JPH08145218A - Exhaust valve device for vacuum drainage collecting and discharging tank - Google Patents

Abstract

PURPOSE: To propose an exhaust valve device which closes an exhaust port while speedily making a butterfly valve contact with a valve seat so as to perfectly prevent entrance of drainage from an exhaust port to a vacuum pump in the case that trouble or time lag occurs at a level switch for detecting an upper limit of drainage and level of the drainage abruptly increases. CONSTITUTION: An exhaust valve device for vacuum drainage collection and discharge tank has a suction port to which a vacuum drainage pipe is connected, a discharge port to which a press-feed pipe communicated with a purifying facility, and an exhaust port communicated with a vacuum pump for suctioning drainage in the vacuum drainage pipe. In such an exhaust valve device, a butterfly valve 4 is provided on a flange 1 formed with a valve seat 2 projected downward, which butterfly valve 4 is fixed at its one end and performs opening/ closing of the exhaust port due to oscillation. A spherical float 9 is provided on a back surface of the butterfly valve 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exhaust valve device for a tank used in a vacuum type waste water collecting and draining device in drainage treatment of local municipalities and mountain villages.

[0002]

2. Description of the Related Art According to a vacuum sewer system, which has recently been attracting attention in local municipalities and mountain villages where sewage system maintenance is urgently required, domestic wastewater discharged from households flows into the wastewater basin under natural flow. The sewage is sent to the vacuum type sewage collection and drainage device through the vacuum sewer pipe. When a certain amount of sewage is accumulated in the tank, it is sent from the pressure pump to the purification plant via the pressure pipe. An exhaust port communicating with a vacuum pump for sucking dirty water in a vacuum sewer pipe is provided at the top of the tank of the vacuum type waste water collecting and draining device, and the exhaust port is provided with a butterfly valve v of the type shown in FIG. To prevent the infiltration of dirty water.

[0003]

When the level of the sewage in the tank increases and reaches the upper limit, the upper limit level switch detects this and the vacuum pump is stopped, and then a pressure pump such as a bladeless pump is started. Is configured to.
However, when the upper level switch causes trouble such as time lag due to dirt or scum, the water level rises rapidly, so the conventional butterfly valve causes an ejector phenomenon of the wastewater and the wastewater enters the vacuum pump side. There is a risk of doing it. It is an urgent task to solve this problem in the vacuum type waste water collection and drainage device which is currently in the trial stage.

Therefore, it is an object of the present invention to completely prevent sewage from entering the vacuum pump through the exhaust port when a trouble or time lag occurs in the level switch for detecting the upper limit of sewage and the sewage rises sharply. In order to prevent this, it is an object of the invention to propose an exhaust valve device in which the butterfly valve is quickly brought into contact with the valve seat to close the exhaust port.

[0005]

The present invention is provided with an intake port to which a vacuum sewer pipe is connected and an exhaust port to which a pressure feed pipe communicating with a purification treatment site is connected, and sucks dirty water in the vacuum sewer pipe. In the exhaust valve device of the vacuum type waste water collecting and draining tank having an exhaust port communicating with the vacuum pump, one end is fixed to a flange having a valve seat protruding downward to open and close the exhaust port by swinging. A butterfly valve is provided, and a spherical float is provided on the back surface of the butterfly valve.

[0006]

According to the exhaust valve device of the vacuum type waste water collecting and draining tank constructed as above, when the water level of the waste water in the tank increases and reaches the upper limit, it is normally a level switch for detecting the upper limit of the waste water. And the vacuum pump stops. At this time, the butterfly valve remains separated from the valve seat, and the exhaust port communicating with the vacuum pump is opened. Then, when the level of sewage increases and reaches the upper limit, and if there is a sudden rise in the level of sewage due to a trouble or time lag in the level switch, the butterfly valve uses a buoyancy effect of a spherical float to seat the valve. Since the exhaust port is closed by contacting the valve seat before the sewage reaches the sewage, the sewage does not flow into the vacuum pump side. Therefore, it is possible to avoid problems such as water lock caused by sucking dirty water into the vacuum pump. When the wastewater is sent to the purification plant side by the pressure pump and the water level begins to drop, the butterfly valve gradually separates from the valve seat and the exhaust port opens. When the level switch for detecting the lower limit of the dirty water operates, the pressure pump stops and the vacuum pump starts again to start sucking the dirty water in the vacuum sewer pipe into the tank.

[0007]

1 is a perspective view of an exhaust valve device, FIG. 2 is a vertical side view of the same, and FIG. 3 is a vertical side view of a vacuum type waste water collecting and draining device. 4 is an explanatory view for dividing the tank in the radial direction and showing the relationship between the change in water level and the inflow time.

In FIGS. 1 and 2, V is an exhaust valve device, and the exhaust valve device V is formed by projecting a valve seat 2 below a flange 1 and a through hole 3 is formed at the center of the valve seat 2. One end 5 of the butterfly valve 4 made of elastic material is fixed to the flange 1 with a screw 8. The butterfly valve 4 has a known structure in which the through hole 3 is opened and closed by contacting or separating from the valve seat 2 by swinging, and a strong canvas material is put in the bent portion 6 to reinforce it, and the core metal is inside. 7 may be buried. At the center of the back surface of the butterfly valve 4, a hollow spherical float 9 is fixed by a bolt 10.

Further, the butterfly valve 4 may be constructed such that a ring-shaped mounting portion surrounding the outer periphery of the valve seat 2 is integrally provided and the mounting portion is fixed to the flange 1.

FIG. 3 shows a vacuum type waste water collecting and draining device Z to which the exhaust valve device V of the present invention is applied. The vacuum type waste water collecting and draining device Z is provided with a cylindrical tank a for storing waste water, an intake port b to which a vacuum sewer pipe k is connected, provided above the tank a, and communicated with a purification treatment site below the intake port b. It has a discharge port c to which the pressure feeding pipe d is connected. An exhaust port f communicating with a vacuum pump p for sucking dirty water in the vacuum sewer pipe k is provided in the top e of the tank a, and the exhaust valve device V of the present invention is attached to the exhaust port f. There is. If the roots type multi-stage vacuum pump is a vacuum pump p, the motor output is 7.5 to 11K.
W of w is desirable, and a vacuum degree of about 700 mmHg is generated to suck air in the tank a. In order to alternately automatically operate the vacuum pump p and the pressure feed pump g, an upper limit level switch s ₁ and a lower limit level switch s ₂ for detecting the water level L of the sewage are installed in the tank a, and the detection signal thereof is a switch relay box. It is transmitted via h to the controller i of the motor that drives the pumps p and g.

However, according to the exhaust valve device V of the vacuum type waste water collecting and draining tank thus constructed, when the water level L of the waste water in the tank a increases and reaches the upper limit, it is turned on. Detected in ₁ , the vacuum pump p stops.
At this time, the butterfly valve 4 remains separated from the valve seat 2, and the through hole 3 communicating with the vacuum pump p is open. When the water level L of the dirty water increases and reaches the upper limit, if the trouble or time lag occurs in the level switch s ₁ and the water level of the dirty water suddenly rises, the butterfly valve 4
Since the buoyant force of the spherical float 9 contacts the valve seat 2 and blocks the through hole 3 before the dirty water reaches the valve seat 2, the dirty water does not flow into the vacuum pump p side. Therefore, it is possible to avoid problems such as a water lock that is caused when the dirty water is sucked into the vacuum pump p. When the wastewater is sent to the purification plant side by the pressure pump g and the water level L starts to drop, the butterfly valve 4 gradually separates from the valve seat 2 and the through hole 3 opens (in a normal state, the butterfly valve 4 has the valve seat It remains separate from 2.). When dirty water is discharged and the water level L decreases and the lower limit level switch s ₂ detects this, the pressure pump g is stopped, the vacuum pump p is restarted, and the vacuum sewer pipe k is started.
Start to suck the dirty water into the tank a.

Next, the relationship between the water level change in the tank and the inflow time will be considered. As shown in FIG. 4, the tank is divided into 10 in the radial direction, and the inflow time with respect to the water level change is calculated by the following mathematical formula.

[0013]

[Equation 1]

[0014]

[Equation 2]

[0015]

(Equation 3)

[0016]

[Equation 4]

[0017]

[Table 1]

In the above equation, r is the radius of the tank, C
Is the surface width of the divided water level, l is the outer peripheral length of the divided water level, n is each divided water level, A is the area of each divided water level, t is the inflow time of the waste water into the tank, L is the tank length, and Q is Indicates the inflow amount, where r = 1 m, L = 1.6 m, Q = 1 m ³ /
The value of min. As a result, in the above table, the water level will rise by 0.3 m in the remaining approximately 30 seconds when the sewage is near full, so the exhaust valve device must react to a sudden rise in water level and close the exhaust port. It is clear.

[0019]

The present invention has the above-described structure and operation, and the butterfly valve has an excellent effect of quickly contacting the valve seat and closing the through hole by the buoyancy of the spherical float. Moreover, in the vacuum type waste water collection and drainage device to which this exhaust valve device is applied, even if a trouble or a time lag occurs in the level switch that detects the upper limit of the waste water in the tank and the waste water level rises rapidly, It has a secondary effect that it can be completely prevented from entering the vacuum pump.

[Brief description of drawings]

FIG. 1 is a perspective view of an exhaust valve device.

FIG. 2 is a longitudinal side view of the same.

[Figure 3] Vertical side view of the vacuum type waste water collection and drainage device

FIG. 4 is an explanatory diagram showing a relationship between a change in water level and an inflow time by dividing a tank in a radial direction.

FIG. 5 is a vertical sectional side view of a conventional butterfly valve.

[Explanation of symbols]

L → Sewage water level V → Exhaust valve device Z → Empty type wastewater collection / drainage device a → Tank b → Suction port c → Drain port d → Pressure pipe e
→ Top part f → Exhaust port g → Pressure pump h → Switch relay box i → Control device k → Vacuum sewer pipe p → Vacuum pump s ₁ → Upper level switch s ₂ → Lower level switch 1 → Flange 2 → Valve seat 3 → Through hole 4 → Butterfly valve 5 → One end 6 → Bend 7 → Core 8 → Screw 9 → Spherical float
10 → bolt

Claims (1)

[Claims] 1. An exhaust port having a suction port to which a vacuum sewer pipe is connected and a discharge port to which a pressure feed pipe communicating with a purification treatment site is connected, and an exhaust port communicating with a vacuum pump for sucking dirty water in the vacuum sewer pipe. In the exhaust valve device for a vacuum type waste water collecting and draining tank, the butterfly valve having a valve seat protruding downward is provided with a butterfly valve whose one end is fixed to open and close the exhaust port by swinging the butterfly valve. An exhaust valve device for a vacuum type waste water collection and drainage tank, characterized in that a spherical float is provided on the back surface of the.