JPH109424A - Overturn gas emergency trip valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent core slide of a valve element, and ensure the effective opening area of a valve hole widely by arranging a guide cylinder positioned coaxially with the valve hole in a gas flow-out chamber, and protuberantly arranging a guide shaft which is slidably fit to the guide cylinder through the valve hole on the valve element. SOLUTION: An overturn gas-emergency trip valve 3 consists of a valve cabinet 30, a valve element 31, and a needle 32. A gas flow-in chamber 33, a gas flow-out chamber 34, and a valve seat 35 on which a valve hole 35a is opened are formed on the valve cabinet 30, a valve element 31 is stored in the gas flow-in chamber 33, and the needle 32 is stored on the lower side of the valve element 31. A guide cylinder 37 coaxial with the valve hole 35a and which is positioned in the gas flow-out chamber 34 is formed in the valve cabinet 30, and a guide shaft 31a which is slidably fit to a guide cylinder 37 through the valve hole 35a is protuberantly arranged on the valve element 31. The valve element 31 is core positioned surely by fitting the guide shaft, 31a with the guide cylinder 37, the diameter of the guide shaft 31a is formed in a small size comparing with that of the valve hole 35a, and thereby, the effective opening area of the valve hole 35a is ensured widely, and the flow rate of gas is increased sharply.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas appliance, and more particularly to a gas shut-off valve provided to shut off gas supply to a burner when the gas appliance falls.

[0002]

2. Description of the Related Art Conventionally, as this type of shut-off valve, as shown in FIG. 5, a gas inflow chamber a, a gas outflow chamber b, and both chambers a, b
A valve body f facing the valve seat d and a mover g that moves when the valve housing e is tilted are provided in a gas inflow chamber a of a valve housing e having a valve seat d having a valve hole c communicating with the valve housing e. It is known that the valve body f is pressed against the valve seat d by the movement of the mover g to close the valve hole c.

In this device, a boss h that is loosely inserted into the valve hole c is protruded from the valve body f so that the valve body f does not largely deviate from the valve hole c.

[0004]

In the above prior art, the gap between the valve hole c and the boss h is desirably as small as possible in order to prevent misalignment of the valve body f. If the diameter is reduced, the effective opening area of the valve hole c is reduced, and there is a problem that the flow rate of the gas is restricted. In view of the above, an object of the present invention is to provide a tipping gas shut-off valve that prevents misalignment of a valve body and that can secure a wide effective opening area of a valve hole.

[0005]

Means for Solving the Problems In order to solve the above problems,
The present invention relates to an inverted gas shut-off valve provided in a gas appliance, wherein a valve is provided in a gas inflow chamber of a valve housing having a gas inflow chamber, a gas outflow chamber, and a valve seat having a valve hole communicating the chambers. In the case where the valve body that opposes the seat and the movable element that moves when the valve housing is tilted are housed, and the valve element is pressed against the valve seat by the movement of the movable element to close the valve hole, the gas leaks out. A guide cylinder located coaxially with the valve hole is provided in the chamber, and a guide shaft is slidably fitted to the guide cylinder through the valve hole in the valve body.

According to the present invention, the valve body is reliably centered by fitting the guide shaft to the guide cylinder, and the guide shaft can be formed to have a much smaller diameter than the valve hole. A large opening area can be secured, and the flow rate of gas can be greatly increased as compared with the conventional example.

By the way, when the cross-sectional shape of the inner peripheral surface of the guide cylinder and the cross-sectional shape of the guide shaft are formed to be the same, the outer peripheral surface of the guide shaft is brought into contact with the inner peripheral surface of the guide cylinder over the entire circumference. In addition, the sliding friction increases, and the slidability of the guide shaft is liable to be deteriorated due to the entry of foreign matter, which makes the maintenance troublesome.

On the other hand, the sectional shape of the inner peripheral surface of the guide cylinder and the sectional shape of the guide shaft are different from each other,
If the outer peripheral surface of the guide shaft is formed in such a shape that the outer peripheral surface of the guide shaft comes into contact with the inner peripheral surface of the guide cylinder at a plurality of locations in the circumferential direction, the sliding friction is reduced, and the contact between the inner peripheral surface of the guide cylinder and the outer peripheral surface of the guide shaft is reduced. Since a gap is formed between the parts, foreign matter is less likely to be caught, the slidability of the guide shaft is kept good for a long time, and maintenance becomes easy.

Further, if the inner side of the guide cylinder in the guide shaft insertion direction is communicated with the gas outflow chamber, chips generated by machining the inner peripheral surface of the guide cylinder can be easily removed, which is advantageous. is there.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, reference numeral 1 denotes a gas appliance such as a fan heater or a gas stove, and a gas supply path to a burner 2 built in the gas appliance 1 is provided with a fall-off gas shut-off valve 3.
, A safety valve 4, a main valve 5 that is opened and closed by a point fire extinguishing operation, and a flow control valve 6. On the side of burner 2,
A normal-fire pilot burner 7 is provided, and a signal from a flame detection sensor 8 such as a thermocouple or a frame rod provided facing the pilot burner 7 is input to the controller 9. The valve is closed.

Instead of the normal-fire pilot burner 7, an instantaneous pilot burner for supplying gas only during the ignition operation may be provided, or the burner 2 may be ignited directly by spark discharge from the ignition electrode. In this case, the flame detection sensor 8 is provided facing the burner 2.

As shown in FIG. 2, the overturning gas shut-off valve 3 comprises a valve housing 30, a valve element 31, and a mover 32.
In the valve housing 30, a lower gas inflow chamber 33 connected to the inflow port 33a, an upper gas outflow chamber 34 connected to the outflow port 34a, and a valve hole 35a communicating the gas inflow chamber 33 and the gas outflow chamber 34 are opened. The valve body 31 is housed in the gas inflow chamber 33 so as to face the valve seat 35,
Further, a movable element 32 made of a steel ball is stored below the valve element 31. The lower surface of the gas inflow chamber 33 is provided with a cover plate 3 mounted on the valve housing 30 via a packing 36a.
6 and a concave portion 36 b is formed in the center of the lid plate 36.
Is formed, and the valve housing 30 is not inclined (FIG. 2A).
In the state (2), the mover 32 is stably supported while fitted on the periphery of the concave portion 36b. In this state,
The valve element 31 is separated from the valve seat 35, and the overturning gas shutoff valve 3 is maintained in the open state.

When the valve housing 30 is tilted by a predetermined angle or more when the gas appliance 1 is overturned, the movable element 32 comes off from the concave portion 36b as shown in FIG. 2 (B), and the valve element 31 is pushed up to hit the valve seat 35. As a result, the valve hole 35a is closed, and the gas supply to the burner 2 and the normal-fire pilot burner 7 is shut off. At this time, the burner 2 and the normal-fire pilot burner 7 are extinguished, the flame detection sensor 8 detects a misfire, the safety valve 4 is closed, the valve housing 30 returns to the non-inclined state, and the falling gas shut-off valve 3
Even if is returned to the open state, the gas supply remains shut off unless an ignition operation is performed.

The valve casing 30 is formed with a guide cylinder 37 located in the gas outflow chamber 34 and coaxial with the valve hole 35a. The guide cylinder 37 is slidably inserted into the valve body 31 through the valve hole 35a. A fitting guide shaft 31a is provided so as to protrude so that the valve body 31 does not deviate from the valve hole 35a. here,
The guide shaft 31a can be formed to have a much smaller diameter than the valve hole 35a, so that the effective opening area of the valve hole 35a can be secured wide and the gas flow rate can be increased.

In this embodiment, as shown in FIG. 3, the inner peripheral surface of the guide cylinder 37 is formed in a circular cross section, and the cross section of the guide shaft 31a is formed in a hexagonal shape. The outer peripheral surface of the guide shaft 31a contacts the surface at six locations in the circumferential direction. According to this, the sliding friction is reduced and a gap is formed between the contact portion between the inner peripheral surface of the guide cylinder 37 and the outer peripheral surface of the guide shaft 31a. A refuge,
Foreign matter is less likely to bite into the contact portion, and the slidability of the guide shaft 31a can be kept good for a long time. The cross-sectional shape of the guide shaft 31a may be a square (for example, a square) or a petal shape other than a hexagon. Further, the cross-sectional shape of the inner peripheral surface of the guide cylinder 37 may be formed in a square shape, and the guide shaft 31a May be formed in a circular shape inscribed in the square.

When the gas supply is completely shut off when the valve element 31 is pressed against the valve seat 35, the valve element 31 is pressed against the valve seat 35 by the gas pressure in the gas inflow chamber 33. Continuing, even if the valve housing 30 is set in the non-inclined state by raising the overturned gas appliance 1, the overturned gas cutoff valve 3 does not return to the open state. Therefore, in the present embodiment, a small hole 31b is formed in the valve body 31, and even when the valve body 31 is pressed against the valve seat 35, the gas inflow chamber 33 is connected to the gas outflow chamber 34 through the small hole 31b. After the safety pilot valve 4 is closed, the internal pressure of the gas outflow chamber 34 rises, and the push-up force due to the internal pressure of the gas inflow chamber 33 depends on the internal pressure of the gas outflow chamber 34. The valve body 31 is separated from the valve seat 35 by its own weight when the valve housing 30 is set in the non-inclined state by being offset by the pressing force.

The valve housing 30 is located at the open end of the inflow port 33a and the open end of the outflow port 34a.
Flanges 33b and 34b are formed as shown in FIG.
A plug 38 is attached to the flange 33b, a gas hose (not shown) is connected to the plug 38, and a connecting pipe 39 between the safety valve 4 and the flange 34b is attached.

In the drawing, reference numeral 33c denotes a filter mounted on the inflow port 33a, and reference numeral 33d denotes a packing which also serves to hold the filter 33c. Further, a communication hole 37a is provided in the back side of the guide cylinder 37.
The guide tube 37 is communicated with the gas outflow chamber 34. The communication hole 37 a is provided for easily removing chips generated during machining of the inner peripheral surface of the guide tube 37.

[Brief description of the drawings]

FIG. 1 is a diagram showing a schematic configuration of a gas appliance provided with a shut-off valve of the present invention.

2A is a cross-sectional view of an example of the shut-off valve of the present invention in a non-tilted state, and FIG.

FIG. 3 is an enlarged sectional view taken along the line III-III of FIG. 2 (A).

FIG. 4 is a sectional view taken along the line IV-IV in FIG.

FIG. 5 is a sectional view of a conventional example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Gas appliance 3 Inversion gas shut-off valve 30 Valve housing 31 Valve 31
a guide shaft 32 mover 33 gas inflow chamber 34 gas outflow chamber 35 valve seat 35
a Valve hole 37 Guide cylinder

Claims (3)

[Claims] An inverted gas shut-off valve provided in a gas appliance, wherein the gas inflow chamber has a gas inflow chamber, a gas outflow chamber, and a valve seat having a valve seat having a valve hole communicating the chambers. A valve in which a valve body facing a valve seat and a movable element that moves when the valve housing is tilted are housed, and the valve element is pressed against the valve seat by the movement of the movable element to close the valve hole. Provide a guide cylinder located coaxially with the valve hole in the outflow chamber,
A fall-off gas shut-off valve, characterized in that a guide shaft is slidably fitted to a guide cylinder through a valve hole through a valve body. 2. The cross-sectional shape of the inner peripheral surface of the guide cylinder and the cross-sectional shape of the guide shaft are different from each other, and the outer peripheral surface of the guide shaft is provided at a plurality of positions on the inner peripheral surface of the guide cylinder in the circumferential direction. 2. The overturning gas shut-off valve according to claim 1, wherein the overturning gas shut-off valve is formed in such a shape as to make contact. 3. The overturned gas shut-off valve according to claim 1, wherein a back side of the guide cylinder in the guide shaft insertion direction is communicated with a gas outflow chamber.