JPH0134710Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a fuel supply device for an engine.

[Prior art]

Conventionally, in engines that use low-quality fuel (heavy oil + light oil), the viscosity of the low-quality fuel is high when starting the engine, so good spray cannot be obtained, resulting in poor starting.

Therefore, as shown in Utility Model Application Publication No. 57-61163,
A low-quality fuel tank and a high-quality fuel tank are provided, and fuel from both tanks can be selectively supplied to the nozzle using a switching valve, so that high-quality fuel is supplied at the time of starting the engine, and low-quality fuel is supplied after the engine is started. A device that has been used for this purpose is known.

[Problem that the invention aims to solve] However, with this device, the low-quality fuel tank and the high-quality fuel tank are separate, so there are problems such as the installation space for the tank becoming wider, and the problem that the low-quality fuel This method requires a means for detecting temperature and two switching valves that are switched in response to the detection signal, resulting in a disadvantage that the cost is high.

The present invention was devised in view of the above circumstances, and its purpose is to provide an engine fuel supply system that can start the engine smoothly, reduce the tank installation space, and further reduce the cost. That's true.

[Means and actions to solve the problem]

The inside of the tank is divided into a first chamber and a second chamber by a partition wall, a heat insulating material is installed on the inner wall of the first chamber, a heat exchanger is installed in the second chamber through which engine cooling water flows, and high-quality fuel in the first chamber is installed. This is an engine fuel supply device connected to a fuel injection pump via a thermo valve that switches between low-quality fuel in the second chamber and the low-quality fuel depending on the temperature of the low-quality fuel, so that high-quality fuel is injected when the engine starts. After startup, low-quality fuel is supplied to the fuel injection pump, the tank can be made smaller, the tank setting space can be narrowed, and since only one thermo valve is required, costs can be reduced.

〔Example〕

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

The tank 1 is divided into first and second chambers 3 and 4 by a partition wall 2.
The first chamber 3 contains high quality fuel (light oil).
Low-quality fuel (heavy oil + light oil) is injected into the second chamber 4 and stored therein, and the first and second chambers 3 and 4 are connected to pipes 8 and 9 equipped with filters 6 and 7 to control the thermovalve 10. 1 and second inlets 10a and 10b, respectively, and an outlet 10c of the thermovalve 10 is connected and communicated with a fuel injection pump 12 through a conduit 11.

A heat insulating material 13 is provided around the inner wall of the first chamber 3, and a heat exchanger 14 is built in the second chamber 4, and the heat exchanger 14 is connected and communicated with the cooling water system of the engine 15. be.

The thermovalve 10 has a first inlet 10a and an outlet 10c communicating with each other when the low-quality fuel temperature is low;
When the temperature is high, the second inlet 10b and the outlet 10c communicate with each other, and when the temperature is intermediate, the first and second inlets 10a and 1
0b is configured to communicate with the outlet 10c, and a thermovalve 16 provided on the inlet side of the heat exchanger 14 is configured to be fully open when the temperature of the low-quality fuel is low, and fully closed when the temperature of the low-quality fuel is high. .

However, since the temperature of the cooling water of the engine 15 is low when the engine is started, the low-quality fuel is also in a low temperature state and is not well sprayed.

At this time, since the thermovalve 10 communicates the first inlet 10a and the outlet 10c, high quality fuel is supplied to the fuel injection pump 12 and is well sprayed, allowing the engine to be started smoothly.

When the engine starts and the coolant temperature rises, the temperature of the low-quality fuel increases, and the thermovalve 10 is switched to a state where the second inlet 10b and the outlet 10c communicate with each other, and the low-quality fuel is supplied to the fuel injection pump 12. Run the engine on low quality fuel.

When the temperature of the cooling water in the engine 15 exceeds a certain temperature, the thermovalve 16 closes and no cooling water is supplied to the heat exchanger 14, preventing the low-quality fuel from reaching a certain temperature. ) is prevented.

Moreover, since there is only one tank 1, it can be installed in a narrow space.

Further, since the heat of the high-temperature low-quality fuel is not transferred into the first chamber 3, the high-quality fuel is not heated to a high temperature.

Also, depending on the temperature of low quality fuel, thermo valve 1
Since 0 is switched, there is no need to provide a temperature sensor, etc., and the cost can be reduced.

[Effect of idea]

When starting the engine, the temperature of the engine cooling water is low and the temperature of the low-quality fuel is low, so the thermo valve 10
is switched and high-quality fuel is supplied to the fuel injection pump 12.
When the engine cooling water temperature rises after the engine starts, the heat exchanger 14 exchanges heat with the low-quality fuel to reach a high temperature, and the thermovalve 10 switches to supply the low-quality fuel to the fuel injection pump 12.

Therefore, the engine can be started smoothly, and after starting, the engine can be operated with low-quality fuel.

Furthermore, since the inside of the tank 1 is divided into a first chamber 3 and a second chamber 4 by the partition wall 2, the tank 1 can be made smaller and can be installed in a narrow tank installation space.

Further, since it is sufficient to provide only one thermovalve 10 that switches and operates depending on the temperature of the low-quality fuel, and there is no need to provide a temperature detection means for detecting the temperature of the low-quality fuel, costs can be reduced.

In addition, since the heat insulating material 13 is provided on the inner wall of the first chamber 3, the heat in the second chamber 4 is not transferred into the first chamber 3, and the high quality fuel in the first chamber 3 is transferred to the second chamber 3. There is no heating and temperature rise due to the heat of the low-quality fuel in the chamber 4.

[Brief explanation of the drawing]

The drawings are configuration explanatory diagrams showing an embodiment of the present invention. 1 is the tank, 2 is the bulkhead, 3 and 4 are the first and second
10 is a thermo valve, 12 is a fuel injection pump, 13 is a heat insulator, and 14 is a heat exchanger.

Claims (1)

[Scope of utility model registration request] The tank 1 is divided into first and second chambers 3 and 4 by a partition wall 2.
The first chamber 3 stores high quality fuel and the second chamber 4 stores low quality fuel.
A heat insulating material 13 is attached to the inner wall of the chamber, and a heat exchanger 14 is installed in the second chamber 4 through which engine cooling water flows. The first chamber 3 and the pipe line 11 are connected to each other, and when the temperature of the low-quality fuel is high, the second chamber 4 and the pipe line 11 are connected to each other through a thermovalve 10 which is switched to communicate with the pipe line 11. 11 is connected to a fuel injection pump 12.