JPH0210284Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a fuel water separator for a diesel engine that can easily remove water from fuel.

(Prior Art) In general, in a diesel engine, each sliding part of an injection pump and an injection nozzle is precisely finished and is lubricated with fuel.
Therefore, when moisture is mixed into the fuel, the lubricity of these sliding parts decreases, causing premature wear and deterioration of the functions of the injection pump and injection nozzle. Furthermore, the ignitability and combustibility of the fuel are also reduced. In order to remove moisture in the fuel that causes such a decline in the function of the injection pump, a fuel water separator (sedimentor) is installed along with a fuel filter in the middle of the fuel pipe that connects the fuel tank and the injection pump. ing.

As such a fuel water separator, for example, the first
A fuel water separator as shown in the figure is known, and the configuration of this fuel water separator will be explained according to FIG. The separator 1 is connected to a fuel tank (not shown) on the upstream side. The downstream side of the water separator 1 is connected to a fuel filter 2, and the fuel filter 2 is connected to an injection pump (not shown). Therefore,
The fuel led from the fuel tank first flows into the water separator 1, and after the water in the fuel is separated by the water separator 1, it passes through the fuel filter 2 to remove dust and the like, and is sent to the injection pump. Ru.

The water separator 1 has a casing 3 in which a fuel layer and a water layer are separated, and a drain hole 4 is formed at the bottom of the casing 3 to discharge separated water to the outside. This drain hole 4 is connected to the plug 5
It can be opened and closed by Further, a priming pump 7 is provided at the upstream inlet section 6 of the water separator 1, and this priming pump 7 reciprocates within the cylinder formed by protruding diagonally from the inlet section 6. It is composed of a piston part and a threaded part screwed into the upper part of the cylinder.
The priming pump 7 pressurizes the fuel and bleeds air from the fuel system by loosening the threaded part and reciprocating the piston part, and also bleeds water from the water separator 1 as described below. be. That is, the water accumulated at the bottom of the casing 3 of the water separator 1 can be removed from the casing 3 by loosening the plug 5 and operating the priming pump 7.
The fuel inside is pressurized and discharged to the outside from the drain hole 4 (see "Nissan Service Bulletin" No. 418, p. 42, published by Nissan Motor Co., Ltd., April 1980).

However, in such a conventional water separator 1, the plug 5 is loosened and the priming pump 7 is turned off.
Since the water is discharged to the outside by activating the water separator 1, the priming pump 7 must be activated after loosening the plug 5 in order to drain water from the water separator 1. There was a problem that the operation was troublesome and required.

(Purpose of the invention) Therefore, the present invention opens above the drain hole,
The purpose is to facilitate water drainage by providing an air hole that can be sealed with a plug that seals the water drainage hole.

(Structure of the invention) The fuel water separator for a diesel engine according to the invention includes a casing in which a fuel layer and a water layer are separated, a first water drain hole located at the bottom of the casing, and a first drain hole located at the bottom of the casing. A first air hole is located at the bottom of the casing and is rotatably attached to the bottom of the casing.
a plug capable of sealing and opening a water drain hole and a first air hole; The plug has a second water drain hole that discharges water from the vent hole to the outside, and a second air hole that guides outside air to the first air hole when the first air hole is released. By providing an auxiliary hole that guides the discharged water from the first air hole to the second drain hole when the first and second air holes are opened, the inside of the casing can be drained by simply operating the plug. This is to drain water.

(Example) Hereinafter, the present invention will be explained based on the drawings.

2 to 4 are diagrams showing an embodiment of the present invention.

First, the structure will be explained. Reference numeral 11 indicates a casing of a water separator in which a fuel layer and a water layer are separated and formed, and a water draining unit 12 is attached to the bottom of the casing 11. Although the water separator is not shown, it is installed together with the fuel filter (or integrated therewith) in the fuel line between the fuel tank and the injection pump. The water drain unit 12 has a substantially cylindrical main body 13 screwed onto the casing 11, and a plug 14 which is rotatably attached to the main body 13 and can be screwed into the main body 13. Main body 1
3 is formed with a recess 15 that opens downward in FIG.
6 and a large diameter recess 17. Also, main body 1
3 has a first drain hole 18 whose upper end (indicates the upper part in FIG. 2; the lower end refers to the lower part; the same applies hereinafter) opens into the casing 11 and whose lower end opens into the small diameter recess 16; From that of the first drain hole 18
A first air hole 19 opens upward by the height of H ₁ (for example, set to H ₁ = 15 mm) and has a lower end opening into the large diameter recess 17, and a first air hole 19 whose upper end opens into the large diameter recess 17 and whose lower end opens into the large diameter recess 17. Opening to the outer peripheral surface of the main body 13, that is, to the outside,
A second air hole 20 is formed that guides outside air to the first air hole 19 when the first air hole 19 is opened.

Generally, if H ₁ ≧10 mm is set when air is sent into the water as shown in FIG. 21. That is, the water drain hole 22 and the air hole 23
Due to the head pressure difference at each upper end of the container 21, external air is efficiently sent into the container 21, whereby the water in the container 21 is easily discharged to the outside. On the other hand, when H ₁ <10 mm, the water and air passages are not completely differentiated, and water may also be drained from the air hole 23, for example, and water is discharged from the above-mentioned H ₁
Inferior to the state of ≧10mm. Therefore, when sending air into the water, it is sufficient to set H ₁ ≧10mm,
In this embodiment, H ₁ =15 mm is selected to provide a margin. Note that when using other liquids, this height H ₁ may be suitably determined by taking into account the difference in specific gravity with water.

Referring again to FIG. 2, the plug 14 has a small diameter portion 24 and a large diameter portion 25 that fit into the small diameter recess 16 and large diameter recess 17 of the main body 13, respectively.
A threaded portion 25a formed on the outer peripheral surface of the large diameter portion 25 is screwed into a threaded portion 17a formed in the large diameter recessed portion 17. An O-ring 26 is attached to the small diameter portion 24 of the plug 14.
However, O-rings 27 are attached to each of the large-diameter portions 25, and these O-rings 26, 27 are inserted between the recess 15 and the plug 14 when the plug is tightened (i.e., other than when draining water). The gap formed is sealed to maintain airtightness inside and outside the casing 11.
Furthermore, inside the plug 14, there is a
A second drain hole 28 is formed which extends in the vertical direction (in the figure) and whose lower end opens to the outside, and the upper end of this second drain hole 28 is formed into a needle shape when the plug 14 is tightened. It is closed by contacting the inner wall surface of the small diameter recess 16. Therefore, when the plug 14 is tightened, the first drain hole 18 is sealed by the plug 14. The second drain hole 28 is the same as the first drain hole 1.
8, and when the plug 14 is loosened during draining operation, it communicates with the first drain hole 18. These first and second drain holes 1
Reference numerals 8 and 28 serve as water passages that communicate the inside and outside of the casing 11 during the water draining operation and discharge the water inside the casing 11 to the outside. Furthermore, the plug 14 has the plug 1
4, that is, when the first and second air holes 19 and 20 are opened, the first air hole 19
An auxiliary hole 29 is formed to guide the water discharged from the main body to the second drain hole 28, and the upper end of this auxiliary hole 29 is connected to the upper end of the second air hole 20 formed in the main body when the plug 14 is tightened. Plug 1 so that it is in approximately the same position.
The large diameter portion 25 of No. 4 opens on the outer peripheral surface (that is, communicates with the large diameter recess 17), and the lower end is connected to the second portion below the upper end.
The drain hole 28 is opened. Therefore, the auxiliary hole 29 has a downward slope. This auxiliary hole 2
The inner diameter of the air hole 9 is set to be equal to or smaller than the inner diameter of the first air hole 19. When the plug 14 is tightened, communication between the first and second air holes 19 and 20 formed in the main body 13 is cut off by an O-ring 27 attached to the large diameter portion 25.
When loosening 4, the inside and outside of the casing 11 are communicated, forming an air passageway that guides outside air into the casing 11. It is attached to the small diameter portion 24. Even if this air passage is formed when the plug 14 is operated, the O-ring 26 is set at a position where it can block communication with the water passage and separate the passages from each other.

Next, the effect will be explained.

When a fuel layer and a water layer are separated and formed in the casing 11 of the water separator due to the difference in specific gravity, the plug 14
When loosened, the upper end of the second drain hole 28 opens and the drain holes 18, 28 open as shown in FIG.
Then, the airtightness provided by the O-ring 27 is released, and the first and second air holes 19 and 20 communicate with each other. Therefore, the inside of the casing 11 has these drain holes 18, 28 and the first and second holes.
It communicates with the outside through air holes 19 and 20. At this time, since the first air hole 19 opens upward by H ₁ = 15 mm compared to the first drain hole 18 in the casing 11, it is separated into the bottom part of the casing 11 based on the above-mentioned principle. Water is discharged to the outside through the drain holes 18 and 28, and outside air flows into the interior through the first and second air holes 19 and 20. Thereafter, water continues to be discharged by a so-called siphon effect. When the plug 14 is loosened when the water in the casing 11 has been drained, the second
Since the upper end of the drain hole 28 contacts the inner wall surface of the small-diameter recess 16 and is closed, communication between the drain holes 18 and 28 is cut off, and the O-ring 27
And communication between the second air holes 19 and 20 is cut off. As a result, communication between the inside and outside of the casing 11 is cut off, and the casing 11 is kept airtight. In this way, in this embodiment, there is no need to operate the priming pump to discharge water from the water separator, and water can be efficiently discharged by simply loosening the plug 14.

Moreover, the first and second air holes 19, 20 and the first,
Since the drain holes 18 and 28 of No. 2 are completely separated with only a slight communication via the auxiliary hole 29, it is possible to exchange air and water (inflow of air into the casing 11 and out of the casing 11). The water discharged from the first drainage hole 18 is mixed with the air and the water discharged from the first drainage hole 18 is mixed with air.
The water will not be discharged from the drain hole 28. Therefore, water can be discharged from the casing 11 extremely efficiently.

Next, the function of the auxiliary hole 29 will be explained.

Before the plug 14 is loosened, water (or fuel) in the casing 11 remains in the air hole 19 as well. Therefore, as shown in FIG. 4, when the plug 14 is loosened and the airtightness provided by the O-ring 27 is released, only the water that had accumulated in the first air hole 19 will flow out of the first air hole 19. then move downward.
At this time, the water drain holes 18 and 28 are already communicating with each other, and the water in the casing 11 is discharged to the outside through the water drain holes 18 and 28 at the same time as the airtightness provided by the O ring 27 is released. Also,
The inner diameter of the second drain hole 28 is the same as that of the first drain hole 18.
Since the second drain hole 28 is slightly larger than that of the second drain hole 28, the second drain hole 28 is in a slightly negative pressure state. Therefore, the water that has moved downward from the first air hole 19 as described above passes through the auxiliary hole 29 and is in a negative pressure state. The water is sucked into the second drain hole 28 and discharged to the outside.
The air does not flow out through the second air hole 20 to the outer circumferential surface of the main body 13 or the outer circumferential surface of the plug 14 . Further, even when the water in the casing 11 is completely drained and the plug 14 is inserted into the tightening recess 15, the water from the first air hole 19 has already been drained as described above, and the outer peripheral surface of the plug 14 It will not leak out. As a result, water (or fuel) from the first air hole 19
The plug 14 can be operated without getting the hands dirty by discharging the plug. In addition, the main body 13 and the plug 14
Since water (or fuel) does not flow out onto the outer peripheral surfaces of the fuel tank, it is possible to prevent dust from adhering to these outer peripheral surfaces and reduce dirt.

In addition, since the auxiliary hole 29 receives negative pressure from the second drain hole 28, it can also be formed horizontally.

In addition, in the above embodiment, H ₁ is set to 15 mm, but if, for example, a vinyl pipe or the like is connected to the plug 14 to guide the discharged water to the bottom of the engine,
It has been practically confirmed that the siphon effect becomes large and there is no significant difference in the discharge effect even if H ₁ is set to 10 mm or less or H ₁ ≈0 mm.

Although the above embodiment is an example in which the water drainage unit is applied to the bottom of the fuel water separator, it is understood that this water drainage unit can also be applied to the bottom of a fuel filter that is integrated with the fuel water separator. Of course.

In addition, in diesel engines, air contamination in the fuel can cause the engine to stop, so it should be avoided as much as possible. The function is to gradually release air mixed into the fuel during the engine operation stage, and air mixed into the fuel does not interfere with engine operation.

(Effects) According to the present invention, water can be drained simply by loosening the plug, and water can be drained easily. In addition, the first and second air holes and the first and second water drainage holes are completely separate passages, only communicating through the auxiliary hole, so air and water can be exchanged easily. This can be carried out smoothly, and the water discharged from the first drain hole is not mixed with air and discharged from the second drain hole, and water can be discharged extremely efficiently. Furthermore, since an auxiliary hole is formed in the plug so that the first air hole and the second drain hole communicate with each other, water can be drained without getting your hands dirty with discharged water or fuel, and the outer periphery of the plug etc. It is possible to prevent dust from adhering to the surface and reduce dirt.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway side view showing a conventional fuel water separator, Figs. 2 to 4 are views showing an embodiment of the present invention, Fig. 2 is a partial sectional view thereof, and Fig. 3 is its A schematic diagram for explaining the principle of operation, and FIG. 4 is a partial sectional view showing the water draining operation. 11...Casing, 14...Plug, 18...
...First water drain hole, 19...First air hole, 20
...Second air hole, 28...Second water drain hole, 2
9...Auxiliary hole.

Claims (1)

[Scope of utility model registration request] A casing in which a fuel layer and a water layer are formed separately, a first water drain hole located at the bottom of the casing, and a first air hole located at the bottom of the casing and opened above the first water drain hole. a hole, a plug rotatably attached to the bottom of the casing and capable of sealing and opening the first water drain hole and the first air hole; and a plug extending in the axial direction inside the plug. a second drain hole that drains water from the first drain hole to the outside when the first drain hole is opened; and a second drain hole that drains outside air to the outside when the first air hole is opened. a second air hole that leads to the air hole, and an auxiliary hole that is formed in the plug and that leads the discharged water from the first air hole to the second drain hole when the first and second air holes are opened; A diesel engine fuel water separator characterized by comprising: