JP5069807B1 - Fuel supply device for internal combustion engine - Google Patents

Abstract

A fuel supply apparatus that supplies fuel to an engine that uses a mixed fuel in which water is mixed with fuel oil so that the engine can be operated stably even if the fuel oil and water of the mixed fuel are separated. The challenge is to make it.
A mixer 2 for stirring and mixing fuel oil and water is provided in a fuel tank 1. The lower end side of the movable pipe 4 is provided with a conduit 3 whose lower end is disposed near the bottom of the fuel tank 1, a movable pipe 4 having a suction port 7, and a float 5 attached to the upper end side of the movable pipe. When the fuel oil and water in the tank are fully separated under full tank, the suction port 7 is kept at a position higher than the separated water W layer. It was made to be.
[Selection] Figure 1

Description

  The present invention relates to a fuel supply device for an internal combustion engine (hereinafter referred to as an engine) using a mixed fuel (an emulsified fuel obtained by mixing water into light oil or gasoline and stirring to make an emulsion).

  The above-mentioned mixed fuel is used for the purpose of improving engine combustion and reducing nitrogen oxides (NOx). A fuel supply device for an engine using this mixed fuel has been proposed in Patent Documents 1 and 2 below.

  The emulsified fuel supply device disclosed in Patent Document 1 mixes fuel and water supplied from separate tanks with a mixer, warms them with a heater, and sends them to a fuel injection pump.

  Further, the fuel supply control device disclosed in Patent Document 2 once introduces fuel oil and water supplied from separate tanks into a mixing tank, where it is used as a mixed fuel. Then, the mixed fuel is pumped up by a high-pressure pump, and then, by irradiating microwaves, water molecules are vibrated to heat the mixed fuel, and the heated mixed fuel is sent to the fuel injection means. The fuel injection means atomizes it and blows it into the cylinder (combustion chamber) of the engine.

Japanese Utility Model Publication No. 55-69139 JP 2007-239653 A

  The above-described fuel supply device of Patent Document 1 requires a water tank in addition to the fuel tank, and thus is not suitable for automobiles or the like that have a high demand for weight reduction or effective use of a limited space.

  The same applies to the fuel supply control device of Patent Document 2. The device of this patent document 2 is provided with a mixing tank, and the fuel oil and water introduced into the mixing tank are separated during that time when the engine has been stopped for a long time. Only the water accumulated underneath is pumped up, hindering the smooth operation of the engine. The inventor has confirmed this through experiments to be described later.

  Therefore, the present invention has an object to allow fuel and water to be used in the same tank for use, and to ensure stable operation of the engine even when the fuel oil and water of the mixed fuel are separated. Yes.

In order to solve the above problems, in the present invention, a fuel supply device for an internal combustion engine is configured as follows. That is, a fuel tank, a mixer for mixing and stirring of fuel oil and water are placed together in a tank provided inside the fuel tank, a conduit lower end is positioned near the bottom of the fuel tank, an upper end Alternatively, a movable pipe having a suction port near the upper end and a float attached to the upper end side of the movable pipe are provided.

Further, the lower end side of the movable pipe is rotatably connected to the lower part of the conduit, and a passage is formed in which the movable pipe and the hole of the conduit communicate with each other to send fuel in the tank toward the engine. In addition , the movable pipe was undulated according to the displacement of the float accompanying the change in the liquid level in the fuel tank. Furthermore, when the fuel oil and water in the tank are completely separated under full tank, the suction port is kept at a position higher than the separated water layer, and the engine is started. The mixer is driven.

  The movable pipe can be connected to the conduit through a rotary joint (rotary joint).

  In the fuel supply device of the present invention, the movable pipe undulates according to the height displacement of the float due to the increase / decrease of fuel in the fuel tank, and the fuel oil and water of the mixed fuel are separated by the height displacement of the suction port accompanying the undulation. When separating, the inlet is immersed in the fuel layer. For this reason, even if the fuel oil and water of the mixed fuel are separated, only water is not sucked, and at this time, only fuel oil is sucked from the suction port. If the fuel oil and water are not separated, the mixed fuel is sucked.

  The smooth operation of the engine is hindered because the separated water is sucked up and blown into the combustion chamber. When the separated water is inhaled, after the mixed fuel remaining in the supply path from the tank to the fuel injector of the engine is consumed and lost, only water is temporarily injected into the combustion chamber. This causes the engine to stop.

  If the apparatus of the present invention is used, either the fuel oil separated from water or the mixed fuel is sucked up and supplied to the engine at the initial start of the engine, so that the engine does not stop.

  When the engine is started, the mixed fuel in the tank is actuated at the same time to agitate the mixed fuel in the tank. Therefore, even if the engine is started in a state where the fuel oil and water of the mixed fuel are separated, only water will be consumed thereafter. There will be no supply situation.

  In addition, if the engine stop time becomes longer, water in the mixed fuel remaining in the supply path from the tank to the fuel injector of the engine may be separated from the fuel oil. Even if it happens, the engine does not stop because the remaining mixed fuel in the supply path is stirred again by pumping up the fuel oil and flowing in the conduit at the next start.

Sectional drawing which shows an example of the fuel supply apparatus for internal combustion engines of this invention The perspective view of the conduit | pipe and movable pipe connection part by the rotary pipe joint of the fuel supply apparatus of FIG. 1 is a cross-sectional view of a conduit and a movable pipe connecting portion by a rotary pipe joint of the fuel supply device of FIG. Side view showing the inlet installation part of the movable pipe The figure which shows the example which attached the filter to the inlet of a movable pipe

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a fuel supply device for an internal combustion engine according to the present invention will be described below with reference to FIGS. As shown in FIG. 1, a fuel supply device for an internal combustion engine according to the present invention includes a fuel tank 1, a mixer 2 that is provided inside the fuel tank and stirs and mixes fuel oil and water that are put together in the tank, The pipe 3 for sending the fuel in the tank toward the engine (not shown), the movable pipe 4 and the float 5 attached to the upper end side of the movable pipe 4 are combined.

  The conduit 3 has a lower end disposed near the bottom of the fuel tank 1. A movable pipe 4 is rotatably connected to a lower portion of the conduit 3 using a rotary pipe joint (rotary joint) 6.

  The movable pipe 4 has a lower end connected to the rotary joint 6, and the upper end side of the movable pipe 4 moves closer to the bottom of the fuel tank 1 in a state where the movable pipe 4 is laid down to the maximum.

  The movable pipe 4 has a suction port 7 at or near the upper end. Fuel in the tank is sucked from the suction port 7, and the fuel is supplied to the engine through the conduit 3.

  The rotary joint 6 is a pipe joint having a known structure. For example, as shown in FIG. 3, a sleeve 6c provided on one of the fixed member 6a and the movable member 6b is rotatably inserted into a socket 6d provided on the other, and a cross section is formed on the outer periphery of the sleeve 6c and the outer periphery of the socket 6d. There is known a pipe joint having a structure in which a semicircular ball groove 6e is provided oppositely and a sleeve 6c is prevented from being detached by incorporating a ball 6f into the ball groove, and an inlet of the ball incorporation hole is closed with a plug 6g. A rotary pipe joint having such a structure can be suitably used.

  As shown in FIG. 2, the lower end of the conduit 3 is connected to the fixed member 6a, and the lower end of the movable pipe 4 is connected to the movable member 6b.

  The height of the float 5 changes according to the increase or decrease of the fuel in the fuel tank 1. Due to the displacement, the movable pipe 4 undulates, and the height of the suction port 7 varies with the undulation.

  The inlet 7 of the movable pipe 4 is located at the position of the inlet rather than the layer of water W under the layer of fuel oil F when the fuel oil and water in the fuel tank 1 are completely separated under full tank. Is designed to be kept high. The fuel oil F and the water W are mixed at a ratio of about 7: 3, for example. Based on the mixing ratio, the height position of the water surface and the height position at which the suction port 7 should be set when the fuel oil F and the water W are completely separated under a full tank are obtained.

  The float 5 rises to the movable upper limit position when the fuel tank 1 is full, but need not always float on the liquid level of the fuel in the tank, and sinks into the fuel when the fuel tank 1 is full. It doesn't matter.

  The float 5 is in contact with the bottom of the fuel tank 1 when the fuel tank 1 is almost empty and the movable pipe 4 is laid down to the maximum, and in this state, the suction port 7 is held above the lower limit height position. Those designed as described above are preferred.

  The lower limit height position mentioned here is above the water layer (water layer separated from fuel oil) that is assumed to remain in the tank under the condition that the float 5 is in contact with the bottom of the fuel tank 1. is there.

Reference numeral 8 in FIG. 1 denotes a stopper that regulates the rising of the movable pipe 4 before the movable pipe 4 assumes a vertical posture. By restricting the standing posture by the stopper 8, the movable pipe 4 is prevented from falling in the direction opposite to the falling direction in FIG. A structure in which the same purpose can be achieved regardless of which side the movable pipe 4 falls down is not necessary.

  The mixer 2 is driven based on an engine start signal. Since the fuel oil and water in the fuel tank 1 are inevitably separated when the engine stop time becomes long, the mixer 2 performs agitation.

  As is well known, fuel is supplied to the engine by a pumping system (not shown) in a direct injection type diesel engine, and by a suction system using negative pressure in a gasoline engine having a carburetor. The fuel supply apparatus of the present invention can be configured by improving a known engine fuel tank.

  A filter 9 may be attached to the suction port 7 of the movable pipe 4 as shown in FIG. Since a filter is built in front of the fuel injection pump and carburetor of the engine, the filter 9 is not indispensable, but if it does not increase the fuel suction resistance (somewhat coarser), the filter 9 is installed. It is good to do.

  When the fuel supply device of the present invention configured as described above is used, the movable pipe 4 undulates according to the increase or decrease of the fuel in the fuel tank 1 due to the buoyancy of the float 5, and the height of the suction port 7 increases with the undulation. The position fluctuates.

  By this operation, when the fuel oil F and the water W injected into the fuel tank 1 are separated, the suction port 7 is always held at a position where it is immersed in the layer of the fuel oil F. Therefore, only water is not inhaled in any situation, and the trouble of engine stop due to inhalation of only water does not occur.

  The fuel tank of the commercial vehicle (Mazda, diesel truck, KC-SD2AT prime mover model R2) is changed to the one having the fuel supply device of the present invention, and the ratio of light oil and water to the fuel tank is 2/3: 1/3 The mixed fuel mixed in was put in, and immediately after that, the engine was started and it was confirmed that the engine moved with the mixed fuel. Next, the engine was stopped, left in the stopped state for 1 week, 2 weeks, and 1 month, and then restarted.

  This test was carried out in two forms: when using the fuel supply device of the present invention and when using a conventional fuel tank originally mounted on a vehicle. After starting, the engine moved for a short time and stopped.

  The engine stopped because the separated water was sucked up at the beginning of the start, and the water was blown into the combustion chamber after the mixed fuel remaining in the supply path from the tank to the engine fuel injector was consumed. It is.

  On the other hand, in the automobile using the fuel supply device of the present invention, the trouble of engine stop did not occur. Even after that, the automobile equipped with the fuel supply device of the present invention has been used continuously for 3 years, but there is still no trouble of engine stoppage, and the highway can be run without any trouble.

DESCRIPTION OF SYMBOLS 1 Fuel tank 2 Mixer 3 Conduit 4 Movable pipe 5 Float 6 Rotary joint 6a Fixed member 6b Movable member 6c Sleeve 6d Socket 6e Ball groove 6f Ball 6g Plug 7 Suction port 8 Stopper 9 Filter F Fuel oil W Water

Claims (2)

A fuel tank (1), a mixer (2) for mixing and stirring inside provided with together encased fuel oil tank of the fuel tank (F) and the water (W), the lower end of the fuel tank ( A conduit (3) disposed near the bottom of 1), a movable pipe (4) having a suction port (7) at the upper end or near the upper end, and a float (5) attached to the upper end side of the movable pipe,
The movable pipe (4) is pivotally connected to the lower part of the conduit (3) at the lower end , and the hole of the movable pipe (4) and the conduit (3) communicate with each other so that the fuel in the tank is supplied to the engine. is passage configured to feed towards its movable pipe (4) is undulating in response to displacement of the float (5) associated with the fuel increase and decrease of the fuel tank (1) in the fuel oil in the tank and water full under The suction port (7) is kept at a higher position than the separated water (W) layer when completely separated at the same time, and the mixer (2) A fuel supply device for an internal combustion engine that is driven. It is assumed that the float (5) contacts the bottom of the fuel tank (1) when the movable pipe (4) falls to the maximum, and the inlet (7) remains in the fuel tank in that state. The fuel supply device for an internal combustion engine according to claim 1, wherein the fuel supply device is held above a water layer to be formed .

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