JP2000205521A - Pilot nozzle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a pilot nozzle in which a needle can slide again even when the needle adheres to an ejection opening by providing a needle coupled with a diaphragm while being urged in the direction of the ejection opening to be inserted into the ejection opening and removed therefrom freely thereby preventing the ejection opening from being clogged. SOLUTION: A needle 13 is inserted into an ejection opening 10a to penetrate a diaphragm 15 perpendicularly and to pass through a plunger opening and fitted to one end of a plunger 12 extending to the outside of a cover member 9. When gas is not introduced into a gas chamber 8a, a compression spring 14 urges the diaphragm 15 in the direction of an arrow (a) and the needle 13 is inserted into the ejection opening 10a. When a pilot flame is ignited, gas is introduced into the gas chamber 8a. Consequently, pressure in the gas chamber 8a increases to press the diaphragm 15 and move the diaphragm 15 while resisting against the spring force of the compression spring 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pilot nozzle for supplying gas to a pilot burner provided in a gas combustion device such as a gas water heater or a fryer for burning a pilot flame for igniting a main burner.

[0002]

2. Description of the Related Art Conventionally, there is a pilot nozzle for supplying gas to a pilot burner as shown in FIGS. The pilot nozzle 40 includes a substantially cylindrical case member 43 and a substantially cylindrical nozzle block 10 having a gas ejection port 10 a screwed to one end of the case member 43. The other end of the case member 43 has O
By attaching the ring 54 and screwing the cover member 44, a gas chamber 43 a is formed inside the case member 43. A plunger 46 is slidably provided in the gas chamber 43a through the cover member 44. One end of the plunger 46 on the gas chamber 43a side is provided with a spout 1.
A needle 47 having a detachable thickness is clamped in 5a. A gas passage 43c and a gas inlet 43b are provided on a side surface of the case member 43 so as to communicate with the gas chamber 43a. The gas inlet 43b is connected to the gas supply member 5 made of a cylinder, and the gas in the tank 3 is introduced into the gas chamber 43a. Note that a valve 4 is provided in the gas supply member 5 between the tank 3 and the gas inlet 43b, and gas is introduced / not introduced by opening and closing the valve 4.

[0003] An O-ring 55 is provided in close contact with the plunger 46 at an end of the cover member 44 on the gas chamber 43a side by an O-ring retainer 50 fitted to the cover member 44. At the other end of the plunger 46, a knob 46b is provided, and at the center of the plunger 46, a retaining ring 51 is fitted. Plunger 46
A compression spring 45 is stretched between the retaining ring 51 and the flange 43d provided at the center of the gas chamber 43a.
Is pressed against the O-ring retainer 50. This allows the plunger 46 to move the needle 47
It is retracted and held at the position where it has been pulled out of.

The pilot burner 20 has a substantially cylindrical mixture passage 25 formed therein. At one end of the mixture passage 25, a flame port (not shown) is provided, and at the other end, a nozzle inlet 23 which opens in a circular shape is provided. A pilot nozzle 40 is mounted via the nozzle block 15. Further, two air introduction ports 24 are provided near the nozzle inlet 23 of the mixture passage 25.

[0005] As shown in FIG.
0, the gas introduced from the gas inlet 43b is opened by opening the valve 4, as indicated by the arrow p.
After passing through the nozzle block 10 in the direction of arrow q, it is ejected from the ejection port 10a (arrow r). Then, the mixture is mixed with the air (arrow s) introduced from the air introduction port 24 and becomes an air-fuel mixture. The air-fuel mixture flows through the air-fuel mixture passage 25 in the direction of the arrow t.

[0006] As shown by an arrow s in FIG. 5, the air entering from the air inlet 24 flows into the mixture passage 25 while also contacting the tip of the nozzle block 10. However, the introduced air contains oil and dust, and causes the dust X to adhere to the tip of the nozzle block 10. If the pilot nozzle 40 has been used for a long period of time, the jet port 10a will be clogged with the dust X, and the pilot flame will not burn. When the ejection port 10a is clogged, the operator pushes the knob 46b in the direction of the arrow u in FIG. 5 against the elastic force of the compression spring 45. Then, as shown in FIG. 6, the needle 47 is inserted into the ejection port 10a, and the attached dust X can be removed.

[0007]

However, in the conventional pilot nozzle, the operator operates the needle to remove dust from the ejection port. For this reason, it is necessary for the operator to periodically clean the ejection port, and the dust cleaning operation is complicated. Further, since the operator needs to frequently operate the needle, it is necessary to provide the gas combustion device with a structure that allows the plunger to be easily operated, resulting in a structural limitation.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to eliminate the need for an operator to perform dust cleaning work, prevent clogging of an ejection port, and prevent a needle from sticking to an ejection port. It is still another object of the present invention to provide a pilot nozzle having a structure that allows the needle to slide again.

[0009]

According to a first aspect of the present invention, there is provided a pilot nozzle including a case having a diaphragm chamber therein, wherein the diaphragm is arranged so as to partition the diaphragm chamber into two rooms, and one of the two rooms is provided. A needle provided in the case with a gas inlet for supplying gas to the chamber and a jet port for jetting and supplying gas from one of the rooms to the pilot burner, and connected to the diaphragm and urged in the direction of the jet port. When the gas is introduced into one chamber from the gas inlet and pressurized, the needle is pulled out of the nozzle against the urging force from the diaphragm. Features.

According to a second aspect of the present invention, in the pilot nozzle, a compression spring is disposed between the case and the diaphragm in the other of the two rooms, and the diaphragm is urged by the compression spring. And

According to a third aspect of the present invention, in the pilot nozzle, the needle is connected to the diaphragm via a plunger, and the ejection port, the needle, and the plunger are arranged in a straight line.

According to a fourth aspect of the present invention, in the pilot nozzle, the case is provided with a plunger port on the other room side, and the plunger is arranged to protrude outside the case via the plunger port.

[0013]

Embodiments of the present invention will be specifically described below with reference to the drawings. FIG. 1 is a sectional view showing a main part of an embodiment of a pilot nozzle according to the present invention, and FIG.
FIG. 2 is a sectional view taken along line II-II of FIG. FIG. 3 is a plan view showing the operation state of the pilot nozzle of FIG. 1, and FIG. 4 is a sectional view taken along the line IV-IV of FIG.

In FIG. 1 to FIG.
Is for supplying gas to a pilot burner 20 which is provided in a gas combustion device such as a gas water heater or a fryer and burns a pilot flame Y for igniting a main burner (not shown). The pilot nozzle 1 includes a case member 8 and a cover member 9 having a substantially bowl-shaped space inside.
Are fixed by screws 7 so that their openings are closely in the vertical direction. A plunger chamber is formed by the inner surfaces of the case member 8 and the cover member 9.

An O-ring 15 provided on the outer periphery of the diaphragm 15 is provided on the contact surface between the case member 8 and the cover member 9.
A diaphragm 15 is provided in the plunger chamber by sandwiching a. The diaphragm 15 is made of compressible nitrile rubber, silicon or fluorine rubber, and divides the plunger chamber into a gas chamber 8a on the case member 8 side and a spring chamber 9a on the cover member 9 side. Since the O-ring 15a is sandwiched between the contact surfaces of the case member 8 and the cover member 9, the gas chamber 8a and the spring chamber 9
Airtightness with a is maintained.

At the top of the case member 8, there is provided a gas inlet 8b into which a female screw is threaded. A gas supply member 5 composed of a pipe or a hose for supplying gas is screwed into the gas inlet 8b. The gas inlet 8b communicates with the gas chamber 8a via the gas passage 8c, and the gas in the tank 3 passes through the gas supply member 5, the gas inlet 8b and the gas passage 8c via the valve 4, and passes through the gas chamber 8a. It can be introduced to

A female screw hole is formed in a surface of the case member 8 facing the diaphragm 15, and a substantially cylindrical nozzle block 10 is screwed therein. Nozzle block 10
Has an inner diameter of about 4 mm and narrows toward the tip, and the tip has an inner diameter of 0.3 to 0.9 mm depending on the type of gas.
Is formed.

A needle 13 having a diameter of about 0.05 mm smaller than the inner diameter of the jet port 10a is inserted into the jet port 10a. The needle 13 is inserted into the nozzle block 10, penetrates the diaphragm 15 at a right angle, passes through a plunger port 9 b formed in the cover member 9, and
Is fitted to one end of a plunger 12 extending outside. Then, the ejection port 10a, the needle 13, and the plunger 12 are arranged on a straight line.

A spring retainer 16 made of a circular plate is inserted into the plunger 12 in the spring chamber 9a. Compression spring 1 mounted on plunger 12 and stretched between cover member 9 and spring retainer 16
4, the spring retainer 16 is moved to the diaphragm 15
Is pressed against. In addition, the protrusion of the compression spring 14 is prevented by providing a protrusion near the position where the compression spring 14 of the spring retainer 16 contacts the inside of the cover member 9. Further, a diaphragm retainer 17 made of a circular plate is inserted into the plunger 12 in the gas chamber 8a. The diaphragm retainer 17 is in close contact with the diaphragm 15 by a retaining ring 18 fitted on the plunger 12. By the compression spring 14 and the retaining ring 18,
Since the spring retainer 16 and the diaphragm retainer 17 sandwich the diaphragm 15, the gas chamber 8a near the plunger 12 and the spring chamber 9a are kept airtight.

The pilot burner 20 is made up of two plate members, each having a semi-cylindrical concave air-fuel mixture passage 25 and two burner members 21 attached vertically. At one end of the burner member 21, four flame ports 22 are provided radially.
The other end is a nozzle inlet 23 which is a cylindrical opening, and is attached to the nozzle block 10 so that the pilot burner 20 is attached to the pilot nozzle 1. The burner member 21 near the nozzle inlet 23 is provided with an air inlet 24 for introducing air into the mixture passage 25.

The operation of the pilot nozzle 1 of this embodiment will be described. When the gas is not introduced into the gas chamber 8a, the compression spring 14 urges the diaphragm 15 in the direction of arrow a as shown in FIG. The plunger 12 connected to the diaphragm 15 is indicated by an arrow a.
In the direction of. At this time, the needle 13 is in a state of being inserted into the ejection port 10a. Needle 1
Even when 3 is inserted into the ejection port 10a, the end 12a of the plunger 12 protrudes outside the cover member 9 via the plunger opening 9b formed in the cover member 9. In this state, even if dust X adheres to the tip of the nozzle block 10, the ejection port 10a does not become clogged.

Next, the case where the pilot flame Y is ignited will be described. First, the valve 4 is opened, and gas is introduced from the tank 3 into the gas inlet 8b via the gas supply member 5. The gas is
As shown in the figure, the gas flows in the gas passage 8c in the direction of arrow d and enters the gas chamber 8a. Then, the pressure in the gas chamber 8a is increased, the diaphragm 15 is pressed in the direction of arrow f, and moves laterally against the elastic force of the compression spring 14. At this time, the pressure in the gas chamber 8a is about 280 mmH _{2 in} the case of LP gas.
O. As the diaphragm 15 is pressed in the direction of arrow f, the plunger 12 slides in the direction of arrow g. At the same time, the needle 13 fitted on the plunger 12 also moves in the direction of arrow g. And needle 1
3 is withdrawn from the ejection port 10a. When the ejection port 10a is opened, the gas in the gas chamber 8a is changed to an arrow e and an arrow j.
And is ejected from the ejection port 10a in the direction of arrow k.

When the gas is ejected from the ejection port 10a, the air pressure near the ejection port 10a decreases, and the air introduction port 24
, Air flows in the direction of arrow m. Then, the gas is mixed with the gas jetted from the jet port 10a to form an air-fuel mixture, moves through the air-fuel mixture passage 25 in the direction of arrow n, and jets from the flame port 22 as indicated by arrow c. The pilot gas Y is ignited by igniting the air-fuel mixture ejected from the flame port 22 with a spark plug (not shown). Gas chamber 8a by valve 4
When the introduction of gas into the gas chamber 8 is stopped, the pressure in the gas chamber 8a is reduced, and the diaphragm 15 is urged in the direction of arrow a shown in FIG. And
The needle 13 moves together with the plunger 12 in the direction of the arrow a, and is inserted into the ejection port 10a.

The air that has entered through the air inlet 24 flows toward the mixture passage 25 while also contacting the tip of the nozzle block 10 as shown by an arrow m in FIG. However, the introduced air contains oil and dust, and causes the dust X to adhere to the tip of the nozzle block 10. According to the invention of this embodiment, the introduction / non-introduction of the gas into the gas chamber 8a causes the needle 13 to move the ejection port 10a.
And the needle 13 sweeps the ejection port 10a. This eliminates the need for the operator to clean the pilot nozzle 1 with dust and prevents the pilot nozzle 1 from being clogged.

If the needle 13 is fixed to the jet port 10a due to dust X without using the pilot nozzle 1 for a long time, the portion of the plunger 12 protruding from the cover member 9 is tooled with a tool such as pliers. By pulling, the needle 13 can be made slidable again.
The retraction of the plunger 12 is an operation performed only in an emergency when the needle 13 cannot slide. For this reason, it is not necessary to provide a knob at the end 12a of the plunger 12 or to equip the gas-fired device with a door that can be easily opened and closed so that the plunger 12 can always be pulled. Restrictions are reduced.

In this embodiment, the gas introduced into the gas chamber 8a is propane gas supplied from the tank 3. However, the gas is not limited to propane gas, but may be any gas that can be used for gas combustion equipment, and may be city gas supplied by piping regardless of the tank 3.

[0027]

According to the present invention, when gas is not introduced into the gas chamber, the gas is urged by the diaphragm, and the needle is inserted into the ejection port. When gas is introduced into the gas chamber for igniting a pilot flame, the gas chamber is pressurized, whereby the diaphragm is pressed against the urging force, and the needle is pulled out from the ejection port. That is, the introduction / non-introduction of the gas into / from the gas chamber causes the needle to slide / insert / eject the ejection port, and the needle cleans the ejection port. This eliminates the need for the operator to clean the pilot nozzle, and prevents the pilot nozzle from being clogged.

Further, the plunger protrudes outside the case, and the plunger is slidably disposed in the plunger opening. For this reason, when the needle sticks to the ejection port without using the pilot nozzle for a long time, the needle can be slid again by towing the portion of the plunger projecting from the case.
The retraction of the plunger is an operation performed only in an emergency when the needle cannot slide. For this reason, it is not necessary to provide a structure that allows the plunger to be always towed in the gas-fired device, and the structural restrictions of the gas-fired device are reduced.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part showing an embodiment of a pilot nozzle of the present invention.

FIG. 2 shows a state in which a case part of FIG. 1 is removed; II-II
It is principal part sectional drawing seen from the line arrow.

FIG. 3 is a plan view showing an operation state of the pilot nozzle of FIG. 1;

FIG. 4 is a sectional view taken along line IV-IV of FIG. 3;

FIG. 5 is a sectional view of a main part showing a conventional pilot nozzle.

FIG. 6 is an operation explanatory diagram of FIG. 5;

[Explanation of symbols]

 1 ... Pilot nozzle 3 ... Tank 4 ... Valve 5 ... Gas supply Member 8: Case member 8a: Gas chamber 8b: Gas inlet 9: Cover Member 9a Spring chamber 10 Nozzle block 12 Plunger 13 Needle 14 ········ Compression spring 15 ······· Diaphragm 15a ······ O-ring 20 ·········· Pilot burner 24 ····· .... Air inlet

Claims (4)

[Claims] 1. A pilot nozzle for supplying gas to a pilot burner of a gas-fired device, the pilot nozzle including a case having a diaphragm chamber therein, and having a diaphragm so as to divide the diaphragm chamber into two chambers. A gas inlet for supplying gas to one of the two chambers, and an outlet for ejecting and supplying gas from the one chamber to the pilot burner are provided in the case; And a needle urged in the direction of the jet port is provided in the jet port so as to be freely inserted into and removed from the jet port, and when gas is introduced from the gas inlet to the one chamber and pressurized, the pressure from the diaphragm is reduced. A pilot nozzle in which the needle is pulled out of the ejection port against the urging force. 2. In the other of the two rooms,
The pilot nozzle according to claim 1, wherein a compression spring is disposed between the case and the diaphragm, and the diaphragm is urged by the compression spring. 3. The pilot nozzle according to claim 1, wherein said needle is connected to said diaphragm via a plunger, and said jet port, said needle and said plunger are arranged in a straight line. 4. The case is provided with a plunger port on the other room side, and the plunger is arranged to protrude outside the case via the plunger port. Pilot nozzle as described.