JPH0388953A - Alcohol-mixed fuel supplying device - Google Patents

Abstract

PURPOSE:To supply alcohol-mixed fuel with certain mixing by furnishing an ultrasonic vibrating means which promotes mixing together the gasoline and alcohol using ultrasonic vibration on the way of a discharge path leading from a fuel pump to an injection valve, and decoupling the bond between the alcohol and water. CONSTITUTION:When a high frequency voltage is impressed from outside, piezo elements 21 of an ultrasonic vibrator 19 generate axially oriented ultrasonic vibrations, which are amplified by a horn 24 and transmitted to a vibratary plate 26, and at the same time a balancer accomplishes the vibratory balance with respect to the horn 24. Then this vibratory plate 26 gives ultrasonic vibration to alcohol A coupled with water and the gasoline G flowing in a dia. enlarged part 17A, and for the alcohol A incl. water their mutual bond is decoupled to promote segregation, and thus the gasoline G and pure alcohol A are mixed together uniformly. An alcohol sensor 27 is furnished at the next stage of the vibrator 19, and the alcohol concentration in the hybrid gasoline is sensed, and a signal obtained is passed to an injection amount calculating means, and the fuel injection amount is computed together with the engine revolving speed, suction air amount, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an alcohol mixed fuel supply device for supplying alcohol mixed fuel to an injection valve of an engine.

[Conventional technology]

Recently, alcohol-mixed gasoline has come to be used as a fuel for automobiles instead of pure gasoline. However, alcohol has a strong affinity (binding force) with water and absorbs moisture from the atmosphere. Additionally, if moisture gets into the fuel tank, the upper layer will become a gasoline layer due to the difference in specific gravity between the alcohol and gasoline that have combined moisture.
The lower layer becomes an alcohol layer and separates.

In order to solve such problems with alcohol-mixed gasoline, as shown in Japanese Patent Application Laid-Open No. 56-106053, a first fuel passage for sucking up the fuel (gasoline) in the upper part of the fuel tank, A second fuel passage sucks up fuel (alcohol) from the lower side of the tank, and a second fuel passage that sucks up fuel (alcohol) from the lower part of the tank; A fuel pump is provided in the merging fuel passage after merging the second fuel passage and discharges gasoline and alcohol while mixing and stirring the fuel pump, and the fuel pump is provided in the first fuel passage to make the mixing ratio of gasoline and alcohol approximately equal. It is known that the fuel cell is constructed of a throttle provided in each of the second fuel passages.

[Problems to be Solved by the Invention] However, in the conventional technology described above, gasoline drawn up from the first fuel passage and alcohol drawn up from the second fuel passage are mixed or stirred by a fuel pump. It's just there.

However, if water gets mixed into the alcohol and they bond at one end, the alcohol and water will not separate unless a special external force is applied to break the bond. Therefore, if the water-containing alcohol and gasoline separate into two layers in the fuel tank, stirring with the fuel pump will not
The disadvantage is that the appearance is only that it is on the top, and it is not possible to mix it uniformly.

In addition, if alcohol and gasoline separate as mentioned above, even if the alcohol concentration is detected by an alcohol sensor, it will not be possible to accurately detect the concentration, and there is a risk of false detection. This has the disadvantage that control becomes inaccurate.

Furthermore, alcohol blended gasoline has poor low-temperature vaporization properties compared to genuine gasoline, resulting in poor starting performance during cold starts.On the other hand, due to its low boiling point, it is prone to poor acceleration due to vapor lock during hot starts, where it is highly vaporizable. As a result, there is a drawback that accurate starting performance and acceleration performance cannot be obtained, in addition to the fact that the alcohol concentration is likely to be erroneously detected as described above.

The present invention has been developed in view of the problems of the prior art, and it not only makes alcohol and gasoline appear to be on the upper side, but also destroys the bond between alcohol and water to ensure that the alcohol-mixed fuel is properly mixed. An object of the present invention is to provide a device for supplying alcohol mixed fuel to an injection valve.

[Means for Solving the Problems J] In order to achieve the above object, the present invention provides a fuel tank for storing alcohol mixed fuel, a first fuel suction flow path opening on the upper side of the fuel tank, and a fuel tank for storing alcohol mixed fuel. a second fuel suction flow path opening to the lower side of the tank; Second
Alcohol mixed fuel supply consisting of a fuel pump that discharges fuel sucked in through a fuel suction flow path, and an injection valve that is provided in the middle of the discharge flow path from the fuel pump and injects the supplied alcohol mixed fuel. The apparatus is characterized in that an ultrasonic vibration means for promoting mixing of gasoline and alcohol by ultrasonic vibration is provided in the discharge flow path between the fuel pump and the injection valve.

Further, a float floating on the liquid level can be provided in the fuel tank, and the suction opening of the first fuel suction channel can be attached to the float.

Further, an alcohol concentration detection means for detecting the alcohol concentration in the alcohol mixed fuel can be provided in the discharge flow path from the fuel pump, located between the ultrasonic vibration means and the injection valve.

[Effect]

With this configuration, even if alcohol and gasoline are flowing in an uncertain mixed state in the discharge flow path,
By the external force of ultrasonic vibration by ultrasonic vibration means,
The bond between alcohol and water is broken. As a result, gasoline and water-free alcohol are mixed again, and the uniformly mixed alcohol-mixed gasoline is supplied to the injection valve.

Furthermore, by attaching the opening of the first fuel suction channel to the float, the mixture ratio of gasoline and alcohol can be maintained constant even if the liquid level changes.

Furthermore, since the alcohol detection means is provided downstream of the ultrasonic oscillation means, the detection accuracy of alcohol concentration can be improved.

〔Example〕

Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS. 1 and 2.

In Fig. 1, reference numeral 1 indicates a fuel tank mounted on a car.Although alcohol-mixed gasoline is supplied to the fuel tank 1, in Fig. 1, gasoline G is present in the upper layer, and alcohol A is present in the lower layer. The figure shows a state where the layer is separated into two layers.

A float 2 is provided in the fuel tank 1 and has a specific gravity lower than that of gasoline G, and the float 2 floats on the liquid surface of the gasonon G. Reference numeral 3 denotes a bellows tube disposed inside the fuel tank 1. The upper end of the bellows tube 3 is attached to the lid of the fuel tank 1 via a joint 4, and the lower end serves as a suction opening 3A and is attached to the float 2. and the suction opening 3
A is provided with a filter 5. 6 has one end as joint 4
The other end of the suction pipe is connected to a merging suction pipe 15 which will be described later, and a throttle valve 7 is provided in the middle of the suction pipe 6 to keep the mixing ratio constant as in the prior art. In this embodiment, the bellows tube 3. Joint 4. Suction pipe 6
The first fuel suction flow path 8 is constituted by the above.

On the other hand, 9 is a fixed suction pipe inserted from the lid to the bottom of the fuel tank 1, and the upper end of the fixed suction pipe 9 is connected to the joint 1.
0 to the lid of the fuel tank 1, the lower end thereof extends to the bottom to form a suction opening 9A, and a filter 11 is provided in the suction opening 9A. A suction pipe 12 has one end connected to the joint 10 and the other end connected to the merging suction pipe 15. A throttle valve 13 is provided in the middle of the suction pipe 12 to keep the mixing ratio constant.

In this embodiment, the fixed suction pipe nine-layer joint 10, the suction pipe 12, etc. constitute the second two fuel suction flow paths 14.

15 is the first. A merging suction pipe 16 is provided at the other end of the suction pipes 6 and 12 in order to merge the fuel sucked in from the second fuel suction flow path 8°14.
a fuel pump connected to the fuel pump 1;
6 is gasoline G sucked in from the first fuel suction channel 8 and alcohol A sucked in from the second fuel suction channel 14.
This system mixes and stirs the fuel and discharges it at a predetermined fuel pressure.

17 is a discharge pipe whose one end is connected to the discharge side of the fuel pump 16 and the other end is connected to a pressure regulator 29, which will be described later.
A fuel filter 18 is disposed in the middle of the discharge pipe 17. Ultrasonic transducer 19. Alcohol sensor 27, which will be described later. The injection valves 28 are provided in this order.

Here, the ultrasonic transducer 19 is provided in the enlarged diameter portion 17A that constitutes a part of the discharge pipe 17, and the ultrasonic transducer 19 is provided with washers 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 30 . . . . ring-shaped piezoelectric elements 21, 21 . ..., a horn 24 and a balancer 25 which sandwich each piezoelectric element 21 from both sides in the axial direction via bolts 22, nuts 23, etc., and a metal plate or the like provided at the tip of the horn 24 in a disk shape. It consists of a formed diaphragm 26.

Here, when a high frequency voltage is applied from the outside, each piezoelectric element 21 of the ultrasonic vibrator 19 generates ultrasonic vibration in the axial direction (vertical direction), and this vibration is amplified by the horn 24 and the diaphragm The vibrations are transmitted to the horn 26, and the balancer 25 balances the vibrations with respect to the horn 24. and,
The diaphragm 26 applies ultrasonic vibration to the gasoline G flowing in the enlarged diameter portion 17A and the alcohol A combined with water, and breaks the bond between water and alcohol to separate the alcohol A containing water. Gasoline G and pure alcohol A are uniformly mixed.

On the other hand, the alcohol sensor 27 is provided at the next stage of the ultrasonic vibrator 19 and detects the alcohol concentration in the alcohol-mixed gasoline, and this detection signal is sent to the injection amount calculation means (
(not shown), and the fuel injection amount is calculated along with the engine speed, intake air amount, etc. At this time, since the ultrasonic transducer 19 is provided before the alcohol sensor 27, highly accurate alcohol concentration detection is possible.

Furthermore, an injection valve 28 for injecting fuel into the engine, and a pressure regulator 29 for setting the fuel pressure injected by the injection valve 28 to a predetermined pressure are provided downstream of the alcohol sensor 27.
Excess oil when fuel pressure is controlled by the pressure regulator 29 is returned to the fuel tank 1 through a return pipe 30.

The present embodiment is constructed as described above, and its operation will be described next.

The alcohol-mixed gasoline in the fuel tank 1 is separated so that gasoline G is present in the upper layer and alcohol A containing moisture is present in the lower layer, as shown in the figure, and the float 2 is separated from the gasoline G.
It is assumed that the liquid is floating on the surface of the liquid.

In this state, when the fuel pump 16 is driven to rotate, the upper layer gasoline G is sucked from the filter 5 through the first fuel suction flow path 8, and the lower layer alcohol A is sucked from the filter 11 through the second fuel suction flow path 14. The fuel is sucked in through the merging suction pipe 15 and reaches the suction port of the fuel pump 16. At this time, the mixing ratio of gasoline G and alcohol A is maintained constant by the throttle valve 7.13.

The alcohol mixed gasoline mixed and stirred in the fuel pump 16 is discharged from the discharge pipe 17, and is discharged from the fuel filter 18. Ultrasonic transducer 19. Excess oil is injected into the engine from the injection valve 28 via the alcohol sensor 27 and whose fuel pressure is controlled by the pressure regulator 29, and is returned to the fuel tank 1.

However, in this embodiment, an ultrasonic vibrator 19 is provided between the fuel filter 18 and the alcohol sensor 27, and ultrasonic vibration is applied to the alcohol A combined with moisture, so that the alcohol A containing moisture is Breaking the bond between water and alcohol to promote separation, gasoline G and alcohol A
It is designed to mix evenly. As a result, unlike the prior art, the fuel pump 16 alone does not give the appearance of an upper level, but instead mixes gasoline G and pure alcohol A after bond breaking, resulting in an extremely good mixed gasoline. Become.

Further, as mentioned above, since the alcohol concentration is detected by the alcohol sensor 27 after being substantially and uniformly mixed by the ultrasonic vibrator 19, highly accurate detection is possible, and the fuel injection amount can be adjusted. Calculations can be performed accurately.

Moreover, as described above, it is possible to obtain a uniform alcohol-mixed gasoline, and since it is possible to detect the alcohol concentration with high precision, it is possible to obtain accurate starting performance and acceleration performance.

Furthermore, since the bellows tube 3 is used in the first fuel suction channel 8 and its suction opening 3A is attached to the float 2, so that the gasoline G is sucked from the liquid level, the liquid level in the fuel tank 1 is lowered. Even if the liquid level fluctuates upward or downward due to vibrations of the vehicle body, gasoline G can be sucked in by following these fluctuations.

In the embodiment, the fuel pump 16 is disposed outside the fuel tank 1, but the fuel pump 16 may be of an in-tank type and may be disposed inside the fuel pump 1.

Also, instead of one fuel pump 16, the first fuel pump 16 may be replaced with a first fuel pump 16. Separate fuel pumps may be provided in the second fuel suction channels 8 and 14, respectively, and the two fuel pumps may be joined together on the discharge side.

Furthermore, the ultrasonic vibration means is not limited to the configuration of the ultrasonic vibrator 19 of the embodiment, but can be made of piezoelectric material and have various shapes. , may be arranged in parallel.

[Effects of the Invention] The alcohol mixed fuel supply device according to the present invention is as described above in detail, and the alcohol-mixed fuel supply device according to the present invention applies ultrasonic waves to the mixture of gasoline and alcohol discharged from the fuel pump to break the bond between alcohol and water. Therefore, gasoline and alcohol can be supplied to the injection valve in a uniformly mixed state, and reliable fuel injection control is possible even during a cold start or a hot start.

[Brief explanation of drawings]

FIG. 1 is an overall configuration diagram showing an embodiment of the present invention, and FIG. 2 is a longitudinal sectional view of a main part of the ultrasonic transducer in FIG. 1. DESCRIPTION OF SYMBOLS 1... Fuel tank, 2... Float, 3... Bellows pipe, 4.10... Joint, 5, 11... Filter, 6
, 12... Suction pipe, 7.13... Throttle valve, 8...
- First fuel suction flow path, 9... fixed suction pipe, 14
... Second fuel suction flow path, 15... Merging suction pipe, 16... Fuel pump, 17... Discharge pipe, 19...
・Ultrasonic vibrator, 21... Piezoelectric element, 24... Horn, 25... Balancer, 26... Vibration plate, 27...
-Alcohol sensor, 28...Injection valve, 29...Pressure regulator, 30...Return pipe, G...Gasoline, A...Alcohol.

Claims (3)

[Claims] (1) a fuel tank that stores alcohol mixed fuel; a first fuel suction channel that opens on the upper side of the fuel tank;
a second fuel suction channel that opens to the lower side of the fuel tank; a fuel pump that discharges the fuel sucked in through the first and second fuel suction channels; and a discharge flow from the fuel pump. In an alcohol mixed fuel supply device that includes an injection valve that is installed in the middle of the road and injects the supplied alcohol mixed fuel, a part of the discharge flow path between the fuel pump and the injection valve is heated by ultrasonic vibration to inject gasoline and alcohol. An alcohol mixed fuel supply device characterized by being provided with ultrasonic vibration means for promoting mixing of alcohol. (2) The alcohol mixed fuel supply according to claim (1), wherein a float floating on the liquid surface is provided in the fuel tank, and the suction opening of the first fuel suction channel is attached to the float. Device. (3) The discharge flow path is provided with alcohol concentration detection means located between the ultrasonic vibration means and the injection valve to detect the alcohol concentration in the alcohol mixed fuel. alcohol mixed fuel supply system.