JPH08225022A - Liquid cutoff valve - Google Patents

Abstract

PURPOSE: To make the valve of a disk remobale easily from a valve seat, by holding a valve disk tiltable at the upper side of a float by plural claws with different lengths, in a liquid cutoff valve to cut off the flowing out of a liquid by closing the valve, when a fuel tank or the like is inclined or overturned in the vehicle running condition. CONSTITUTION: When a liquid such as a fuel is reduced, a float 6 is going to sink by its empty weight, and a valve disk 32 stuck to a valve seat 18 is going to be lowered by removing it by plural claws 34 and 36. In this case, since the lengths of the claws are different, only the shorter claw 36 is hooked to the valve disk 32, and the lowering force is to be given. The valve 22 of the valve disk 32 is pulled by the short claw 36 and inclined when it is not separated rapidly from the valve seat 18 by cutting the contact with the valve seat, and the upper surface of the disk 32 is abutted to a projection 42. By making the abutting part as a fulcrum, the tensile force of the float 6 is operated as a moment. Consequently, the valve 22 is removed from the valve seat 18 easily so as to be opened.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used, for example, in a fuel tank of an automobile or the like, and in a normal state, the pressure generated inside the fuel tank or the like (because the fuel vaporizes if the liquid to be stored is fuel). The vapor pressure becomes the internal pressure.), And is closed when the fuel tank, etc. is shaken, tilted, or falls due to running of a car, etc., to shut off the outflow of the stored liquid. Regarding

In particular, the present invention relates to a liquid shutoff valve which prevents a valve portion provided on the float from being separated from a valve seat, of a type in which a vent pipe is opened and closed by using a float.

[0003]

[Prior art]

(First Conventional Example) A conventional liquid cutoff valve having a float is initially shown in FIGS. 3 (a) and 3 (b). To explain this, 102 is a hollow valve body, 104 is a cap incorporated in the lower part of the valve body 102, and 106 is the valve body 102 and the cap 10.
4 is a float that constitutes a valve element that is vertically held in an internal space created by 4. 108 is a spring,
The float 10 has a spring force weaker than the weight of the float 106.
6 is biased upward.

A flange 110 for fixing is provided on the outer upper portion of the valve body 102, and the flange 110 has a plurality of screw holes 112. Covering the flange 110 is a fixing cover 114, and below the flange 110 is a packing 116. For example, a liquid cutoff valve is provided in a hole provided in an upper portion of a fuel tank or the like. The cover 114, the flange 110, and the packing 116 are fixed to the upper portion of the fuel tank and the like with screws, and fixed so that liquid such as fuel inside does not leak.

A valve seat 118 is provided in the center of the upper surface of the inside of the valve body 102, and the inside of the valve body 102 is communicated with the outside through a ventilation conduit 120 which is a passage. In addition, there is a protruding valve portion 122 at the center of the upper surface of the float 106, which constitutes a valve together with the valve seat 118, and the vertical movement of the float 106 opens and closes the valve. A plurality of vertical grooves 1 is provided on the side surface of the float 106.
24, which connects the space above and below the float 106, allowing liquids and vapors to freely flow in and out.

A hole 126 is formed in the center of the cap 104.
Therefore, the inside of the fuel tank or the like is communicated with the inside of the valve body 102.

The liquid shutoff valve of the type having a float of the first conventional example having the above structure has the float 106 due to the buoyancy of the liquid such as fuel contained in the fuel tank or the like.
Even if the liquid level drops after the valve is closed by the valve portion 222 of the float 106, due to the pressure difference between the inside and outside of the fuel tank,
The valve portion 122 of the above may not be separated while being fixed to the valve seat 118.

(Second Conventional Example) Therefore, in order to improve the liquid shutoff valve having the first conventional structure shown in FIG. 3, those shown in FIGS. 4 to 7 have been proposed. In the structure of the second conventional example, the valve portion on the upper surface of the float is separated from the float, and the valve disc 232 abutting on the valve seat 218 movable relative to the float 206 provided on the upper surface of the valve body 202 is provided. , 2 different lengths on top of float 206
The claws 234 and 236 of the book are held so as to be tiltable.

The structure of the second conventional example will be described in more detail. Reference numeral 202 is a hollow valve body, 204 is a cap incorporated in the lower portion of the valve body 202, and 20 is a cap.
Reference numeral 6 is a float that constitutes a valve element that is vertically movably held in an internal space created by the valve body 2 and the cap 4.

A valve disc 232 is mounted on the upper surface of the float 206, and two hook-shaped pawls 234 and 236 provided on the upper surface of the float 206 and having different lengths.
However, the valve disc 232 is held to be tiltable to some extent. And when the float 206 rises,
Lift the valve disc 232 in the correct position without tilting. However, when the float 206 descends, the valve disc 23 is pulled by the two hooks 234, 236 having different lengths so as to pull the valve disc 23.
A slight inclination to 2 is allowed.

Reference numeral 208 denotes a spring, which urges the float 206 upward with a spring force weaker than the weight of the float 206.

A flange 210 for fixing is provided on the upper outer side of the valve body 202, and the flange 210 has a plurality of screw holes 212. Covering the flange 210 is a fixing cover 214, and below the flange 210 is a packing 216. For example, a liquid cutoff valve is provided in a hole provided in the upper portion of a fuel tank or the like. The cover 214, the flange 210, and the packing 216 are fixed to the upper portion of the fuel tank and the like with screws so that the liquid such as the fuel inside does not leak.

A dish-shaped valve seat 218 is provided in the center of the upper surface of the inside of the valve body 202, and the inside of the valve body 202 is communicated with the outside through a valve hole 219 and a ventilation conduit 220 which is a passage. Also, the valve disc 2
There is a protruding valve portion 222 at the center of the upper surface of 32, which constitutes a valve together with the valve seat 218, and the valve is opened and closed by the vertical movement of the float 206.

A plurality of vertical grooves 2 are provided on the side surface of the float 206.
24, which connects the space above and below the float 206 so that liquid and gas can freely flow in and out. Also,
There is a hole 226 in the center of the cap 204, which connects the inside of the fuel tank and the like with the inside of the valve body 202.

FIG. 4 shows an open state of the liquid cutoff valve according to the second conventional example, FIG. 5 shows a liquid level rise and closed state, and FIG. 6 shows a reopened valve state.

The purpose of the structure of the second conventional example is that when the liquid level goes down and the float 206 tries to go down by its own weight, as shown in FIG. 6, it is hooked on the valve disc 232 by only the shorter pawl 236. By applying a moment with the opposite side of the short pawl 236 as a fulcrum, the valve portion 222 of the valve disc 232 is pulled away from the valve seat 218 by a force that is several times larger than the force applied by the pawl.

[0017]

However, as a result, in the structure of the second conventional example, the force applied to the valve is only the weight of the float 206 (downward), and the peeling force is still insufficient. The reason for this is that the valve disc 232 tilts due to the moment, but the valve disc 232 does not try to separate easily, and as a result, the short pawl 236 and the long pawl 234 end up.
Means that the valve disk 232 is pulled, and only the weight of the float 206 is pulled, not the moment, and the peeling force becomes insufficient.

As a countermeasure against this, as shown in FIG. 7, if a slit-like notch 300 is formed in the valve portion 222 in a direction perpendicular to the direction in which the claw is present, it is easy to open the valve, but the dimension ensures a reliable seal. Is difficult to do.

The present invention has been made to solve the above-mentioned problems of the prior art, and the purpose thereof is to:
The purpose of the present invention is to provide a liquid cutoff valve that allows the valve portion of the valve disc to be easily separated from the valve seat.

[0020]

In order to achieve the above object, according to the present invention, an internal hollow valve body is provided at the upper part of a tank for storing a liquid, and the valve body is inserted into the hollow interior of the valve body. A valve body that moves up and down together with the liquid level of the liquid in the tank that flows into the valve body, a passage that communicates with the inside and outside of the tank that opens at the top of the valve body, and a valve seat that is provided at the opening of the passage. And the valve body has a float and a valve disc having a valve portion, which is held on the upper part of the float so as to be relatively movable with respect to the float, and has a liquid level of a liquid flowing into the valve body. In a liquid cutoff valve in which a valve portion of a valve disc forming the valve body comes into contact with and separates from the valve seat according to a height to open and close the passage, a plurality of the valve discs are provided above the float. With the pawl held so as to be tiltable, one pawl of the plurality of pawls is made shorter than the other pawl, and the pawl is opened from the upper portion of the valve body on the side opposite to the center of the valve seat from the short pawl. It is characterized in that a protrusion is provided on which the upper surface of the valve disc abuts when the valve is opened.

[0021]

In the liquid cutoff valve having the above structure, since the short pawl with respect to the center of the valve seat is provided with the protruding portion from the upper portion of the valve body, the longer pawl is provided when the valve disc is tilted. Before the is caught on the valve disc, the protrusion from the upper part of the valve body and the upper face of the valve disc collide, and this becomes the fulcrum of the moment generated when pulling the valve disc with the short pawl, and the moment works effectively until the end, Helps pull the valve portion of the valve disc away from the valve seat.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the illustrated embodiments. 1 and 2 showing a liquid cutoff valve according to an embodiment of the present invention, 2 is a hollow valve body, 4 is a cap incorporated in the lower portion of the valve body 2, and 6 is a valve body 2 and a cap 4. It is a float that constitutes a valve body that is vertically movably held in an internal space to be created.

A valve disc 32 having a valve portion 22 is mounted on the float 6 so as to be movable relative to the float 6, and a plurality of hook-shaped pawls 34, 36 provided on the upper surface of the float 6 are provided. , A plurality of elongated holes 40, 40, 40 provided in the valve disc 32 (FIGS. 2C and 2D)
(Refer to FIG. 3), the valve disc 32 is held so as to be tiltable to some extent. And one of the multiple pawls
Only the pawl 36, which is an individual, has a shorter arm length. Therefore, when the float 6 rises, the valve disc 32 is lifted in a correct posture without being tilted.
However, when the float 6 descends, the valve disc 32 is first pulled by the short pawl 36.

Reference numeral 8 denotes a spring, which urges the float 6 upward with a spring force weaker than the weight of the float 6.

A flange 10 for fixing is provided on the upper outer side of the valve body 2, and the flange 10 has a plurality of screw holes. Covering the flange 10 is a fixing cover 14, and below the flange 10 is the packing 1.
6, the liquid cutoff valve is inserted and incorporated into the hole provided in the upper portion of the fuel tank or the like from above, and the cover 14, the flange 10 and the packing 16 are screwed to the upper portion of the fuel tank or the like. It is fixed so that liquid such as fuel inside does not leak.

At the center of the upper surface of the valve body 2, there is a dish-shaped valve seat 18, a valve hole 19, a gas chamber 17,
The inside of the valve body 2 is communicated with the outside through a ventilation pipe 20 and a nipple 21 that form a passage. The opening angle α of the dish-shaped tapered surface of the valve seat 18 forms a large angle of 90 degrees or more (see FIGS. 2A and 2B).

Further, the valve disc 32 has a protruding valve portion 22 at the center of the upper surface thereof, which constitutes a valve together with the valve seat 18, and the valve 6 is opened and closed by the vertical movement of the float 6. The surface of the valve portion 22 is spherical, and is fitted to the surface of the tapered valve seat 18 even if there is some inclination. In addition to that, since the opening angle α of the tapered surface of the valve seat 18 is 90 degrees or more, the engagement between the valve seat 18 and the valve portion 22 is shallow,
The valve portion 22 has the property of easily slipping and tilting even when it is adsorbed to the valve seat 18.

Reference numeral 42 is one of the present invention, and is a projecting portion provided on the inner upper surface of the valve body 2, and is located at a position opposite to the short pawl 36 with respect to the center of the valve seat 18. It is in. Further, the height of the protrusion 42 is such that when the float 6 rises and the valve disc 32 is lifted in a posture in which it is not tilted, the protrusion 42 still has the valve disc 32.
When the valve disc 32 tilts while being attracted by the float 6 descending and the valve disc 32 is first pulled by the short pawl 36 without contacting the upper surface of the valve disc 32, the long pawl 34 is not caught by the valve disc 32. In addition, the height is such that the protrusion 42 contacts the upper surface of the valve disc 32.

When the projection 42 is provided in this manner, the float 6 rotates and the long pawl 34 moves to the position of the projection 42, and when the float 6 rises in this state, the long pawl 3 is provided.
4 will be hit.

Therefore, it is necessary to regulate the valve body 2 and the float 6 in the rotating direction, and the rotation stopping means 50 is provided as shown in FIG. 1 (b). This rotation stopping means 50
Is a concave portion 51 provided on the side wall of the float 6 in two equal parts,
51 and projections 52, 5 provided on the side surfaces of the inner space of the valve body 2 that engage with the recesses 51, 51, respectively.
It consists of two. Incidentally, the rotation stopping means 50 is not limited to this, and in essence, the rotation stopping means 50 may be configured to prevent the float 6 from rotating.

In addition to the protrusions 52, a plurality of vertical ribs 24 are provided on the side surface of the inner space of the valve body 2 so as to hold the float 6 so that the float 6 can be moved up and down, and a space between the float 6 and the side surface thereof. To make the space above and below the float 6 communicate with each other, allowing liquid and gas to freely flow in and out. In addition, the cap 4 has a plurality of holes 26 to connect the inside of the fuel tank and the like to the inside of the valve body 2.

Further, 44 and 46 are parts incorporated in the upper part of the valve body 2 in order to make a passage including the gas chamber 17 for communicating the inside of the valve body 2 with the outside, and usually the nipple 21. It is also integrated with the valve body 2. 44 is the valve seat 18 and the protrusion 4
2 is a valve seat plate having 2, 46 is a gas chamber cap.

The embodiment of the liquid cutoff valve according to the present invention constructed as above operates as follows.

First, in a normal state in which the liquid level in the tank is lowered, the float 6 is lowered because no buoyancy is applied, and the valve is open (see FIG. 1).

In this state, when the liquid is injected into the tank by refueling or the like, the volume of the gas in the tank is narrowed by the rise of the liquid level, the pressure in the tank rises, and the hole 26 of the cap 4 and the liquid are blocked from the inside of the tank. Inside the valve and through the valve,
It escapes to the outside through the gas chamber 17, the ventilation pipe line 20, and the nipple 21.

When the state of fullness is approached, the liquid also enters from the inside of the tank into the inside of the liquid cutoff valve, and lifts the float 6 by buoyancy. At this time, the float 6 is attached to the valve disc 3
2 with the correct posture, and the valve part 22 with the valve seat 1
Correctly abut with No. 8, and close the valve.

When the liquid such as fuel is consumed and the liquid is reduced from the full tank, the liquid surface is lowered and the buoyancy is lost. Then, the float 6 tries to lower by its own weight, and the valve disc 32 attached to the valve seat 18 due to the pressure difference of the gas pressure applied to the upper and lower surfaces of the float 6,
Attempts to pull them apart and lower them with a plurality of hook-shaped pawls 34, 36.

In this case, since the lengths of the pawls are different, only the short pawl 36 is caught by the valve disc 32 and exerts a pulling-down force. The valve portion 22 of the valve disc 32 may be released immediately after breaking contact with the valve seat 18, but if not, the valve portion 22 is pulled by the short pawl 36 and tilted, and the upper surface of the valve disc 32 has a protrusion 42.
, And the tensile force of the float 6 via the short pawl 36 acts as a moment with this as a fulcrum.

As seen in FIG. 1, since the distance from the center of the valve seat 18 to the pawl 36 and the distance to the protrusion 42 are substantially the same, the force that the float 6 pulls through the pawl 36 (of the float 6). Weight) is about 2 for the valve section 22
It will work with double the power. For this reason, the valve portion 22 of the valve disc 32 is easily separated from the valve seat 18 and is lowered together with the float 6 to open the valve.

Now, let us consider a case where the tank is shaken or tilted due to transportation or the like after returning to the normal state. At this time, the liquid level rises sharply, and at the same time, the float 6 tries to be pushed up by buoyancy. The gas in the tank and in the liquid cutoff surface can escape from the valve hole 19 having a sufficient area even if the gas is expelled due to a rapid rise in the liquid level, and does not disturb the movement of the float 6. Float 6 moves quickly, closes the valve,
Stop the liquid outflow.

In this case, the spring force of the spring 8 biasing the float 6 upward serves to close the valve when the tank is tilted too much and the efficiency of the buoyancy of the float 6 becomes poor.

[0042]

As described above, according to the present invention,
At the top of the valve body, a protrusion is provided on the opposite side of the center of the valve seat from the short pawl, and this is used as the fulcrum of the moment generated when the float pulls the valve disc through its short pawl due to its own weight. Works effectively until the valve opens, helping to pull the valve portion of the valve disc away from the valve seat, and easily pulling the valve portion away from the valve seat.

[Brief description of drawings]

FIG. 1 (a) is an overall front sectional view of a liquid cutoff valve according to an embodiment of the present invention when the liquid cutoff valve is opened, and FIG. 1 (b) is a sectional view taken along line XX of FIG. 1 (a). It is a figure.

2 (a) and 2 (b) show a valve seat plate which constitutes the valve of the liquid cutoff valve of FIG. 1, FIG. 2 (a) is a longitudinal sectional view, and FIG. 2 (b). Is a bottom view.
2 (c) and 2 (d) show the valve disc of the liquid cutoff valve of FIG. 1, FIG. 2 (c) is a longitudinal sectional view, and FIG. 2 (d) is a bottom view.

FIG. 3 (a) is an overall front sectional view of a liquid shutoff valve of a first conventional example, and FIG. 3 (b) is an enlarged view of a portion A of FIG. 3 (a).

FIG. 4 is an overall front cross-sectional view of the second conventional liquid cutoff valve when the valve is opened.

FIG. 5 is an overall front cross-sectional view of the second conventional liquid shutoff valve when the liquid level rises and the valve is closed.

FIG. 6 is an overall front cross-sectional view of a second conventional liquid shutoff valve when the valve is restarted.

7 (a) is a schematic enlarged sectional view of a valve portion of a liquid shutoff valve of a second conventional example, and FIG. 7 (b) is a top view of the valve portion of FIG. 7 (a).

[Explanation of symbols]

 2 Valve body 4 Cap 6 Float 8 Spring 10 Flange 14 Cover 16 Packing 17 Gas chamber 18 Valve seat 19 Valve hole 20 Vent passage (passage) 21 Nipple 22 Valve disc valve portion 24 Vertical rib 26 Hole 32 Valve disc 34 Top surface of float Long pawl provided on the base 36 Short pawl provided on the top surface of the float 40 Long hole 42 Projection on the top surface of the valve body 44 Valve seat plate 46 Gas chamber cap 50 Anti-rotation means 51 Recess 52 Protrusion

Claims (1)

[Claims] 1. A hollow valve body provided in an upper part of a tank for storing a liquid, and a valve body which is inserted into the hollow body of the valve body and moves up and down together with a liquid level of the liquid in the tank flowing into the valve body. A passage that communicates between the inside and the outside of the tank that opens at the top of the valve body, and a valve seat that is provided at the opening of the passage, and the valve body has a float and a float at the top of the float. A valve disc having a valve portion, which is held so as to be movable relative to the valve body, and the valve portion of the valve disc forming the valve body is in accordance with the height of the liquid surface flowing into the valve body. A liquid cutoff valve that opens and closes the passage by contacting and separating from the valve disc, wherein the valve disc is tiltably held by an upper portion of the float with a plurality of pawls, and one of the pawls is provided. The length of the valve disc is shorter than that of the other pawl, and a protrusion is provided on the opposite side of the center of the valve seat from the upper part of the valve body so that the upper surface of the valve disc abuts when the valve is opened. Liquid shutoff valve.