JP3057447B1 - Overflow prevention valve - Google Patents

Abstract

A valve body (31) reciprocating in an axial direction of a main body (11) in a cylindrical main body (11) and urged upstream by a first spring (73). The valve body (31) is provided with the first spring when the flow rate of gas flowing through the main body (11) exceeds a set value.
The overflow prevention valve, which moves to the downstream side and closes the valve against the urging force of (73), can ensure stable operation regardless of the mounting posture. SOLUTION: An annular main valve seat portion with which the valve element (31) abuts.
(52) is a cylindrical or annular auxiliary valve (51) provided on the inner periphery,
The outer peripheral flange portion (54) of the auxiliary valve (51) presses the airtight state from the downstream side by the urging force of the second spring (71) and the main body (11)
An auxiliary valve (51) seat portion formed of an annular wall continuously rising over the entire inner circumference of the auxiliary valve (51), and the auxiliary valve (31) in a state where the valve element (31) is in contact with the main valve seat portion (52). (69) a collision with the valve body (31) from the upstream side when the valve body (31) is moved downstream by a set distance together with the valve body (51).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an overflow prevention valve which closes when a gas flow rate suddenly increases and automatically shuts off a gas circuit.

[0002]

2. Description of the Related Art A conventional overflow prevention valve of this type is disclosed in Japanese Utility Model Registration No. 2508080, and is configured as shown in FIG. A tapered valve seat (12) whose diameter increases toward the upstream side is formed on the inner periphery near the upstream end of the cylindrical main body (11). A disc-shaped valve element (31) fitted into the valve seat (12) from the upstream side is provided with a braking shaft (33) projecting upstream, and the braking shaft (33) is provided with a bearing member ( It is loosely inserted in the shaft hole (25) of 23). Above brake axis (3
Flanges (35) and (35) are provided on the outer periphery of (3) in a state of being randomly eccentric.

[0003] A valve shaft (3) projecting downstream from the valve body (31).
6) is inserted into a guide cylinder (14) arranged coaxially with the main body (11), and the guide cylinder (14) is biased in the projecting direction by a spring (17). The reset shaft (16) of (13) is inserted from the downstream side. In this device, the gas plug or gas appliance is used by inserting it into the gas circuit, and is used on the upstream side (FIG. 7).
The gas supplied from the right side of the
7) → Arrangement of valve element (31) → Valve seat (12) → Gas outlet at downstream end (1
It flows along the path connected to 9) and is supplied downstream. In this state, when a gas overflow state in which the gas flow rate suddenly increases due to the detachment of a gas rubber tube (not shown) on the downstream side or the like occurs, the gas flow at this time pushes the valve element (31) to the downstream side and the valve seat (1).
Gas flow is cut off by fitting into 2).

When the valve element (31) moves toward the valve seat (12), the flanges (35) (35) mounted eccentrically on the brake shaft (33) are connected to the upstream end of the shaft hole (25). Intruding into the shaft hole (25) while colliding with the peripheral edge of the valve one after another, the time required for closing the valve from the occurrence of the overflow state to the fitting of the valve body (31) to the valve seat (12) becomes longer. . Therefore, in the overflow prevention valve of FIG. 7 in which the valve closing time is long, even if the gas circuit is rapidly opened (for example, when the solenoid valve incorporated in the gas appliance is momentarily opened), the overflow is prevented. The check valve does not malfunction. That is, when the gas circuit on the downstream side of the overflow prevention valve is suddenly opened and the gas flow rate is suddenly increased (hereinafter referred to as “pseudo overflow state”), the valve element (31) is temporarily turned off. When the pseudo-overflow state is resolved within the required valve closing time until the valve element (31) fits into the valve seat (12), the valve element (31) Is returned to the initial valve opening position by the biasing force of the spring (30), thereby preventing the overflow prevention valve from malfunctioning.

[0005]

However, in the above-mentioned conventional apparatus, when used sideways as shown in FIG. 7, the braking shaft (33) tends to be unevenly distributed below the shaft hole (25). In such a case, the lower end of the outer periphery of the flanges (35) and (35) that intrude into the shaft hole (25) is hooked on the lower peripheral edge of the open end of the shaft hole (25), so that the valve body (31) becomes difficult to move. From this, the valve body (31)
However, there is a concern that it will not be fully closed. Also, at reset, when the valve element (31) fitted into the valve seat (12) is returned to the initial position by the urging force of the spring (30), the flanges (35) and (35) are connected to the shaft holes.
(25) There is a concern that it will not be returned to the initial position by being caught on the lower peripheral edge of (25).

[0006] The present invention has been made in view of the above points,
A valve element (31) that reciprocates in the axial direction of the main body (11) within the cylindrical main body (11) and is urged upstream by a first spring; When the flow rate of gas flowing inside the valve exceeds a set value, the valve body (31) moves downstream against the urging force of the first spring to perform a valve closing operation. Another object of the present invention is to ensure stable operation regardless of the mounting posture. <Item 1>

[0007]

The technical means of the present invention for solving the above-mentioned problems is that the annular main valve seat (52) with which the valve body (31) abuts is provided around the inner periphery. A cylindrical or annular auxiliary valve, and an annular flange in which an outer peripheral flange portion of the auxiliary valve is pressed in an airtight state from a downstream side by a biasing force of a second spring and continuously rises over the entire inner periphery of the main body (11). An auxiliary valve seat formed of a wall, and when the valve element (31) moves downstream by a set distance together with the auxiliary valve in a state in which the valve element (31) is in contact with the main valve seat (52), the valve element ( 31) and a collision from the downstream side is provided ”.

The above technical means operates as follows. In the normal state, the outer peripheral flange portion of the auxiliary valve is pressed against the auxiliary valve seat formed on the inner periphery of the main body (11) from the upstream side by the second spring in an airtight state. Further, the valve element (31) abutting on the main valve seat (52) provided on the inner periphery of the auxiliary valve is pushed upstream by the first spring to be upstream from the main valve seat (52). It is maintained in a state of being separated to the side (valve open state).

In this state, if an over-outflow state of the gas occurs and the flow rate of the gas flowing through the main body (11) exceeds a set value,
The valve element (31) moves downstream against the urging force of the first spring, abuts against the main valve seat (52) on the inner peripheral side of the auxiliary valve, and performs a valve closing operation,
As a result, the auxiliary valve and the valve element (31) are connected. Next, when the valve body (31) and the auxiliary valve in the coupled state are integrally moved to the downstream side by being pushed by the gas flow, the valve body (31) collides with the contact provided on the downstream side. I do. Then, the valve body
While the (31) stops moving downstream, the auxiliary valve on the outer periphery moves downstream due to inertia, and the valve element (31) moves relative to the main valve seat (52) on the inner periphery of these auxiliary valves. It is in a state of being separated to the upstream side.

[0010] In this state, if the gas overflow state continues and the gas flow rate does not decrease, the valve element (31) pushed downstream by the gas flow is maintained in a state where it has collided with the contact.
On the other hand, the auxiliary valve that has moved to the downstream side of the valve element (31) by inertia starts returning and moving to the upstream side by the urging force of the second spring. When the auxiliary valve returns to the upstream side, the main valve seat (5
2) returns to the valve element (31) again and comes into contact with the valve element (31) to close the valve. That is, the auxiliary valve and the valve element (31) are again connected. The auxiliary valve and the valve element (31) are integrally moved to the upstream side by the biasing force of the second spring, and the outer peripheral flange portion of the auxiliary valve is formed by the inner peripheral annular wall of the main body (11). It is pressed airtightly to the valve seat. Thereby, the auxiliary valve seat formed on the inner periphery of the main body (11) is connected to the valve body (31) in the connected state.
And the auxiliary valve, whereby the outflow of gas to the downstream side is shut off.

On the other hand, a state in which the valve element (31) collides with the above-mentioned contact and is prevented from moving downstream (in this state, the main valve seat (52) of the cylindrical or annular auxiliary valve is When the flow rate of the gas in the main body (11) is reduced to an appropriate value (when the pseudo overflow state is resolved), the valve body (31) is moved to the first spring. The auxiliary valve is pushed back to the initial position on the upstream side by the urging force, and then the auxiliary valve is returned to the initial position by the urging force of the second spring. Thereby, the whole is returned to the initial state, the overflow prevention valve is maintained in the open state, and the gas is supplied to the downstream side.

As described above, according to the present invention, it is possible to cope with a pseudo-overflow state by utilizing the fact that the auxiliary valve is moved to the downstream side by inertia after the valve body (31) collides. The outer peripheral flange of the braking shaft (33) in the conventional one described above
(35) There is no need to provide a mechanism that can be caught during opening and closing operations like the peripheral edge of the shaft hole (25) through which the (35) and (35) enter and exit.

[0013]

The present invention has the following specific effects. Valve body
(31) makes it possible to cope with a pseudo-overflow condition by utilizing the auxiliary valve moving downstream due to inertia after a collision, and as described above, the brake shaft (33) There is no mechanical part that is caught during opening / closing operation, such as the outer peripheral flanges (35) and the peripheral edge of the shaft hole (25) through which the flanges (35) enter and exit. Therefore, even if the overflow prevention valve is used sideways, a smooth opening and closing operation is ensured, and a stable operation can be ensured regardless of the mounting posture. <Item 2> In the above item 1, wherein the contact is a constituent wall of a reset body (13) attached to the main body (11) so as to be able to advance and retreat in an axial direction and to be prevented from falling off, Reset body (1
The second spring is interposed in a compressed state between 3) and the auxiliary valve, and the first spring is interposed in a compressed state between the reset body (13) and the valve body (31). The valve body (31) is maintained in the closed state with the reset body (1
When 3) is moved upstream against the urging force of the first and second springs, the valve body of the reset body (13) hits the valve body.
(31) is pushed upstream to separate it from the main valve seat (52) of the auxiliary valve. Thereby, the valve element (31) can be opened and the overflow prevention valve can be reset.

<Claim 3> In the item 2 described above, in which the reset body (13) is forcibly fitted into the downstream end opening portion of the main body (11), The valve body (31) is inserted from the end opening part, and then a cylindrical or annular auxiliary valve and first and second springs are inserted. Finally, the reset body (31) is inserted into the downstream end opening part of the main body (11). When 13) is inserted, the overflow prevention valve is assembled. That is, the work of mounting all parts such as the valve element (31) can be performed from one end of the main body (11), and the assembling efficiency is improved. <Item 4> In the above items 1 to 3, "the body extending from the outer peripheral flange portion of the auxiliary valve to the upstream side may always have an inner periphery of the auxiliary valve seat portion during the movement of the auxiliary valve. In this case, the body of the auxiliary valve always moves in the inserted state on the inner periphery of the auxiliary valve seat, so that the posture and movement trajectory of the auxiliary valve during movement Can be stabilized.

[0015]

Next, embodiments of the present invention will be described. The overflow prevention valve according to the present embodiment includes a cylindrical main body (11), and a valve body (31) housed in an upstream portion thereof.
An auxiliary valve (51) having a main valve seat (52) into which the valve element (31) fits, and a reset element (1) fitted to the downstream end of the main body (11).
3) is provided. Hereinafter, details of each unit will be described. [Main body (11)] As shown in FIGS. 1 and 2, the cylindrical main body (11) is integrally formed of metal as a whole. At the upstream end of the body (10) of the main body (11), an L-shaped connecting arm extending backward from the outer periphery of the seating plate (43) having an outer diameter smaller than the inner diameter of the main body (11). (45) (45) are connected. Thereby, the periphery of the upstream end of the trunk (10) in the main body (11) and the seating plate
Gas inflow windows (41) and (41) are formed between the outer peripheral edges of (43).

An auxiliary valve (51) is provided in the middle of the main body (11) in the axial direction.
A first small-diameter portion (15) for loosely inserting the small-diameter portion is formed, and an enlarged-diameter portion (61) and a second small-diameter portion (62) subsequent to the first small-diameter portion (15) are provided downstream of the first small-diameter portion (15). Are formed, and the second small diameter portion is formed.
A reset body (13) described later is mounted on (62). [Regarding Valve Body (31)] A cylindrical wall (32) is provided around an outer peripheral portion of the valve body (31) housed near the upstream end in the main body (11), and the cylindrical wall (32) is provided. The outer periphery of the tip of (32) is tapered toward the tip. The valve shaft (3) is located downstream from the center of the valve body (31).
6) is protruding, and as shown in FIG.
Is set larger than the diameter of the seat plate (43). As a result, the outer peripheral portion of the valve element (31) at the fully open position protrudes from the outer periphery of the seating plate (43).
The gas flowing from the upstream side collides with (34).

[Auxiliary Valve (51)] A short cylinder in which a body (56) is slidably inserted into a first small-diameter portion (15) formed in the middle of the main body (11) in the axial direction. The inner peripheral surface of the downstream end of the auxiliary valve (51) has a tapered main valve seat (52) whose diameter is gradually reduced toward the downstream end, and the main valve seat (52) has a tapered main valve seat (52). The valve element (31) is fitted in an airtight state.
Also, on the outer periphery of the downstream end of the first small-diameter portion (15), there is a downstream flow from the first small-diameter portion (15) of the main body (11) to an annular wall (18) serving as an auxiliary valve seat connecting to the enlarged-diameter portion (61). An outer peripheral flange (54) abutting from the side in an airtight state is provided around. The outer diameter of the body (56) connected to the short cylindrical auxiliary valve (51) whose inner periphery is formed in a tapered surface shape is predetermined from the inner diameter of the first small diameter portion (15) of the main body (11). Gas leakage is allowed between the outer circumference of the body (56) connected to the auxiliary valve (51) and the inner circumference of the first small diameter portion (15) of the main body (11). A leak gap (38) is formed.

[Reset Body (13)] The reset body (13) attached to the downstream end of the main body (11) has a tip into which the valve shaft (36) of the valve body (31) is slidably inserted. Obstruction guide tube (6
5) and a projecting arm projecting from the outer periphery of the guide cylinder (65) in all directions.
(67) (67) and an elastically deformable engaging piece (68) (68) extending from the outer end of the protruding arm (67) (67) toward the upstream side in the main body (11).
Is provided. The engaging portions (60) (60) at the distal ends of the engaging pieces (68) (68) are connected to the second small-diameter portion (62) formed in the main body (11).
From the engagement step (63) that changes to the enlarged diameter part (61) upstream of the reset body (13).
Is prevented from escaping downstream from the subject (11).
The auxiliary valve (5) is provided between the reset body (13) and the auxiliary valve (51).
A second spring (71) for urging the valve body (1) to the upstream side is interposed, and the valve body (31) is provided between the reset body (13) and the valve body (31).
And a first spring (73) weaker than the second spring (71) is interposed.

[Assembly work] Next, the work of assembling the overflow prevention valve according to the above-described embodiment using the above-described parts will be described. When assembling the overflow prevention valve, the main body (1) is so positioned that the downstream end opening (81) of the main body (11) faces upward.
1) is held in a vertical position. Next, the valve element (31) is inserted from the downstream end opening part (81) of the main body (11), and thereafter, the body part (56) of the auxiliary valve (51) is inserted from the downstream end opening part (81). At the same time, the body portion (56) is loosely inserted into the first small diameter portion (15) in the main body (11). Then, the outer peripheral flange protruding on the outer periphery of the downstream end of the auxiliary valve (51)
The (54) hermetically contacts the annular wall (18), which changes from the first small diameter portion (15) on the main body (11) side to the enlarged diameter portion (61), and is engaged.

Next, a coiled first spring (73) is inserted from the downstream end opening (81) of the main body (11), and the first spring (7) is inserted.
3) is extrapolated to the valve shaft (36) of the valve body (31). Further, a coil-shaped second spring (71) is inserted from the downstream end open portion (81) of the main body (11), and the second spring (71) is inserted along the downstream end surface of the auxiliary valve (51). Abut. Next, the reset body (13) is
(68) Forcibly fitted into the main body (11) from the (68) side,
An engaging step in which the engaging portions (60) (60) at the tips of the engaging pieces (68) (68) change from the engaging pieces (68) (68) of the main body (11) to the enlarged diameter portion (61). Department (6
Engage with 3). Thereby, the assembly of the overflow prevention valve according to the present embodiment is completed. In this case, the valve (3
All parts such as 1) can be inserted from the downstream end opening (81) of the main body (11) to assemble the overflow prevention valve, so that each part is assembled from both ends of the main body (11). , Subject
There is no need to perform the work of incorporating parts into the main body (11) while turning the (11) upside down, and the assembling work can be performed easily.

[Actual Operation] The overflow prevention valve (A) is
For example, as shown in FIG. 4, it is used by being incorporated in a gas stopper (91). When the overflow prevention valve (A) is in an operable state, the valve body (31) is maintained in an open state in which the valve body (31) escapes upstream from the auxiliary valve (51) as shown in FIG.

In this state, when an overflow state occurs and the gas flow rate in the overflow prevention valve (A) increases, the gas flow causes the valve element (31) to resist the urging force of the first spring (73). Is pushed downstream. When the valve element (31) is fitted into the valve port (524) surrounded by the main valve seat (52) of the auxiliary valve (51), the auxiliary valve (51) and the valve element (31) Is the first spring (73) and the second
The spring (71) starts moving integrally downstream while compressing it. When the auxiliary valve (51) and the valve element (31) move further downstream, as shown in FIG. 6, the valve shaft (36) of the valve element (31) has a guide hole formed in the reset element (13). (66) Back wall (6
9), whereby the valve element (31) is forced to escape from the main valve seat (52) of the auxiliary valve (51) to the upstream side. Valve body
(31) escapes from the main valve seat (52) to the upstream side because the auxiliary valve
(51) moves to the downstream side by inertia, while the back wall (69) of the guide hole (66) of the reset body (13) functioning as a contact and the valve shaft
This is because the valve body (31) is stopped by the collision (36) (see FIG. 6). When the overflow state continues in the state of FIG. 6 in which the tip of the valve shaft (36) is in contact with the inner wall (69) of the guide hole (66), the valve element (31) is downstream of the gas in the overflow state. Fig. 6
While the auxiliary valve (51) is returned to the upstream side by the urging force of the second spring (71). Then, during this return movement, the part of the main valve seat (52) of the auxiliary valve (51) is
After that, the auxiliary valve (51) and the valve element (31) move integrally upstream. Furthermore, these auxiliary valve (51) and valve body (3
When (1) moves to the upstream side, the outer peripheral flange (5) of the auxiliary valve (51)
4) is pressed air-tight against the annular wall (18) on the inner periphery of the main body (11), whereby the reset body (13) and the auxiliary valve (51) are both kept at the closed position as shown in FIG. Thus, the gas flow path is shut off.

On the other hand, when the flow rate of the gas in the main body (11) decreases to an appropriate value in a state where the valve body (31) collides with the reset body (13) and is prevented from moving downstream, the pseudo When the overflow state is eliminated), the valve element (31) is pushed back to the portion of the seating plate (43) on the upstream side by the biasing force of the first spring (73), and then the auxiliary valve is also biased by the biasing force of the second spring. It is returned to the initial position. Thereby, the whole is returned to the initial state, the overflow prevention valve is maintained in the open state, and the gas is supplied to the downstream side.

In this embodiment, the valve element (31) is connected to the reset element (13).
This makes it possible to cope with a pseudo-overflow state by utilizing the fact that the auxiliary valve slightly moves downstream due to inertia after a collision. Therefore, there is no inconvenience such as the outer peripheral flanges (35) and (35) of the braking shaft (33) and the peripheral edge of the shaft hole (25) through which the braking shaft (33) is caught at the time of opening / closing operation as described above, and the overflow prevention valve is provided. A smooth opening and closing operation is ensured both when used horizontally and vertically.

In the above embodiment, a short cylindrical auxiliary valve (51) having a tapered main valve seat (52) inside is employed. However, the auxiliary valve (51) is a flat annular plate. The annular plate may be formed so that the outer peripheral portion of the annular plate is brought into contact with the annular wall (18) serving as an auxiliary valve seat in an airtight state, and the valve body (31) is brought into contact with the inner peripheral upstream surface of the annular plate. Good.

[Brief description of the drawings]

FIG. 1 is a sectional view of an overflow prevention valve according to an embodiment of the present invention in an open state.

FIG. 2 is a diagram of the overflow prevention valve according to the embodiment of the present invention as viewed from an upstream side;

FIG. 3 is a view of the overflow prevention valve according to the embodiment of the present invention as viewed from a downstream side.

FIG. 4 is a sectional view showing an example of use of the overflow prevention valve according to the embodiment of the present invention.

FIG. 5 is a sectional view of the overflow prevention valve according to the embodiment of the present invention in a closed state.

FIG. 6 is an operation explanatory diagram of the overflow prevention valve according to the embodiment of the present invention.

FIG. 7 is an explanatory view of a conventional example.

[Explanation of symbols]

(11) ・ ・ ・ Main body (18) ・ ・ ・ Circular wall (31)
・ ・ ・ Valve (51) ・ ・ ・ Auxiliary valve (52) ・ ・ ・ Main valve seat (71)
... Second spring (73) ... First spring

Claims (4)

(57) [Claims] 1. A valve body (31) reciprocating in an axial direction of a main body (11) within a cylindrical main body (11) and urged upstream by a first spring, When the flow rate of the gas flowing through the main body (11) exceeds a set value, the valve body (31) moves downstream against the urging force of the first spring to perform a valve closing operation. In the above, a cylindrical or annular auxiliary valve having an annular main valve seat portion (52) which is in contact with the valve element (31) provided on the inner periphery thereof, and an outer peripheral flange portion of the auxiliary valve is formed of a second spring. An auxiliary valve seat portion formed of an annular wall which is pressed airtightly from the downstream side by the urging force of the downstream side and continuously rises over the entire inner periphery of the main body (11); and the valve element (31) is the main valve. An overflow prevention valve, comprising: hitting the valve element (31) from the downstream side when the auxiliary valve moves downstream by a set distance together with the auxiliary valve in contact with the seat (52). 2. A reset body (13) according to claim 1, wherein said contact is movable in an axial direction with respect to said main body (11) and is attached in a state of being prevented from falling off. A wall, wherein the second spring is interposed in a compressed state between the reset body (13) and the auxiliary valve, and the first spring is provided between the reset body (13) and the valve body (31). An overflow prevention valve with a spring interposed in a compressed state. 3. The overflow prevention valve according to claim 2, wherein the reset body (13) is forcibly fitted into a downstream end opening of the main body (11). 4. The overflow prevention valve according to claim 1, wherein the body extending from the outer peripheral flange portion of the auxiliary valve to the upstream side is moved during the movement of the auxiliary valve. An overflow prevention valve which is always kept inserted in a space surrounded by the inner periphery of the auxiliary valve seat.