JPH0714231Y2 - Storage tank - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a storage tank for storing a liquid, particularly a highly viscous fluid, and stably supplying the liquid to a subsequent process.

[Conventional technology and problems to be solved]

After polymerizing various plastic raw materials or blending the materials in a certain ratio, in order to continuously mold resin molded products with a molding machine, a plurality of reaction devices, mixing devices, etc. are installed, The molten resin must be stably supplied to the molding machine. However, increasing the number of reactors, mixing devices, etc. installed for stable resin supply increases the manufacturing cost. Therefore, a storage tank (intermediate tank) that temporarily stores the resin is provided between the reaction device and the molding machine, and the resin is stably supplied from the storage tank to the molding machine. It is being reduced.

As shown in FIG. 5, the resin 3 is poured into one of the storage tanks from an inlet 2 provided at an upper portion of a vertically-arranged cylindrical storage tank 1 and stored in the storage tank 1. There is provided one in which the resin 3 is made to flow out from an outlet 4 provided in the lower portion thereof and supplied to a molding machine.

However, since this storage tank 1 drops the resin 3 from the inflow port 2 provided in the upper part to the lower part in the storage tank 1, air is entrained in the middle of the resin, or the resin 3 is vigorously dropped to the liquid surface. There was a problem that bubbles were generated.

Therefore, the pressure inside the storage tank 1 is reduced to evacuate the resin 3. However, when the viscosity of the resin 3 is high, the resin 3 cannot be easily degassed, and further, by reducing the pressure, the resin 3 is sucked from the inflow port 2 and vigorously flows in, while the suction force is also applied to the outflow port 4. There was a new problem that the load acting on the pump increased due to work.

As a solution to such problems, a storage tank 5 as shown in FIG. 6 is provided. This storage tank 5 is provided with an inflow port 2 for the resin 3 in the lower part of the tank which is in the immediate vicinity of the outflow port 4, and normally stores the resin 3
Is designed to flow in.

However, in this storage tank 5, the resin 3 that has flowed in from the inflow port 2 flows along the shortest path to the outflow port 4 as indicated by the arrow in the figure, so that the resin 3 that has flowed in later will come first. The resin 3 stored above the inflow port 2 hardly stagnates and flows out.
For this reason, the resin 3 retained in the storage tank 5 for a long period of time may be deteriorated by oxidation or the like, which is a problem from the viewpoint of maintaining the quality of the resin molded product. In particular, when such a storage tank 5 is used for manufacturing food products, it is a big problem.

[Means for solving problems]

The present invention has been made to solve such problems, and the gist of the storage tank according to the present invention is to incline the floor of the tank main body and In the vicinity of both ends in the inclination direction, an inlet for letting the fluid into the tank body and an outlet for letting out the introduced fluid to the outside of the tank body are located at the position of the outlet. It is arranged so as to be higher, and either or both of the inflow port and the outflow port are formed in a shape in which the diameter is increased as it goes to the opening end opening inside the tank body.

Further, in the storage tank, the pressure inside the tank body is increased.

[Action]

According to the present invention, the floor of the tank body is slanted, and the inflow port is disposed at the upper part and the outflow port is disposed at the lower part in the vicinity of both ends in the slanting direction of the slanted floor part. , The fluid introduced from the inlet provided at the upper part of the floor flows along the floor to the outlet on the downstream side without gradually entraining the gas, and the fluid gradually accumulates from the downstream side. And then stored. After the liquid surface of the fluid stored in the tank covers the floor (inlet), the fluid is allowed to flow into the solution of the fluid from the inlet.
The fluid stored in this way flows out from the outlet provided in the lower part on the downstream side of the floor and is supplied to the next step. The fluid supplied to the tank flows along the inclined floor portion from the inflow port to the outflow port, and is discharged from the outflow port without staying. Next, when the supply of the fluid to the tank is stopped and all the fluid in the tank body is discharged, the stored fluid is discharged along the inclined floor portion at a substantially constant speed at the outlet on the downstream side. All of it is discharged without flowing into the inside and staying inside.

Further, in the storage tank of the present invention, the shape of the inflow port is such that the diameter increases as it goes to the opening end inside the tank, and the flow rate of the supplied fluid is reduced at the inflow port. Therefore, the fluid is slowly flown into the tank body and does not entrain gas. On the other hand, the shape of the outflow port also has a shape that expands in diameter as it goes to the opening end, and when the fluid stored in the tank body is discharged from the outflow port, The average flow velocity is reduced and eddies are prevented from occurring. Therefore, gas entrapment due to the generation of vortices is prevented.

In addition, in the storage tank of the present invention, the fluid inside the tank body may be pressurized by a compressor or the like to force the fluid to be pumped to the inlet of a pump for letting the fluid out from the outlet. Therefore,
When the fluid is a highly viscous substance, if it is not pressurized or the internal pressure is insufficient, the inlet side of the outflow pump becomes a vacuum and the pump feed amount becomes insufficient or becomes unstable. Does not generate bubbles due to vapor pressure and entrain them in the fluid. Also, when the pipe on the inlet side descends from a high place, when the valve installed at the high place is stopped and the supply of fluid is stopped, the inside of the pipe on the outlet side of the valve becomes negative pressure and vapor pressure Due to bubbles,
It is possible to prevent air from entering.

〔Example〕

Next, an embodiment of the storage tank according to the present invention will be described in detail with reference to the drawings.

In FIG. 1, reference numeral 10 is a storage tank having a closed structure. The storage tank 10 includes a tank main body 12 having a cylindrical side surface, and a cylindrical side surface of the tank main body 12 inclined with respect to the horizontal direction. It is composed of support members 16 and 18 which are supported on the base 14. The storage tank 10 has a bottom portion, which is a part of the cylindrical side surface of the tank body 12, as a floor portion 20,
The floor 20 is installed so as to be tilted by tilting 12. The floor portion 20 of the tank body 12 is provided with an inlet 24 for allowing the resin 22 to flow into the storage tank 10 on the upper side of the inclined floor portion 20, and on the lower side of the floor portion 20. An outlet 26 is provided for letting out the stored resin 22 to the outside of the storage tank 10.

The inflow port 24 is, as shown in FIG.
It is formed in a conical shape in which the inner diameter is increased as it goes from the external connection portion 28 side to the internal opening portion 30 side. This is to prevent the resin 22 from being jetted into the storage tank 10 by gradually reducing the flow velocity at the inflow port 24 in which the resin 22 that has been vigorously sent from the reaction device or the like is expanded. This prevents the generation of bubbles.

On the other hand, as shown in FIG.
Like the inflow port 24, the inflow port 24 is also formed in a conical shape whose inner diameter is enlarged as it goes to the opening 31 inside the tank body 12. This is the resin drawn by a pump not shown
22 so as not to forcefully flow out from the outlet 26 and generate a vortex in the resin solution stored inside the tank body 12,
This is for reducing the average flow velocity of the resin 22 flowing toward the outflow port 26, which prevents the generation of vortices and thus prevents the gas from being entrained in the resin 22.

Further, the pressure inside the tank main body 12 is to send compressed air that has been pressure-fed from a compressor (not shown) into the tank main body 12 from an air supply port 32 provided at the upper part of the tank main body 12,
Pressurized. By increasing the internal pressure of the tank body 12, the resin 22 is pressure-fed to the inlet of a pump (not shown) for causing the resin 22 to flow out from the outlet 26. When the resin 22 is a highly viscous material, if it is not pressurized or the internal pressure is insufficient, the inlet side of the outflow pump becomes a vacuum, and the pump feed amount becomes insufficient or becomes unstable. Is sufficiently pressurized because bubbles are generated by the vapor pressure and are entrained in the resin 22. In addition, the inflow port 24
When the pipe on the side of the pipe descends from a high place, when the valve installed at the high place is stopped and the supply of resin 22 is stopped, the inside of the pipe on the outlet side of the valve becomes negative pressure and bubbles are generated due to vapor pressure. When the next resin 22 is supplied, resin 22
Gas may be trapped inside. Therefore, the inside of the tank body 12 is pressurized to prevent the inside of the pipe from becoming negative pressure.

In the storage tank 10 having such a configuration, the resin 22 sent from the reaction device or the like is made to flow into the tank body 12 at a slow speed by reducing the flow velocity at the inflow port 24. The resin 22 that has flowed into the tank body 12 (two-dot chain line in the figure) gradually flows over the inclined floor portion 20 toward the downstream outlet 26, and gradually accumulates from the outlet 26 side. The liquid level of the resin 22 thus stored rises. After the liquid surface of the resin 22 exceeds the opening 30 of the inflow port 24 (indicated by a dashed line in the figure), the resin
The resin 22 is allowed to flow into the solution of 22 through the inflow port 24. On the other hand, when the stored resin 22 is caused to flow out from the outlet 26, no vortex is generated at the outlet 26, and there is no place where the resin 22 stays in the flow of the resin 22 in the tank body 12, and the resin 22 is It can be smoothly discharged from the outlet 26 in order. Further, even if the resin 22 is a highly viscous material, the pressure inside the tank body 12 makes it possible to stably supply a constant amount of the resin 22 by a pump without entraining bubbles.

As is clear from the above description, in any process, air is not entrained in the resin 22 to generate air bubbles, and without forming a step such as deaeration, the resin molding having excellent quality is immediately performed in the next step. It becomes possible to mold the product. Further, since the stored resin 22 flows out from the storage tank 10 in order and is made to flow out, and there is no place where it is retained in the storage tank 10, the situation in which the resin 22 deteriorates in the storage tank 10 does not occur. Further, even when the use of the storage tank 10 is stopped, since the floor portion 20 is inclined, all the stored resin 22 flows out from the outflow port 26, which is economical.

Although one embodiment of the storage tank according to the present invention has been described above in detail, the present invention is not limited to the above-described embodiment, and can be implemented in other forms.

For example, as shown in FIG. 3, the inlet 34 of the storage tank 10
The diameter may be increased in a curved shape as it goes from the connecting portion 36 to the opening 38. The shapes of the inlets 24 and 34 are preferably set so that the velocity of the fluid at the opening is as slow as possible in consideration of the flow velocity and pressure of the fluid such as the resin to be sent. .

It should be noted that the outflow port can also have the same configuration as this example, and the inflow port and the outflow port are not limited to these examples. The shapes of the inflow port and the outflow port can be appropriately set, and it is not necessary to use the same shape for both.

Further, the shape of the tank main body 40 is not limited to a cylindrical shape, and may be, for example, a tubular structure having a triangular cross section as shown in FIG. It is also possible to do so. The shape of the tank body is
The floor may have any shape as long as it is inclined, and is not limited in any way.

Furthermore, it is desirable that the inclination angle of the floor of the tank body is appropriately set according to the viscosity of the fluid, and if the viscosity of the fluid is high, the inclination angle of the floor is set large so that the fluid is If the fluid is made to flow upwards and the viscosity of the fluid is low, on the contrary, the inclination angle of the floor is set small so that the fluid does not easily flow on the floor. That is, the inclination angle of the floor is set so that the fluid flows slowly along the floor surface without entraining air.

In addition, the storage tank according to the present invention can be used not only for resin but also for fluids such as chemicals and foods, and even if the inlet is of a type that does not normally expand the diameter, it has some effect. Further, pressurizing the inside of the tank body is not an indispensable requirement, depressurizing may be atmospheric pressure, and the position of the inlet may be provided slightly downstream, etc. The invention is within the scope of the idea,
It is possible to carry out the embodiment in which various variations, improvements and modifications are made based on the knowledge of those skilled in the art.

[Effect of device]

According to the present invention, a fluid such as a resin, which is made to flow at a slow rate from an inlet provided on an inclined floor of the tank body, slowly flows through the floor to an outlet on the downstream side. Since the air is not stored in the fluid, air bubbles do not enter the fluid, and the molding process can be immediately performed in the next step without performing deaeration or the like. Moreover, since the fluid stored in the storage tank is discharged from the outlet in order without being retained, the fluid is not deteriorated in the tank due to oxidation or the like. Has an excellent effect.

[Brief description of drawings]

1 is a front sectional view showing an embodiment of a storage tank according to the present invention, and FIG. 2 is an enlarged sectional view showing an inlet (outlet) of the storage tank shown in FIG. FIG. 3 is a sectional view showing another embodiment of the inlet of the storage tank according to the present invention, and FIG. 4 is a side sectional end view showing another embodiment of the tank body of the storage tank according to the present invention. is there. FIG. 5 is an explanatory view showing a conventional storage tank, and FIG. 6 is an explanatory view showing another conventional storage tank. 10; storage tank 12,40; tank body 20; floor 24, 34; inlet 26; outlet 30,38; opening

Claims (2)

[Scope of utility model registration request] 1. A floor of a tank main body is tilted, and an inlet for introducing a fluid into the tank main body and a flowed inflow are provided in the vicinity of both ends of the tilted floor in the tilting direction. The outlet for letting the body flow out of the tank main body is arranged such that the position of the inlet is higher than the position of the outlet, and the shape of either or both of the inlet and the outlet is defined by the tank main body. A storage tank having a shape in which the diameter is increased as it goes to the opening end that opens inside the container. 2. The storage tank according to claim 1, wherein the pressure inside the tank body is increased.