JPS645088Y2 - - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a fuel supply system for a marine engine.

FIG. 1 shows a conventional fuel supply system of this type. In the figure, 1 is a fuel storage tank used for the engine;
2 mixes the surplus of supplied fuel and the consumed supply,
This is a separation cylinder that separates vapor. In order to measure fuel consumption, the consumed supply passes through a strainer 4 and a flow meter 3, passes through a separation tube 2, passes through a supply pipe 12, is suctioned and pressurized by a supply pump 5, and is pumped by a fuel oil heater 6. After being heated, it is passed through a strainer 7 and passed through a supply pipe 13 to a fuel injection pump 9 attached to an engine 8.
sent to. This part of the fuel oil is consumed by the engine, and the surplus oil returns to the separation cylinder 2 from the return pipe 14 via the pressure regulating valve 10.

In this device, if the strainer 4 and flow meter 3 become contaminated and the internal flow resistance increases, the amount supplied from the tank 1 will decrease. When the strainer 4 and flowmeter 3 are clean, the liquid level in the separation tube 2 is at the normal liquid level _L1 , but when these become contaminated, it gradually decreases and finally reaches _L3 . In this case, air enters the supply pipe 12 from the air vent pipe in the upper part of the separation cylinder 2, the supply of fuel oil is cut off, and the engine in operation is stopped. Sudden stoppage of a ship's propulsion engine, power generation engine, etc. is extremely dangerous in terms of ship maintenance.

Measurement of fuel consumption by flow meter 3 and strainer 4
Although the primary flow of fuel due to this is also important, the engine stoppage accident mentioned above must be prevented even at the cost of these.

The flow state of fluid is generally detected by changing the supply pressure or by changing the differential pressure between the inlet and outlet of a strainer, but it is difficult to detect minute changes. By the time a pressure change is detected using these methods, the engine is almost on the verge of stopping, and it is too late to take any countermeasures.

The purpose of the present invention is to focus on the above-mentioned points and provide a fuel supply device that can sensitively detect the degree of contamination of the flowmeter 3 and strainer 4 to prevent fuel supply from being stopped. , a strainer from the tank, a flow meter, a separation cylinder for separating fuel and air, and a supply pump are arranged in this order in a supply pipe between the fuel storage tank and the fuel injection pump to supply fuel to the fuel injection pump; In a marine engine fuel supply system in which excess fuel is returned to the separation cylinder, a liquid level detector for detecting changes in the liquid level in the separation cylinder, a strainer and a flow meter are short-circuited to separate the fuel storage tank from the above. The present invention is equipped with a bypass path connecting the cylinder and an on-off valve that opens and closes the bypass path in response to a detection signal from the liquid level detector.

In this case, since changes in the liquid level in the separation tube respond sensitively to changes in the flow rate in the supply pipe 11, it is possible to detect this and prevent supply stoppage.

The present invention can be applied to fuel supply systems for main engines, generators, and boilers.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 2 is an explanatory diagram showing one embodiment of the device according to the present invention.

In the figure, numerals 1 to 14 indicate the same members as in FIG. 1 showing the conventional example.

A bypass passage 15 connects the fuel storage tank 1 and the separation cylinder 2 by short-circuiting the flow meter 3 and the strainer 4.

Reference numeral 18 denotes an automatic opening valve, ie, an on-off valve, for opening the bypass passage 15 in response to a liquid level detection signal of the separation cylinder 2.

16, when the liquid level in the separation cylinder 2 falls and reaches L ₂ ,
A liquid level detector 17 detects this and sends a signal to the automatic control panel 19, and 17 is a pressure balancing tube between the liquid level detector 16 and the separation tube 2. The automatic control panel 19 is provided with a reset button for closing the automatic opening/closing valve 18 and returning to the normal state again after the warning light, flowmeter 3, and strainer 4 have been returned to normal.

Reference numeral 20 denotes an alarm panel located at a remote location, which can notify of abnormalities in the flowmeter 3 and strainer 4.

The operation in the case of the above configuration will be described.

If the flow rate of the supply pipe 11 decreases due to the flow meter 3 and the strainer 4 becoming dirty or broken, the liquid level of the separation tube 2
When _L1 falls and reaches _L2 , the liquid level detector 16 detects this and sends a signal to the automatic control panel 19. This signal is counted for a certain period of time by a timer built into the automatic control panel 19, and after confirming the state of _L2 ,
A signal is sent to the automatic relief valve 18 causing it to open.

Since fuel oil is supplied through the bypass path 15, the liquid level _L2 returns to _L1 again, but the automatic release valve 18 remains open. After cleaning or restoring the flowmeter 3 and strainer 4, the alarm disappears by pressing the reset button on the automatic control panel 19, the automatic release valve 18 is closed, and the system returns to normal.

The above case has the following effects.

Abnormalities in the flow meter 3 and strainer 4 are detected sharply and reliably, the bypass path 15 is opened, and fuel supply is guaranteed.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing a conventional fuel supply device, and FIG. 2 is an explanatory diagram showing an embodiment of the fuel supply device according to the present invention. 1... Fuel storage tank, 2... Separation cylinder, 3...
Flow meter, 4... Strainer, 5... Supply pump, 8...
...Engine, 9...Fuel injection pump, 11, 12, 1
3... Supply pipe, 15... Bypass path, 16... Liquid level detector, 18... Automatic release valve.

Claims (1)

[Scope of utility model registration request] A strainer from the tank, a flow meter, a separation cylinder for separating fuel and air, and a supply pump are arranged in this order in a supply pipe between the fuel storage tank and the fuel injection pump to supply fuel to the fuel injection pump, In a marine engine fuel supply system in which excess fuel is returned to the separation cylinder, a liquid level detector for detecting changes in the liquid level in the separation cylinder, a strainer and a flow meter are short-circuited to separate the fuel storage tank from the above. Bypass path connecting the cylinder,
A fuel supply device comprising an on-off valve that opens and closes the bypass passage based on a detection signal from the liquid level detector.