JPH0123527Y2 - - Google Patents

Description

[Detailed explanation of the invention] A. Purpose of the invention: ``Industrial application field'' This invention relates to a vacuum filter, and includes a filtration device using a filter medium, an automatic paper feeding device using a so-called automatic filter, and a machine tool. It can be applied to sewage treatment and other various industrial sectors.

``Prior Art'' Conventionally, for example, the ``vacuum filter'' disclosed in Japanese Patent Application Laid-open No. 17811-1983 has been proposed as a device that automatically supplies and discharges filter media and uses vacuum suction to filter and discharge cleaning liquid. However, this device has the following defects.

``Problems that the invention attempts to solve'' (1) It is inefficient because filtration work is performed intermittently.

(2) The vacuum tank immediately after filtration is large and the sewage inlet is high. Therefore, if the discharge port of machine tools or the like is low, it is necessary to pump up the dirty liquid and supply it to the vacuum filter.

(3) Since the size of the vacuum tank is limited, the processing flow rate is also limited and it is difficult to increase this.

(4) Conventionally, when draining the cleaning liquid accumulated in the vacuum tank, pressurized discharge was used to discharge the cleaning liquid quickly, but because there was no check valve, the filter medium was suddenly lifted up, causing a cake-like formation due to sludge on the filter medium. , and the cake effect during filtration was impaired.

B. Composition of the invention ``Means for solving the problems'' In order to eliminate the defects of the above-mentioned conventional method, the present invention
By installing a separation tank separate from the vacuum tank and connecting the two with a check valve, continuous automatic operation can be performed smoothly, and other drawbacks mentioned above have been eliminated.

"action" (1) Continuous automatic operation of filtration work can be performed smoothly.

(2) It is possible to reduce the size of the vacuum tank immediately after filtration, which lowers the inlet, eliminates the need for a supply pump, and enables inexpensive supply.

(3) It becomes possible to freely enlarge the vacuum chamber, increasing the throughput.

(4) By installing a check valve, it is possible to pressurize the drain at all times during continuous operation, making it possible to raise the drain port even without a drain pump, making it flexible to the height of the existing tank. This means that it will be possible to respond to Furthermore, the destruction of the cake-like deposited layer, which was the case with the conventional method, was eliminated.

``Example'' The principle of the vacuum filtration machine of the present invention will be explained with reference to FIG.
is installed, and the upper part of the vacuum tank 1 in contact with the filter medium is a perforated plate 2. The vacuum tank 1 is connected to further separation tanks 5, 6 through check valves 7, 8.

Initially tanks 1, 5, 6 have check valves 7, 8, 9, 1
Since the tank 3 is open to the atmosphere, when the dirty liquid flows into the tank 3, it is filtered through the filter material 4 due to its own weight, and the clean liquid falls into the vacuum tank 1, but it does not fall naturally. Since the amount of filtration is small, when the liquid level in the tank 3 rises, the level meter 17 detects the preset level and automatically opens the solenoid valve 13, and the ejector 11 removes the liquid from the separation tank 5. Then, the vacuum tank 1 is brought into a vacuum state and forced filtration is performed.

At this time, the vacuum tank 1 and the separation tank 5 are isolated from the atmosphere by check valves 9 and 10 to maintain a vacuum state. However, the separation tank 6 has a level switch 18.
In response to this signal, the pressurized air is shut off by the solenoid valve 14 and the air is opened to the atmosphere. When the tanks 5 and 1 are in a vacuum state, the dirty liquid in the dirty liquid inlet tank 3 is rapidly filtered by the filter medium 4, and the clean liquid flows into the vacuum tank 1 and the separation tank 5. When the vacuum condition continues and the cleaning liquid in the separation tank 5 fills up, the level switch 15
A preset level is detected and the electromagnetic switching valve 12 is automatically operated to switch the air circuit. Due to the switched air circuit, separation tank 5
The circuit that was connected to the ejector is now conversely connected to the pressure circuit that passed through the solenoid valves 13 and 14, and the separation tank 5 becomes pressurized, and the cleaning liquid that was filled inside is passed through the check valve 9. is discharged to the outside through. At the same time, on the other hand, the separation tank 6 is brought into a vacuum state by the circuit switched by the electromagnetic switching valve 12, and the cleaning liquid that has passed through the tank 1 continues to flow into the tank 6. A level switch 16 provided in the separation tank 5 detects the completion of discharging the liquid in the tank 5, and automatically switches the electromagnetic switching valve 12 to its initial state. At this time, the solenoid valve 14 remains open and the cleaning liquid contained in the separation tank 6 is pressurized and discharged until the draining is completed and the level switch 19 is turned on. The discharge of the liquid in the separation tank 5 and the inflow of the cleaning liquid into the separation tank 6 start at the same time, but due to the resistance of the filter medium 4, the time for the liquid to fill in the tank 6 and the flow of the cleaning liquid in the tank 5 are delayed. The time required to drain the liquid from the tank 5 is shorter than the time required to drain the liquid from the tank 5. Therefore, the liquid in the tank 6 will not overflow.

As described above, filtration and cleaning fluid discharge are performed automatically and continuously, but as time passes, filtered solids accumulate on the filter media, clogging the filter media and slowing down the filtration speed. When the liquid level in the dirty liquid inflow tank 3 rises and the level meter 17 detects this, the supply air pressure circuit is automatically shut off by the solenoid valve 13. When the supply air pressure circuit is interrupted, all vacuum suction and pressurization operations are discontinued.

At this time, the vacuum suction inside tank 1 is stopped, but because the tank is small, it is always full of cleaning fluid, and when the vacuum suction is stopped, there is no air space. , and check valves 7 and 9
Therefore, there is no negative pressure. Furthermore, even if some air space exists, since the volume is small, it passes through the filter cloth and is rapidly released from the negative pressure. Therefore, the filter cloth is the perforated plate 2
The filter cloth is immediately released from the stuck state, and the filter cloth can be moved easily.

In this state, the filter cloth 4 is wound up, a new filter cloth surface is installed on the filtration surface, and the old filter cloth on which solid matter has accumulated is turned out and discharged to the outside.

These filter cloth operations are automatically performed by a preset sequence circuit timer, etc., and when the settings are completed, the previously stopped solenoid valve 13 is returned to its original state, and the vacuum suction filtration operation is resumed. I can continue.

C. Effect of the idea The effects obtained by the present invention are as follows.

(1) Continuous automatic operation of filtration work can be performed smoothly.

(2) The vacuum tank can be made smaller,
Since no pump is required, the price can be lowered.

(3) The vacuum chamber can be enlarged freely, increasing the throughput.

(4) There is no reduction in filtration effectiveness due to destruction of the cake-like sediment layer.

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram showing one example of implementing the present invention. The symbols in the drawings indicate the following members, respectively. 1: Vacuum tank, 2: Perforated plate, 3: Sewage inflow tank,
4: Filter medium, 5: Separation tank, 6: Separation tank,
7: Check valve, 8: Check valve, 9: Check valve, 10: Check valve, 11: Air ejector, 12: Solenoid switching valve, 13: Solenoid valve, 14: Solenoid valve, 15: Level switch, 16: Level switch, 17: Level meter, 18: Level switch, 19: Level switch.

Claims (1)

[Scope of Claim for Utility Model Registration] 1. A sewage inflow tank with the upper part open to the atmosphere and the lower part open is placed on top, a vacuum tank with a perforated plate on the top is placed below, and a filter material is sandwiched between the two. A vacuum filter comprising another separation tank connected in series to the vacuum tank via a check valve. 2. The vacuum filtration machine according to claim 1, which is provided with two or more separation tanks. 3 The two separation tanks are provided, and each separation tank has a built-in upper and lower level switch, the lower part of which is connected to the vacuum tank and the atmosphere via a check valve, and the upper part of which is connected to the atmosphere via an electromagnetic switching valve. The vacuum filtration machine according to claim 1, which is connected to a solenoid valve for opening and closing pressurized air and an air ejector.