JPH0246475B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an improvement in a vent filter provided in a tank or the like for storing or transporting liquid raw materials such as foods, drugs, cosmetics, etc.

Conventional technology Tanks used to temporarily store or transport liquid raw materials in the food industry, pharmaceutical industry, cosmetics industry, chemical manufacturing industry, etc., have pressure differences caused by changes in the internal liquid volume. As shown in Figure 4, a vent filter is installed to supply outside air into the tank and to exclude air inside the tank.

However, if both air supply and exhaust are carried out through a vent filter as in the past, if the temperature of the liquid in the tank is high or if the tank is cleaned with steam, moisture may accumulate on the filtration surface of the vent filter. There is a defect in which the filtration function deteriorates due to adhesion of steam.To prevent this, the filter material must be removed, or a special mechanism such as a three-way valve installed between the tank and vent filter to prevent steam from flowing into the filter material must be added. The reality is that both methods are troublesome to operate, and the latter has drawbacks such as a complicated configuration.

Problems to be Solved by the Invention In view of these current circumstances, the present invention has been developed to eliminate the need for troublesome operations or expensive and complicated additional equipment, and to use a slight differential pressure within the tank to allow air to flow through the tank without passing through a filter tube. The purpose of this is to protect the filtration surface from the moisture by evacuating the air, thereby preventing the filtration function from deteriorating.

Means for Solving the Problems The present invention provides, as a means for achieving the above-mentioned object, a filter cylinder having a filter protruding from a tank, and a filter cylinder installed between the filter cylinder and the tank where the pressure becomes higher than that in the tank. The gist is that an intake valve is opened to communicate the filter cylinder and the tank, and an exhaust valve is opened to communicate the tank to the atmosphere when the pressure inside the tank becomes higher than the atmosphere.

Function: When the pressure inside the tank decreases due to a decrease in the amount of liquid in the tank, the outside air filtered by the filter cylinder opens the intake valve and is introduced into the tank, and as the amount of liquid in the tank increases. When the pressure inside the tank becomes high, the air inside the tank is directly discharged outside the tank from the exhaust valve without passing through the filter cylinder, and the air is discharged directly to the outside of the tank from the exhaust valve, especially when the liquid in the tank is high or when cleaning the tank with steam. This prevents the filter of the filter cylinder from getting wet and reducing the filtration performance.

Embodiment To explain an embodiment of the present invention with reference to the drawings, a filter cylinder 3 having a dustproof cover 2 is provided in the upper part of the tank 1, and filters 4, 4' are arranged on the circumferential surface of the filter cylinder 3 as is known in the art. is installed.

Further, between the tank 1 and the filter cylinder 3, there is a bottomed inner cylinder 6 whose upper end communicates with the filter cylinder 3 and has an intake hole 5 on the circumferential surface, and a bottomed inner cylinder 6 whose lower end communicates with the tank 1 and exhausts air to the circumferential surface. An outer cylinder 8 having a hole 7 is disposed in an overlapping state, and an intake valve 9 and an exhaust valve 10 are provided outside the intake hole 5 and the exhaust hole 7, respectively, and are openable to the outside.
Further, a cover 11 is provided on the outside of the outer cylinder 8.

Since the present invention is constructed as described above, when the pressure inside the tank 1 becomes low due to the pressure difference between the atmospheric pressure and the pressure inside the tank, the air flows to the filter tube 3 as shown by the solid line in FIG.
air is supplied into the tank 1 through the inner cylinder 6, intake valve 9, and outer cylinder 8, and when the pressure inside the tank 1 becomes high, the air in the tank 1 is supplied to the outer cylinder 8 as shown by the chain line in FIG.
The vapor in the tank 1 is therefore not attached to the filters 4, 4', wetting them and impairing the filtering function.

In the embodiment shown in FIGS. 2 and 3, an inner cylinder 6 is provided between the filter cylinder 3 and the tank 1, the upper end of which is connected to the filter cylinder 3, and the connecting part has an intake valve 9 that can be opened downward. and an outer cylinder 8 whose lower end communicates with the tank 1 and whose upper part is formed to have a larger diameter than the inner cylinder 6, and furthermore, the upper peripheral edge of the outer cylinder 8 on the outside of the inner cylinder is openable to the outside. The air supply function is performed through the filter tube 3 and the intake valve 9, and the exhaust function is performed directly from the tank 1 through the exhaust valve 10.

Effects of the Invention The present invention provides an intake valve that sucks atmospheric air into the tank through the filter cylinder and an exhaust valve that discharges the air inside the tank directly to the outside of the tank between the filter cylinder and the inside of the tank. The intake and exhaust valves are automatically activated by the pressure difference between atmospheric pressure and the tank internal pressure, allowing only the supply air to be introduced through the filter tube, and the tank air to be discharged directly from the tank without passing through the filter tube. Therefore, even if the stored liquid in the tank is at a high temperature or the tank is steam-washed, the filter material in the filter tube will not be wetted by the steam and the filtration function will not be deteriorated, making it inexpensive and simple. The structure has an excellent feature that can reliably protect the filtration cylinder of a vent filter such as a storage tank.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway front view of the present invention, Fig. 2 is a plan view of the main part of another embodiment of the present invention, Fig. 3 is a partially cutaway front view of the same, and Fig. 4 is a partially cutaway view of the conventional method. It is a front view. 1...Tank, 3...Filter cylinder, 4, 4'...Filter, 9...Intake valve, 10...Exhaust valve.

Claims (1)

[Claims] 1. A filter cylinder having a filter is provided protruding from the tank, and an intake valve is provided between the filter cylinder and the tank, which opens when the pressure in the filter cylinder becomes higher than that in the tank, allowing the filter cylinder and the tank to communicate with each other. A vent filter for a storage tank, etc., characterized in that it is provided with an exhaust valve that opens when the pressure becomes high and allows the tank to communicate with the atmosphere.