specified fuel is supplied is avoided. At the same time, a certain amount of engine rotation can be secured.

[0004]

However, the fuel injection pump described in the above publication is suitable for a vehicle and employs an electronic governor mechanism. Since the electric motor in the electronic governor obtains power from the battery, the rack for controlling the fuel injection amount in the electronic governor moves to the injection amount reducing side when the electric system fails. That is, a small amount of fuel is supplied to the pump inlet side through the orifice, and the rack moves to the injection amount reducing side, so that the fuel injection amount discharged from the plunger pump is very small. If it is suitable for vehicles, it can secure the engine speed to the minimum and can move to the evacuation center,
If this is applied to a ship, there is a problem that it is not possible to secure an engine driving force sufficient for emergency movement. Conventionally, for marine applications, an electronic governor configuration that prevents the fuel injection amount control rack from moving to the fuel reduction side even in the event of an electrical system failure has been applied to address this problem. The electronic governor has a complicated structure and is used for the above-mentioned vehicles. The electronic governor has a structure that moves to the fuel injection amount reduction side with a decrease in voltage (the rack is controlled by an electric motor, and the electric motor is used if the electric system fails. And the rack is automatically moved to the side where the fuel injection amount is reduced.)

[0005]

DISCLOSURE OF THE INVENTION The present invention provides a distribution type fuel injection pump for use onboard a ship at a low cost so as to obtain a configuration capable of navigating a ship without stopping the engine even when an electric system fails. Such means are used.
First, a feed pump and a plunger pump that reciprocates in rotation in synchronization with engine rotation are provided, and an electromagnetic valve is provided in a fuel passage to the plunger pump. In a distribution type fuel injection pump having a configuration in which a passage is opened and the fuel passage is closed when power is not supplied, a backup power supply is provided separately from a main power supply as an operation power supply for the solenoid valve.

Secondly, in the distribution type fuel injection pump having the above-described structure, a main power switch and a backup power switch are provided, and the backup power switch is turned on in conjunction with the turning on of the main power switch. Configure.

Third, in the distribution type fuel injection pump having the above configuration, the capacity of the backup power supply is made smaller than the capacity of the main power supply, and when the voltage of the main power supply becomes smaller than the voltage of the backup power supply, The power supply for operating the solenoid valve is switched to the backup power supply.

[0008]

Embodiments of the present invention will be described with reference to the accompanying drawings. 1 is a side sectional view showing the internal configuration of a distribution type fuel injection pump, FIG. 2 is an electric circuit diagram of a fuel cut valve, FIG. 3 is an electric circuit diagram showing another embodiment of the same, and FIG. It is a figure which shows the operation | movement control flowchart of the emergency in the fuel cut valve of a circuit structure.

First, the internal structure of the distribution type fuel injection pump will be described with reference to FIG. A camshaft 2 connected to an engine output shaft is supported in the pump housing 1, and a feed pump 3 is provided around the camshaft 2, and a rotation of the camshaft 2 is provided. At the same time, the feed pump 3 is driven to rotate to discharge fuel. The inner end of the camshaft 2 is inserted into a fuel gallery 1a in which the fuel discharged from the feed pump 3 is stored, and a drive gear 4 is fixed to the inner end. The fly weight 5 provided in the gallery 1a is in gear engagement. The flyweight 5 operates with centrifugal force in proportion to the rotation speed of the camshaft 2. A governor lever assembly 6 is disposed in the fuel gallery 1a so as to face the fly weight 5, and a tension lever 7 is rotatably supported by the governor lever assembly 6 so as to be rotatable. Is biased by the governor spring 8 toward the fly weight 5 and is in contact with a governor spindle 5 a protruding from the fly weight 5. In addition,
The other end of the governor spring 8 is connected to a control lever shaft 9, and the control lever shaft 9 is integrated with a control lever 10 that rotates with the operation of the accelerator. That is, the governor spring 8 moves by the accelerator operation, and the position of the tension lever 7 is adjusted.

On the other hand, a cam shaft 13 a of a face cam disk 13 is connected to the inner end of the cam shaft 2 via a cross coupling 11 so as to be able to advance and retreat. A roller 12 is provided outside the portion where the cross coupling 11 is provided, and is in contact with a rotating face cam disk 13. The cam shape causes the face cam disk 13 to move in the axial direction of the cam shaft 2. It is configured to advance and retreat. A plunger pump 14 protrudes from the face cam disk 13 on the side opposite to the cam shaft 13a. The plunger pump 14 is urged toward the face cam disc 13 by a plunger spring 15 disposed in the fuel gallery 1a, and the face cam disc 13 is
2 is applied. Further, in the fuel gallery 1a, a control sleeve 16 is slidably fitted to the plunger pump 14, and the plunger pump 14 is slidably and rotatably fitted in the pump cylinder 17. Have been.

A fuel passage 14 is provided in the plunger pump 14.
b are formed in the axial direction, and a plurality of suction ports 14a, 14a,... I have. The suction port 14a is connected to the plunger pump 14
With the rotation of the pump cylinder 1 from the fuel gallery 1a
The fuel suction passage 1b (drilled in the pump housing 1) which communicates with the inside of the pump housing 7 is communicated or isolated. At the time of communication, the fuel suction passage 1b is connected to the suction port 14
The fuel introduced to a flows through the fuel passage 14b through the plunger chamber 17a formed inside the pump cylinder 17.

The discharge port 14c of the fuel passage 14b is
With the rotation of the plunger pump 14, the pump cylinder 17
The fuel flows into a fuel discharge passage 1c (drilled in the pump housing 1) communicating with the discharge port 17b at the time of communication. The fuel is discharged from the delivery valve 19 disposed at the end of the fuel discharge passage 1c to the fuel injection valve.

A fuel passage 14b formed in the plunger pump 14 communicates with a spill port 14d in the fuel gallery 1a. The spill port 14d
Also, the same number of suction ports 14a are provided, and as the control sleeve 16 slides, it is covered by the control sleeve 16 or opens to the fuel gallery 1a. At the end of the discharge stroke to the delivery valve 19, the spill port 14d is connected to the fuel gallery 1a, and fuel is spilled from the fuel passage 14b to the fuel gallery 1a in order to avoid an excessive increase in the discharge pressure.

The tension lever 7 has an end connected to the control sleeve 16. The rotation of the tension lever 7 causes the control sleeve 1 to rotate.
6 slides and the fuel gallery 1a at the spill port 14d
The fuel injection amount (the amount of fuel sent to the delivery valve 19) is adjusted by adjusting the communication timing with the fuel cell. The position of the control sleeve 16 depends on the tension lever 7
Is changed as the position is set by the rotation operation of the control lever 10 by the accelerator operation. For example, when the engine speed decreases, the tension lever 7 rotates by the operation of the flyweight 5 and the control sleeve 16 is moved. The governor that controls the engine speed to be constant is formed by moving the engine to the fuel injection amount increasing side. The governor mechanism shown in FIG. 1 is not an electronic governor but a mechanical governor mechanism, regardless of the failure of the electric system (in the case of the electronic governor, the governor mechanism moves to the fuel injection amount reduction side due to the failure of the electric system). ), The fuel injection can be maintained, and the engine rotation can be secured.

In the fuel intake passage 1b, a valve element 18a of a fuel cut valve 18 is provided so as to be able to advance and retreat. The fuel cut valve 18 is an electromagnetic valve, and when not energized, the valve body 18a moves to the valve-closing side (closes the fuel intake passage 1b) by a spring force. 1b is closed). As shown in FIG. 2, the fuel cut valve 18 is supplied with power via a main circuit A from a main power supply MB for an electric system mounted on a ship or for starting an engine. MS is a main switch such as a key switch.

If the engine stops at the time of failure of the electric system and restarting is not possible, the navigation of the ship is hindered. If the voltage drops due to a trouble (burnout of the main circuit A, dead battery) on the main power supply MB side,
The valve element 18a of the fuel cut valve 18 closes the fuel intake passage 1b, cannot discharge fuel from the delivery valve 19 to the fuel injection valve, stops the engine, and cannot perform emergency movement. Therefore, the electric circuit B is connected to the fuel cut valve 18 from the backup power supply BB.
Is provided with a sub-switch SS. The sub-switch SS is turned on by a relay circuit while turning on the main switch MS, and is always turned on during navigation. That is, during normal navigation, the fuel cut valve 18
Voltage is applied from the main power supply MB and the backup power supply BB. Then, when the main power supply MB fails, the application of the voltage from the backup power supply BB is maintained, and the opening of the fuel cut valve 18 can be ensured.

In this case, the backup power supply BB is not used because the sub-switch SS is turned off when the vehicle is not traveling, so that power is saved. Also, if the sub-switch SS is set to manual, it is normally turned off and turned on when the main power supply fails.
If the sub-switch SS is forgotten to be turned on, the fuel cut valve 18 will be completely closed, the engine will stop, and the main power supply MB will also fail. No, but sub-switch S
Such a situation does not occur because S is always on during navigation.

In setting the voltage on the backup power supply BB side, a low voltage enough to maintain the holding voltage of the fuel cut valve 18 is sufficient, and the capacity can be kept open for about 1 to 2 hours in an emergency. Is fine. For example, when the main power supply MB is 12V, the backup power supply BB is 3V. Since such a small voltage is sufficient, the backup power supply BB can be covered by a dry battery.

In the electric circuit of the fuel cut valve 18 shown in FIG. 3, a controller C is provided in the electric circuit from the backup power supply BB. The controller C is
The detection signal of the voltage sensor VS disposed in the main circuit A from the main power supply MB to the fuel cut valve 18 is input, and if it is determined that the voltage is lower than a certain level, the backup circuit B
a and Bb are connected, a voltage is applied to the fuel cut valve 18 by the backup power supply BB, and an alarm circuit Bc is also connected, so that an alarm buzzer BZ and a lamp L are connected.
An alarm is issued at. In the electric circuit shown in FIG. 3, since the backup power supply BB and the fuel cut valve 18 are connected only in an emergency, the sub-switch SS is turned off during navigation as described above.
The backup power supply BB can be used for a long time as compared with the configuration in which the power supply voltage N is kept constant.

Referring to FIG. 4, control in the electric circuit shown in FIG. 3 will be described. When the voltage sensor VS detects that the voltage Va in the electric circuit A is equal to or lower than the set pressure Vb (for example, 3 V) of the backup power supply BB, the controller C is operated, and the backup circuits Ba and B are operated as described above.
b and the alarm circuit Bc are connected, the fuel cut valve 18 is opened, and the alarm lamp L and the buzzer BZ are operated.

[0021]

According to the present invention, the distribution type fuel injection pump used particularly for marine vessels is constructed as described above, and has the following effects. First, even when the main power supply side fails, the backup power supply can be turned on to maintain the energized state of the solenoid valve and maintain the open state even when the main power supply side fails, and the fuel passage to the plunger pump is reduced. It is secured and the engine can be stopped. This allows
Continued navigation of ships becomes possible. In this case, the governor can be a mechanical governor not related to the failure of the electric system, and a low-cost distributed fuel injection pump for ships can be provided.

According to the configuration of claim 2, when the main power switch is turned on for navigation, the backup power switch is always turned on.
When the main power supply fails, the backup power supply allows the solenoid valve to automatically maintain the open state without the need to operate the backup power supply switch. Therefore, if the main power supply fails, the backup power supply switch is forgotten to be turned on, the solenoid valve is completely closed, the engine is completely stopped, and then the main power supply is faulty and cannot start. Will not wake up. Conversely, if the main power switch is turned off, the backup power is also turned off automatically, and the user may forget to turn off the backup power when not sailing and consume the backup power without knowing it. Can be avoided.

Further, by adopting the configuration of claim 3,
When the main power supply side fails, the state of the main power supply side is detected, and based on this, it can be automatically switched to the backup power supply side, and the backup power supply can keep the solenoid valve open. Furthermore, the backup power supply is not used during normal times when the main power supply is functioning, so that power is not wasted.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing an internal configuration of a distribution type fuel injection pump.

FIG. 2 is an electric circuit diagram of a fuel cut valve.

FIG. 3 is an electric circuit diagram showing another embodiment.

4 is a diagram showing an emergency operation control flowchart for the fuel cut valve having the electric circuit configuration shown in FIG. 3;

[Explanation of symbols]

 Reference Signs List 1 pump housing 1a fuel gallery 1b fuel suction passage 14 plunger pump 17 pump cylinder 18 fuel cut valve 18a valve body MB main power supply MS main switch BB backup power supply SS sub switch C controller

Claims (3)

[Claims] 1. A feed pump and a plunger pump which reciprocates in rotation in synchronization with engine rotation. An electromagnetic valve is provided in a fuel passage to the plunger pump. In a distribution type fuel injection pump configured to open a passage and close the fuel passage when not energized,
A distribution type fuel injection pump comprising a backup power supply as an operating power supply for the solenoid valve, separately from a main power supply. 2. The distribution type fuel injection pump according to claim 1, further comprising a main power switch and a backup power switch, wherein the backup power switch is turned on in conjunction with the turning on of the main power switch. A distribution type fuel injection pump, 3. The distribution type fuel injection pump according to claim 1, wherein a capacity of said backup power supply is made smaller than a capacity of said main power supply, and when a voltage of said main power supply becomes smaller than a voltage of said backup power supply, A distribution type fuel injection pump characterized in that an operation power supply of the solenoid valve is switched to the backup power supply.