JPH0515570Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a fuel filter with an air bleed mechanism that is installed in the middle of a fuel passage that supplies fuel to engines such as tractors and cultivators, and general-purpose engines.

(Conventional technology) The prior art will be explained with reference to FIG.

A fuel overflow element 39 is attached to the lower part of the main body 33 of the fuel filter, and the element 3
A cup 40 is fixed to the main body 33 with a ring nut 42. Also, the cup 40
The inside is divided by an element 39, and a front chamber 47 is defined outside the element 39, and a rear chamber 48 is defined inside the element 39.

An air reservoir 50 for bleeding air is formed in an upper portion of the front chamber 47, and a valve chamber 52 is formed above the air reservoir 50 and communicates with the air reservoir 50 through an air passage 51. The valve chamber 52 is connected to the fuel passage 4.
9 communicates with the rear chamber 48 and also communicates with the fuel outlet passage 53 .

A valve seat 55 is formed in the valve chamber 52 , and a valve body 56 equipped with an O-ring 57 that can come into close contact with the valve seat 55 is disposed within the valve chamber 52 .
is pressed against the valve seat 55 by the biasing force of a spring 60 interposed between a push button 61 mounted outside the main body 33 and a washer 59 which is a presser for the O-ring 58 mounted in the opening of the main body 33. The O-ring 57 and the valve seat 55 are in close contact with each other, and the air passage 51 and the fuel outlet passage 53 are cut off.

The conventional fuel filter having the above configuration is located above the fuel tank and is provided between the fuel filter and the injection pump, which sucks fuel from the fuel outlet passage 53 of the fuel filter and supplies it to the injection pump. supply.

Fuel sucked from the fuel tank flows into the fuel inlet passage 45 and enters the front chamber 47 and element 3.
9. The fuel is led to the fuel outlet passage 53 via the post-heating chamber 48.

In this case, the air in the post-air chamber 48 is sucked into the fuel pump from the fuel outlet passage 53 together with the fuel, but the O-ring 57 attached to the valve body 56 is in close contact with the valve seat 55 of the valve chamber 52, so that no air accumulates. Since the air passage 51 communicating with the section 50 is in a "closed" state, the air in the front chamber 47 remains in the air reservoir section 50.

On the other hand, when removing the air accumulated in the air reservoir 50, by pressing the pushbutton 61 attached to the valve body 56, the valve body 56 moves against the biasing force of the spring 60, and the valve body 56 is moved. O attached
The ring 57 is separated from the valve seat 55 of the valve chamber 52,
Air passage 51 and fuel outlet passage 53 communicate (“open”)
state), and the air accumulated in the air reservoir 50 is sucked into the fuel pump from the fuel outlet passage 53.

(Problems to be Solved by the Invention) In the conventional technology having the above configuration and operation, when air is removed, after the air accumulated in the air reservoir 50 is sucked into the fuel pump from the fuel outlet passage 53, Since excess fuel in the front chamber 47 is sucked together with air into the fuel pump, it has an adverse effect on the fuel pump or injection pump.

Therefore, for example, by arranging a material having the same overperformance as the element 39 in the air reservoir 50, the fuel in the overflow chamber 47 is passed through the material and then sucked into the fuel pump from the fuel outlet passage 53. However, when air is removed, due to the difference in pressure loss between the pre-exhaust chamber 47 and the after-exhaust chamber 48, the air and fuel in the after-exhaust chamber 48 are sucked into the fuel pump from the fuel outlet passage 53. On the other hand, since the air and fuel in the front chamber 47 are not sucked by the fuel pump, the air accumulated in the air reservoir 50 cannot be removed, and the provision of the air removal mechanism becomes meaningless.

(Means for solving the problem) The present invention was devised to solve the above problem, and uses a fuel pump located above the fuel tank and provided between the injection pump and the fuel tank. An air reservoir is provided above the front chamber and a fuel passage is provided above the rear chamber, and the air reservoir and the fuel passage are communicated with the valve chamber. In a fuel filter with an air bleed mechanism, the valve chamber is connected to the fuel outlet passage, and the first valve seat is placed on the air reservoir side and the first valve seat is placed on the fuel passage side across the fuel outlet passage. A second valve seat is formed, and a first valve biased by a spring is disposed in the valve chamber on the first valve seat side so as to be always kept in close contact with the first valve seat, and the first valve on the second valve seat side is A second valve is disposed in the chamber and is urged by a spring so as to be always kept away from the second valve seat, and is connected to a pushbutton.When the pushbutton is pressed, the first valve is brought into an "open" state. Further, a protrusion is formed on the end face of the first valve or the second valve so that the second valve is in a "closed" state, and a material is attached to the air reservoir.

(Function) In the present invention having the above configuration, normally the first valve is in the "closed" state and the second valve is in the "open" state, so the front chamber does not communicate with the fuel outlet passage, and only the rear chamber is in communication with the fuel outlet passage. Communicates with the fuel outlet passage. Therefore, the air and fuel inside the chamber are sucked into the fuel pump from the fuel outlet passage, but
The air in the front chamber remains in the air reservoir.

When the pushbutton is pressed in this state, the end face of the second valve comes into contact with the protrusion formed on the end face of the first valve (or the protrusion formed on the end face of the second valve comes into contact with the end face of the first valve). Then, the first valve is pressed by the second valve and moves away from the first valve seat to open.
state. On the other hand, the second valve is in close contact with the second valve seat and is in the "closed" state. Therefore, only the front chamber communicates with the fuel outlet passage, and the air accumulated in the air reservoir is sucked into the fuel pump from the fuel outlet passage.
Air is removed from the front chamber. In this case, the fuel in the front chamber is passed through a material attached to the air reservoir, and then sucked into the fuel pump from the fuel outlet passage.

Thereafter, when the push button is released (after the air in the front chamber has been bleed), the second valve is separated from the second valve seat by the biasing force of the spring, and becomes in the "open" state. Further, the first valve is brought into close contact with the first valve seat by the biasing force of the spring, and is in the "closed" state, returning to the normal operating state.

(Example) An example of the present invention will be described below with reference to FIG.

A fuel overflow element 4 is attached to the lower part of the main body 1, and a cup 5 covering the element 4 is fixed to the main body 1 by a ring nut 7.
The inside of the cup 5 is divided by an element 4, with a front chamber 9 and a rear chamber 10 defined on the outside and inside of the element 4, respectively.

An air reservoir 1 is located in an upper part of the front chamber 9.
Further, a valve chamber 14 is formed above the air reservoir 12 and communicated with the air reservoir 12 through an air passage 13. Further, the valve chamber 14 is connected to the exhaust chamber 10 by the fuel passage 11.
A fuel outlet passage 1 is connected between the opening of the air passage 13 and the opening of the fuel passage 11.
5 is passing through.

A first valve seat 17 is provided between the opening of the fuel outlet passage 15 and the air passage 13 in the valve chamber 14, and a first valve seat 17 is provided between the opening of the fuel outlet passage 15 and the opening of the air passage 13.
A second valve seat 24 is formed between the first valve seat 17 and the first valve seat 17, and a second valve seat 24 is formed between the first valve seat 17 and the first valve seat 17. Valve 18 is placed. The first valve 18 is always pressed against the first valve seat 17 by a spring 20 interposed between the first valve 18 and a blind plug 21 screwed onto the main body 1,
The ring 19 and the first valve seat 17 are in close contact to maintain airtightness, and a rod-shaped projection 23 is formed on the end surface 22 of the first valve 18.

In addition, a second valve 25 equipped with an O-ring 26 that can be brought into close contact with the second valve seat 24 is disposed in the valve chamber 14 on the other second valve seat 24 side.
The bearing 27 and the second valve 25 are screwed onto the main body 1.
It is always kept away from the second valve seat 24 by a spring 28 interposed between the push button 29 and the push button 29 screwed into the valve seat 24.

In addition, in the air reservoir 12 of the front chamber 9, a material 31 having the same performance as the element 4 attached to the main body 1 is fixed to the main body 1 in an airtight manner by a bush 32.

In one embodiment having the above configuration, since the first valve 18 is normally in the "closed" state and the second valve 25 is in the "open" state, the air and fuel in the aftertreatment chamber 10 are supplied from the fuel outlet passage 15 to the fuel pump. However, the air in the front chamber 9 remains trapped in the air reservoir 12.

When the pushbutton 29 is pressed, the end surface 30 of the second valve 25 comes into contact with the protrusion 23 of the first valve 18, and the first valve 18 is pushed away from the first valve seat 17 by the second valve 25 and "opened." ” state, and the second valve 25 comes into close contact with the second valve seat 24 and becomes a “closed” state. Therefore, the air reservoir 12
The air accumulated in the front chamber 9 is sucked into the fuel pump through the fuel outlet passage 15, and the air in the front chamber 9 is vented. In addition, the fuel in the front chamber 9 is
After passing through the material 31 attached to the fuel pump 2, the fuel is sucked into the fuel pump through the fuel outlet passage 15.

When the push button 29 is then released, the first valve 18 returns to the "closed" state and the second valve 25 returns to the "open" state due to the urging force of the springs 20 and 28.

(Effects) As described above, the present invention attaches a material to the air reservoir, and when air is removed, the after-exhaust chamber is "closed" and only the before-exhaust chamber is "open". (i) Unexcess fuel is removed. There is no suction into the fuel pump.

(ii) The air in the postpartum chamber can be vented smoothly.

This is a useful idea that solves all the problems of the past all at once.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing one embodiment of the present invention;
The figure is a sectional view of the prior art. 9...Extreme anterior chamber, 10...Extreme posterior chamber, 11...
Fuel passage, 12...Air reservoir, 14...Valve chamber, 15...Fuel outlet passage, 17...First valve seat, 18...First valve, 24...Second valve seat, 2
5...Second valve, 29...Push button, 31...
...Material.

Claims (1)

[Claim for Utility Model Registration] Fuel is sucked by a fuel pump located above the fuel tank and installed between the fuel tank and the injection pump, with an air reservoir above the front chamber and an air pocket above the rear chamber. A fuel filter with an air bleed mechanism is provided with a fuel passage, the air reservoir and the fuel passage communicate with a valve chamber, and the air is bleed by pressing a pushbutton, the fuel filter having a fuel outlet passage in the valve chamber. At the same time, a first valve seat is formed on the air reservoir side and a second valve seat is formed on the fuel passage side across the fuel outlet passage, and the first valve seat is always formed in the valve chamber on the first valve seat side. A first valve biased by a spring is disposed so as to be held in close contact with the seat, and a valve chamber on the second valve seat side is biased by a spring so as to be always kept separated from the second valve seat. and a second valve connected to the pushbutton, and a protrusion on the end face of the first valve or the second valve so that when the pushbutton is pressed, the first valve is in the "open" state and the second valve is in the "closed" state. 1. A fuel filter with an air bleed mechanism, characterized in that a material is attached to the air reservoir.