JPH0152631B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a damper for an exhaust bypass stack attached to an exhaust system that discharges dust-containing harmful gases generated from equipment, such as a ventilation mechanism of metal rectification equipment, into the atmosphere by a stack fan. It is related to the device.

The general structure of the ventilation mechanism in metal rectification equipment is to guide the dust-containing gas rising from the rectification tower to the rooftop through a stack, and then suck it into a stack fan through a dust collection bag, where it is purified. A method is adopted in which clean fan discharge air is dissipated into the atmosphere from an exhaust pipe.

However, if the fan stops operating and loses its dust collection ability, the inside of the factory will be immediately filled with harmful gas due to the ejection of harmful gas, which poses a great danger. Normally, multiple fans are installed, including backup fans, to ensure that all the fans do not stop working at once due to a malfunction.

In addition, as a countermeasure in the event of a power outage, private power generators are equipped as a backup power source, but in order to switch the fan's power source to the backup power source,
It takes about 2 minutes to consume, and in order to ensure safety during that time, a bypass stack is formed in the suction passage of the fan in a branched manner to bypass the bug with large flow path resistance, and the suction power of the fan is reduced. In the event of exhaustion, the gas rising from the equipment is vented directly to the atmosphere through a bypass stack.

As a passage switching valve for this purpose, a damper that opens in response to negative pressure is installed in the stack passage on the bag side, and the damper automatically closes when the negative pressure sucked by the fan disappears. On the other hand, a damper is installed in the passage of the bypass stack as a safety valve, and although this damper is normally closed, it can be opened manually in an emergency. .

However, according to the structure of such a conventional ventilation system, multiple locations (for example, 9
Because there are several locations where gas is generated, not only is it difficult to open and rotate each bypass stack in an emergency, but it is also unavoidable that a considerable amount of gas will be ejected into the room during these operations. As described above, there was a problem in that the operability and safety of the bypass stack were not sufficient.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a damper device for an exhaust bypass stack in which a damper is automatically opened in an emergency. It's about doing.

The present invention will be described below based on an illustrated embodiment.

As shown in FIGS. 1 to 3, the damper device of the embodiment includes a damper 2 horizontally suspended in the inner hole of a bypass stack 1, and an air cylinder vertically installed in a stationary part around the bypass stack 1. 3, an electromagnetic clutch 4 also mounted diagonally on the surrounding stationary part, and each limit switch arranged at four locations on the surrounding stationary part.
The main mechanical parts are formed by LU, LD, LR, LF and a baby air compressor (hereinafter referred to as "Bebicon") 5 installed at an appropriate location in the factory.
Further, the main electrical parts are formed by an energization control mechanism forming an electric circuit schematically shown in FIG. 2, and a step-down rectifier 6 and a battery 7 attached to the mechanism.

Thus, the bypass stack 1 is open to the atmosphere at its upper end, and its lower end is branched off from a main stack 8 that guides the rising dust-containing gas, and the main stack 8 is directly connected to the bypass stack 1. For example, the suction stack 9 branches horizontally, and the suction stack 9 further includes:
A negative pressure responsive damper 10 is interposed, and a dust collection bag 11, a stack fan 12, and a discharge pipe 13 are connected downstream of the stack 9.

In addition, in the steady operation state of the ventilation mechanism, as shown in the figure, the negative pressure responsive damper 10 is opened, and the bypass damper 2 is closed by automatic control.

By the way, the bypass damper (hereinafter simply referred to as a damper) 2 has a passive arm 14 pivotally attached to one protruding end of its rotation shaft 2a, and a swing arm 15 pivotally attached to the other protruding end. hand,
Further, at the tip of the passive arm 14, a pin 14a that faces the push plate 16 attached to the tip of the operating rod of the cylinder 3 is provided to protrude laterally, and at the tip of the swing arm 15, a shelf is provided. Plate-shaped magnetic piece 1
7 is fixed.

Therefore, when the damper 2 is in the closed position (shown in FIG. 2), the magnetic piece 17 hits the clutch 4, and the limit switch is activated at the middle part of the swing arm 15.
The LU is pushed up, and when the damper 2 is in the open position (see FIG. 4), the limit switch LD is pushed down at the middle part of the arm 15.

Next, the operating rod of the air cylinder 3 is urged back upward by the elasticity of an internal spring (not shown).
6 is retracted, and dynamic pressure air stored in the tank of Bebicon 5 is supplied to the working chamber of the cylinder 3 via the solenoid valve 18.
When the valve passage 8 is open, the dynamic pressure air flows into the operating chamber, causing the operating rod to protrude downward against the elasticity of the return spring, thereby pushing the push plate 16
pushes down the pin 14a of the passive arm 14, and if the damper 2 is open, drives the damper 2 to the closed position.

An actuating piece 16a made of a thick plate is fixed to one end of the push plate 16, and the actuating piece 16a drives the limit switches LR and LF, thereby retracting (LR) and protruding (LR) the actuating rod. LF) is detected by switches LR and LF.

In addition, the Bebicon 5 is supplied with AC power from a commercial power source or a privately generated power source, and the internal pressure of the stored air in the tank is always maintained at a constant pressure by the action of an attached pressure switch.

Next, we will discuss the energization control mechanism.
DC is used, and this power supply DC is a regular power supply.
AC is voltage-transformed and current-transformed by a step-down rectifier 6, and a storage battery 7 is connected to the power supply circuit in a floating manner. Even in this case, power is automatically supplied by discharging the storage battery 7.

Note that the circuits 20 and 21 of the regular power supply AC are not power supply circuits, that is, the power supply circuits 20 and 21 of the regular power supply AC are
and a signal source circuit for detecting a power outage, which is a timer relay circuit T1 for electromagnetic clutch 4, when the regular power supply AC is applied to the timer relay circuit _T1 , provided that LU is closed. is closed (ON), and in the event of a power outage of the AC power supply, a timer circuit is started and the relay circuit _T1 is opened (OFF) after 5 seconds.

In addition, the timer relay circuit T ₂ for the solenoid valve 18 is
It operates only when the power supply AC that has been out of power starts transmitting power. Specifically, it closes (ON) the relay circuit for a predetermined period of time (for example, 5 seconds) from the start of power transmission. ).

The operation may be a manual operation using a push button switch.

In addition, the timer relay circuit _T3 of the limit switch LF opens (turns OFF) the relay circuit of the timer relay circuit _T2 one second after the switch LU is turned on and the limit switch LF is turned on and the electromagnetic clutch is energized.

Manually operated switches S ₁ and S ₂ are emergency switches for on-site operations that are not normally used. In the normal position, switch S ₁ is operated to "ON" and switch S ₂ is operated to "OFF". It is in a state of being.

Next, the operation of the damper device of the embodiment configured as described above will be described.

In the state shown in Figures 1 to 3, in which the ventilation mechanism is operating normally, both circuit T ₁ and switch S ₁ are closed, so that the electromagnetic clutch 4 is connected to the power supply DC.
is energized and the damper 2 is electromagnetically held in the closed position, while the circuit T ₂ is continuously supplied with power AC and the circuit T ₂ is open, so the solenoid valve 18 is closed. side, the cylinder 3 is in the inactive return position, that is, the push plate 16 is in the passive arm 1
It is far from 4.

In this state, if the power supply AC fails and is not restored within 5 seconds, the circuit _T1 will open after 5 seconds, and the power to the clutch 4 will stop and the magnetic force will disappear, causing the damper 2 automatically assumes the open position (see Figure 4) due to its own weight.

Due to such an operation, the bypass damper 2 opens almost at the same time as the stack fan 12 is de-energized for 5 seconds or more and the suction force of the fan 12 disappears, thereby exhausting the dust-containing gas directly into the atmosphere. Therefore, dust-containing gas will not be blown into the room.

In addition, even if the power is cut off for a short time due to unstable contact in the power supply circuit, the damper 2 will not open, and therefore there is no risk of unnecessary confusion.

Next, when the power outage is restored or the switch to in-house power generation is completed and the commercial power supply AC is supplied again, circuit T ₂ is closed immediately after power supply, so
The solenoid valve 18 is energized for, for example, 5 seconds to open the valve circuit, which causes the cylinder 3 to operate and press the push plate 16.
drives the damper 2 to the closed position.

Further, the above operation may be performed manually using a push button switch.

When damper 2 closes, the limit switch
LU and LF start energizing the clutch 4 from the circuit _T1 , and as a result, the damper 2
is electromagnetically attracted to. For one second after the clutch is energized, power is transmitted twice from circuit _T3 to clutch 4, and damper 2
After one second, the solenoid valve ₁₈ closes the valve passage, and the cylinder 3 becomes inactive. It then returns to its habitual position. Furthermore, in the case of poor clutch suction, if the switch LU opens when the cylinder starts to return, an alarm is issued and the cylinder is operated again so that the damper 2 closes.

In this way, the damper 2 is reliably closed according to a predetermined sequence after the commercial power supply AC is resupplied.

Furthermore, each of the above-mentioned operations is performed using the storage battery 7 power supply, which is maintained during a power outage of the AC power supply, and the Bebicon 5 power supply.
Reliable operation is possible because it is powered by the stored air in the tank.

In addition, each limit switch LU, LD, LR, LF
When in operation, an indicator lamp (not shown) lights up, so it is possible to confirm the operating position of the damper 2 and cylinder 3 from the outside.If it is necessary to make manual corrections, you can press the operation button. By operating switches S ₁ and S ₂ , damper 2
can be opened or closed at any time.

Further, by forming a plurality of the above-mentioned energization control mechanisms in a composite manner, it is possible to easily control the ventilation mechanisms at many locations simultaneously.

In addition, in the configuration of the above-described embodiment, the cylinder 3 is operated in one direction by the return behavior of the elasticity, but instead of this, the cylinder 3 may be operated by co-dynamic pressure air in both directions. A computer circuit is used to configure the control mechanism.

As described above, according to the damper device for the exhaust bypass stack according to the present invention, under normal conditions, harmful gases pass from the main stack 8 to the suction stack 9, are interposed downstream of the suction stack 9, and are removed from the drive power source. In a device that discharges air by a stack fan 12 driven by the electric power of The electromagnetic clutch 4 that fixes the damper 2 is disconnected.
By setting the stack fan 12 to the open position by its own weight, the harmful gas is allowed to escape to the side of the bypass stack 1. Therefore, when the stack fan 12 stops due to a power outage, the harmful gas will be blown out into the indoor side of the factory etc. This has the effect of ensuring safety.

Furthermore, according to the present invention, the bypass damper, which has a tendency to open due to its own weight, is electromagnetically held when closed, and the damper in the open position is closed by an air cylinder driven by stored air dynamic pressure air. The system is configured to automatically release the electromagnetic hold with a delay in the event of a power outage, and to automatically operate the air cylinder when the power outage recovers, thereby reducing the suction force of the stack fan. It becomes possible to automatically open and close the bypass damper in response to extinction and recovery, and as a result, all operations of the ventilation mechanism to ensure safety are automated, and the operation is stabilized. is obtained, which gives
This has the effect of effectively achieving labor saving in the ventilation mechanism.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram of a dust-containing gas exhaust stack, Fig. 2 is a schematic diagram of a damper device of an exhaust bypass stack showing an embodiment of the present invention, and Fig. 3 shows the main parts of Fig. 3. The top view and FIG. 4 are operational diagrams of the main parts of FIG. 2. 1... Bypass stack, 2... Damper, 3... Air cylinder, 4... Clutch, 5... Baby air compressor, 6... Step-down rectifier, 7... Battery, 9... Suction tank, 12... Stack fan, 18... Solenoid valve.

Claims (1)

[Claims] 1. Harmful gas moving from the main stack 8 to the suction stack 9 is discharged to the discharge tube 13 side by a stack fan 12 which is interposed downstream of the suction stack 9 and is driven by electric power from a drive power source. ,
In a device in which a bypass stack 1 is branched off in the middle of the main stack 8, the bypass stack 1 is rotatably supported in the bypass stack 1 integrally with a rotary shaft 2a. A damper 2 for opening and closing the bypass stack 1 is provided, and a swing arm 15 is fixedly attached to a protruding portion of the rotary shaft 2a of the damper 2 to the outside of the bypass stack 1.
An electromagnetic clutch 4 is provided on the outer stationary part, and when the drive power source is energized, the clutch 4 is operated and the swing arm 15 is electromagnetically attracted to the clutch 4, thereby closing the damper 2. The exhaust bypass is characterized in that a clutch energization control means is formed in which the clutch 4 is disengaged after a predetermined delay time and the damper 2 is placed in the open position by its own weight when the drive power supply is out of power. Stack damper device. 2. The exhaust bypass stack according to claim 1, wherein a float battery is used as an operating power source for the clutch energization control means and the solenoid valve energization control means, and the rated capacity is maintained by constant charging. damper device. 3. The harmful gases moving from the main stack 8 to the suction stack 9 are discharged to the discharge tube 13 side by the stack fan 12, which is provided downstream of the suction stack 9 and driven by electric power from the drive power source.
In a device in which a bypass stack 1 is branched off in the middle of the main stack 8, the bypass stack 1 is rotatably supported in the bypass stack 1 integrally with a rotary shaft 2a. A damper 2 for opening and closing the bypass stack 1 is provided, and a swing arm 15 is fixedly attached to a protruding portion of the rotary shaft 2a of the damper 2 to the outside of the bypass stack 1.
An electromagnetic clutch 4 is provided on the outer stationary part, and when the drive power source is energized, the clutch 4 is operated and the swing arm 15 is electromagnetically attracted to the clutch 4, thereby closing the damper 2. position, and in the event of a power outage of the drive power source, the clutch 4 is disengaged after a predetermined delay time and the damper 2 is placed in the open position by its own weight. Dynamic pressure air is supplied from the baby air compressor 5 via the valve 18, and when the electromagnetic valve 18 is energized to the open side, the damper 2 is supplied via the passive arm 14 fixed to the protrusion of the rotating shaft 2a. an air cylinder 3 that is pushed and biased to the closed position by the air cylinder 3; and a damper 12 that is biased by the air cylinder 3 while energizing the solenoid valve 18 to the open side at the initial stage of energization of the drive power source;
a solenoid valve energization control means configured to stop the energization to the solenoid valve 18 after the closed position is set;
A damper device for an exhaust bypass stack, characterized in that: 4. The exhaust bypass stack according to claim 3, wherein a float battery is used as an operating power source for the clutch energization control means and the solenoid valve energization control means, and the rated capacity is maintained by constant charging. damper device.