JPS5869322A - Safety device of forced supply or exhaust type gas burner - Google Patents

Abstract

PURPOSE:To improve the safety by a method wherein the burner is on-off controlled by sensing, with an air pressure switch, whether the air flow suitable for existing combustion intensity is supplied or not in whatsoever combustion intensity stage the burner may be. CONSTITUTION:In case that a forced supply type gas burner is concerned, a pressure detecting hole 5 formed at one end of a pressure pipe 4, the other end of which is connected to the diaphragm chamber 6 of a diaphragm main body 15 consisting of the air pressure switch A, is provided within a sirocco fan 1 housed in a fan casing 13 in such a manner that the hole 5 is open toward to direction of the discharge port 3a of the discharge pipe 3 of suction air. The regulation chamber 7 of an air flow controller B, within which a valve body 8 pressingly energized by means of a spring 9 toward the direction for throttling the draft cross-sectional area of a suction port 11 is housed. If the amount of suction air runs short of that suitable for the amount of gas supplied because of the failure of the fan 1 or the like, a switch 16 is turned OFF due to the lowering of the negative pressure at the pressure detecting hole 5, resulting in stopping the operation of the burner.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a safety device for a forced-feed, exhaust-type gas combustor.

Conventionally, a pressure detection port of a pressure guide pipe of a pressure switch is inserted into one of the suction passage or the discharge passage, and the wind pressure generated by the blower fan is guided to the diaphragm chamber through the pressure detection port and the pressure guide pipe.
The change in wind pressure is converted into the displacement of the diaphragm, and the IJ e-switch is turned on and off based on this displacement, and if the specified wind pressure cannot be obtained, that is, the amount of air supplied to the combustion chamber completely burns all of the supplied gas. Various safety devices have been proposed that prevent incomplete combustion by turning off the limit switch and stopping the gas supply when the gas is insufficient. It is extremely difficult to set and control the amount of air blown to an arbitrary value, and it has not been done in practice. Therefore, it could not be used in a forced-feed, exhaust-type gas combustor of the capacity switching type, in which the combustion capacity is changed in stages or in a coordinated manner.

This invention solves this drawback, and when the amount of gas supplied for combustion changes by switching the combustion capacity, and the blowing capacity of the blower fan is also changed at the same time, the air flow rate changes. The wind pressure changes with changes in the airflow volume, but by installing an airflow regulator that automatically limits the airflow volume on the suction side of the fan, the cross-sectional area of the suction passage is increased when the airflow volume is large, and the When the cross section 1III of the suction passage is made smaller,
Is the amount of air suitable for the combustion capacity being sent to the combustion chamber of the gas combustor, regardless of the combustion capacity stage, by obtaining close wind pressure regardless of the size of the air blowing capacity, that is, the amount of air blown? The limit switch is designed to detect wind pressure and operate at a wind pressure value close to the limit switch pipe.

Embodiments of the present invention will be described below based on the drawings.

Figure 1.2 shows an embodiment in which the present invention is applied to a forced air gas combustor, and (1) shows a fan case (1).
Sirocco fan installed in 8+, 7 motor (
2) The sirocco fan (1) is rotated so that the pressure detection port (6) at one end of the impulse pipe (4) is directed toward the discharge port (8&) of the supply air discharge pipe (3). The other end of the pressure impulse pipe (4) is connected to the diaphragm chamber (6) of the diaphragm body (B) that completely constitutes the wind pressure (4). (C) is a gas combustor, and the discharge pipe (3) is connected to its air supply port.
7) The valve body (8) is attached to the intake port (8b) of the adjustment chamber (7) by the spring (9) in the direction of the valve seat (toward), that is, the intake port αη.
The air flow rate regulator (B) is connected to the suction pipe (intake pipe). still(
b) This is the surrounding wall of the control room (7).

Figure 5 shows the air volume (Q) obtained by the sirocco fan (1).
The air volume-wind pressure curve obtained by putting all values of and negative wind pressure (P) on the horizontal and vertical axes, the air volume-wind pressure curve obtained when curve D is crossed, and the curve a , G are the intake resistance −at when the intake resistance is small and when it is large, respectively.
show. Therefore, when the combustion capacity is switched to small and the amount of gas supplied for combustion is reduced, a 7-amp motor (2 ), the rotational speed of the sirocco fan (1) is lowered, and the amount of air supplied to the combustion chamber by the sirocco fan (1) is reduced. Due to the throttling action of the gap between the air volume regulator (the valve element (8) of the seagull), the distance between the two becomes small to a.As a result, the intake resistance increases. In this state, the obtained air supply air volume becomes Q2, the obtained negative pressure of the pressure detection port (5) becomes P2, and the negative pressure P2 air *
* Due to the movement of the valve body (8) of the joint device t (B), that is, due to the decrease in the supply air volume, the negative pressure at the intersection N of the curve E and the curve 1 is reduced pg /
It is lifted more.

Next, when the combustion capacity is switched from small to large and the amount of gas provided for combustion is increased, the rotation speed etc. of the sirocco fan (1) are increased in the same way as above, and as a result, the rotation speed etc. of the sirocco fan (1) are increased. This increases the amount of air supplied to the combustion chamber of the gas burner (C). As the amount of air supply increases, the differential pressure generated across the valve body (8) due to the throttling action of the intake port (9) becomes large, and the valve body (8) resists the biasing force of the spring (9). 8) # Valve seat O0 moves away and the gap becomes large as b, and this crosses with the ventilation @y. The negative pressure becomes Pl, which is lower than the negative pressure p11 at the intersection M between the song @D and the song 1iG due to the movement of the negative pressure Plid valve body (8), that is, due to the increase in the amount of air supply.

As mentioned above, when the capacity of the sirocco fan (1) is full and small, the negative pressure at the pressure detection port (5) becomes Pl and PIB, respectively.
Since the values of PI, P, and a can be set close to each other, they can be kept within the same on (off) range of the limit switch <16+ of the pressure switch (4).

Next, exhaust gas is suppressed during combustion, which may cause blockage of the exhaust stack or malfunction of the syrup fan (1) (7 motor (2)). When the pressure is no longer sent to the pressure detection port (5), the negative pressure at the pressure detection port (5) is
IliIE moves in a smaller direction and the distance traveled by the valve body (8) to the valve seat αQ disappears, and the pressure becomes smaller than the negative pressure P2, the limit switch a6) is turned off, and the combustion gas enters the combustion chamber. Stop supply. In this way, safety is ensured by using the existing limit switch to control the supply and disconnection of gas to ensure the required amount of air supply.

Fig. 3 shows a different embodiment of the present invention, in which the valve body (8) of the air volume regulator (B) in the above embodiment is replaced with an elastic sheet (rotator) made of rubber or the like as shown in Fig. 3. ) is formed in the center of the intake hole Q81, and a radial J hole (2)) is formed around the intake hole Q81.
lη is attached to the suction port (8b) shown in Fig. 1 so that the suction port (8b) and the suction port (8b) form a substantially concentric circle, thereby automatically throttling and adjusting the air supply amount. This is what I did. In this case, as in the above embodiment, when the rutting capacity is large, the differential pressure generated before and after the elastic sheet (B) caused by the squeezing by the air intake hole (G) by the sirocco fan (1) is large, and the elasticity increases. In the intake hole 081 of the seat (B), the notch (2) part is greatly pressed and curved in the direction of the sirocco fan (1), and -7~ is expanded to form the intake hole □□□
The diameter of C and the area of the intake port (8b) are larger than that of d. When the combustion capacity is small, the degree of curvature is small, and similarly, the diameter of the intake hole (g) is smaller than C, and the area of the intake port (8b) is smaller. Even if the air supply amount is changed, the negative pressures P I XP 2' of the respective pressure detection ports (5) can be maintained at close values in the same manner as described above.

In the embodiment described above, the pressure detection port (6) and the Shirotsuko fan (1
) was inserted and installed directly inside the blade of the blade toward the discharge port (8a) to apply air flow pressure and obtain a large negative pressure. (8)
It may be inserted and disposed on the suction side between the fan, or it may be disposed on the discharge side of the blower fan, in which case the sensed wind pressure will be positive. In addition, the safety device according to the present invention can be applied to the forced exhaust type, in which case the inlet (8b) k is connected to the exhaust duct of the gas combustor (Q, or is connected to the F! suction pipe side) 111 and connect it to the exhaust duct of the C121k gas combustor (C) on the side of the blower fan, and connect it to the exhaust duct of the gas combustor (C).
If the intake pipe on the Bl side is connected to the Mi port of the gas combustor (C), the flow volume of the air flowing through the intake pipe Q21 and the discharge pipe (3) is the same, so the same effect as described above can be obtained. It will be done.

As described above, this invention has a simple configuration in which an air volume adjustment device with an automatic throttling function is provided on the intake side of the blower fan, and the blowing capacity of the blower fan can be adjusted by switching the combustion capacity between large, medium, and small. When the air pressure changes, the intake resistance can be changed from small to medium to large using automatic throttle to maintain a value close to the wind pressure at the pressure detection port, so the intake resistance can be adjusted accordingly regardless of the combustion capacity stage. Whether or not air is being sent to the combustion chamber can be detected using a single existing limit switch based on the magnitude of wind pressure at all pressure detection ports, so exhaust can be suppressed and the exhaust stack can be controlled regardless of the combustion capacity stage. When a blockage occurs, the limit switch of the wind pressure switch is turned on and off to control the supply and disconnection of seven gases to ensure safety, making it a practical invention.

[Brief explanation of the drawing]

Figure 1 is a schematic configuration diagram of the present invention installed in the air supply volume of a forced-feed, exhaust type gas combustor, Figure 2 is an enlarged view of the part, Figure 3
The figure is an enlarged view of the moving parts showing another embodiment, FIG. q is a front view of the moving part, and FIG. 3 is a diagram showing the relationship between air volume and wind pressure. (1)...Blower fan (white rough fan), (s)
...Discharge pipe, (4) ... Impulse pipe, (5) ... Pressure detection port, (7) ... Control chamber, (8) ... Valve body, (9) ...
...spring, QO...valve seat, 05)...diaphragm body, (b)...elastic sea), Oa...intake hole, 09)...notch, (4)...・・Wind pressure switch, (
B)...Air volume regulator. Patent applicant Paloma Industries Co., Ltd.

Claims (1)

[Scope of Claims] / In a device that forcibly supplies and exhausts a gas combustor by using all valves of the blower fan, one end of the pressure pipe is inserted into the blower fan suction passage or the discharge passage with the pressure detection port fully open. The other end is connected to the diaphragm chamber that constitutes the wind pressure switch, and an air volume regulator is installed in the suction passage of the blower fan to automatically change the cross-sectional area of the suction passage according to the air volume. , safety device for exhaust type gas combustor. 2. The cross section of the suction passage is fully automatically changed, and the valve body is installed so that it is pressed against the valve seat provided in the control chamber, and the valve body is connected to the suction port of the control chamber. A safety device for a forced-feed, exhaust-type gas combustor according to claim 1, which has a structure in which a valve seat provided in a valve seat is brought into contact with and separated from a valve seat by the suction force of a feeding fan. As a structure that automatically changes the cross-sectional area of the suction passage, an intake hole is bored in the center and radial cuts are made around the suction hole. Safety device Wt for forced exhaust type gas combustion according to claim 1, wherein the diameter of the intake hole is changed by suction force.
,,1