JP7746046B2 - Defoaming device - Google Patents

Description

The present invention relates to a defoamer that destroys and eliminates foam by suctioning it, and in particular to a defoamer that can effectively eliminate foam that forms on the surface of liquid stored in a liquid tank.

In conventional defoaming devices, bubbles that form on the liquid surface of a liquid tank are sucked in by the rotation of a rotor (impeller), and these bubbles are then transported to the outer periphery of the rotor by centrifugal action, where they are destroyed by shear stress from multiple defoaming walls attached to the outer periphery of the rotor (see, for example, Patent Document 1).

JP 2010-22992 A

However, with such conventional defoaming devices, the main body base is directly attached to the liquid tank that stores the liquid, so if the liquid tank is small, there is not enough space to install it, making it impossible to install.

The objective of this invention is to provide a defoaming device that can be installed even in small liquid tanks.

In order to achieve this object, the present invention takes the following measures:
the casing has an impeller having a plurality of blades extending radially from the center; a casing that houses the impeller inside and has a plate-like base plate attached to it; an inlet formed through the base plate on the front side of the casing facing the impeller so as to open toward the center of the impeller; an inner wall portion of the casing on the outer periphery of the impeller against which bubbles that are transferred from the inlet to the outer periphery of the impeller by centrifugal force due to the centrifugal action of the impeller collide so as to be destroyed; a storage tank that stores liquid resulting from the bubbles colliding with the inner wall portion of the casing ; a main body that is composed of an electric motor that drives the impeller to rotate from behind the casing ; and leg members that fix the main body to the liquid tank so as to be spaced vertically above the liquid tank , a cylindrical member having a suction flow path attached to the base plate of the casing, the suction flow path of the cylindrical member being connected to the inlet, and the cylindrical member having a suction port opening at the tip of the suction flow path that is positioned to face bubbles that form on the liquid surface of the liquid tank.

In this case, a discharge flow path may be provided connecting the storage tank and the liquid tank. The cylindrical member may be attached to the casing at an angle to the vertical direction. The cylindrical member may be configured so that the length between the inlet and the suction port is adjustable.

As described above in detail, the invention of claim 1 comprises an impeller, a casing for mounting a plate-like base plate , a main body comprising an inlet formed through the base plate , an inner wall portion, a storage tank, and an electric motor , and leg members for fixing the main body to the liquid tank so that the main body is positioned vertically above the liquid tank at a distance, a cylindrical member having a suction flow path attached to the base plate of the casing , the suction flow path of the cylindrical member being connected to the inlet, and a suction port opening at the tip of the suction flow path of the cylindrical member being positioned opposite bubbles that form on the liquid surface of the liquid tank. Therefore, there is no need to mount the main body on the liquid tank, and a defoaming device can be mounted even on a small liquid tank.

The invention described in claim 2 also provides a discharge flow path connecting the storage tank and the liquid tank. This allows the liquid resulting from the disappearance of bubbles to be efficiently returned to the liquid tank.

In the invention described in claim 3 , the cylindrical member is attached to the casing at an angle to the vertical direction. This allows the casing to be installed by shifting it horizontally from above the vertical direction of the liquid tank, which makes it possible to install the liquid tank even if there is an obstacle above it, thereby increasing the degree of freedom in installation.

In addition, the invention described in claim 4 allows the length between the inlet and the suction port of the cylindrical member to be adjusted. This allows the suction port to be set to the optimal position depending on the liquid level in the liquid tank, making it applicable to a wide range of applications.

1 is a vertical cross-sectional view of a defoaming device according to an embodiment of the present invention. FIG. 10 is a vertical cross-sectional view of a defoaming device according to another embodiment. FIG. 10 is a vertical cross-sectional view of a defoaming device according to still another embodiment.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
In Figure 1, reference numeral 1 denotes a liquid tank for collecting and storing liquid such as coolant, which is installed on the ground D. Reference numeral 2 denotes a defoaming device, whose main body 3 is disposed vertically (up and down on the page) above the liquid tank 1 at a distance. Reference numerals 4A and 4B denote two roughly U-shaped leg members of the defoaming device 2, and the main body 3 is fixed to the top plate 1A of the liquid tank 1. The main body 3 is composed of an impeller 5, a casing 6, an inlet 7, an inner wall portion 6A of the casing 6, a storage tank 8, an electric motor 9, etc. The impeller 5 has multiple blades 5B attached to the front side of a circular disk 5A so as to extend radially from the center, and an input shaft 5C attached to the radial center. The outer periphery of the impeller 5, i.e., the radially outer ends of each blade 5B, are disposed opposite the inner wall portion 6A of the casing 6. The input shaft 5C passes through the casing 6 and protrudes to the rear thereof, and is attached to an output shaft (not shown) of the electric motor 9.

The electric motor 9 is detachably attached to a mounting plate 10 with multiple bolt members 11. The mounting plate 10 has a casing 6 attached to its lower part by welding via multiple bosses 12. The casing 6 is approximately cylindrical, closed at the top and open at the bottom, and houses the impeller 5 inside. A disk-shaped base plate 14, a storage tank 8, and leg members 4A and 4B are attached to the lower part of the casing 6 with multiple collar members 13 and gaps between them, and multiple bolt members 15 are used. The inlet 7 is approximately circular and extends through the radial center of the base plate 14 toward the center of the impeller 5 on the front side of the casing 6 facing the impeller 5. A cylindrical member 16 is attached to the top surface of the base plate 14 by welding, and a substantially circular plate-shaped member 17 is attached to its upper end by welding, facing the blade 5B on the front side of the impeller 5. A second inlet 18 is formed in the plate-shaped member 17, concentric with the inlet 7 and having approximately the same diameter as the inlet 7.

A first cylindrical member 19 is welded to the underside of the substrate 14, and a second cylindrical member 20 made of a flexible material is elastically fitted tightly around the first cylindrical member 19. Each cylindrical member 19, 20 extends through the top plate 1A of the liquid tank 1 and into the interior of the liquid tank 1. A first suction flow path 19A connecting to the inlet 7 is formed in the first cylindrical member 19, and a second suction flow path 20A connecting to the first suction flow path 19A is formed in the second cylindrical member 20. A suction port 21 is opened at the tip of the second suction flow path 20A, and the suction port 21 is positioned opposite bubbles C generated on the liquid surface T of the liquid tank 1. The vertical fitting dimension of the second cylindrical member 20 fitted onto the first cylindrical member 19 can be adjusted, and the length between the inlet 7 and the suction port 21 can be adjusted by adjusting the fitting dimension. The suction port 21 is roughly circular and concentric with the inlet 7, with a diameter slightly larger than that of the inlet 7 by the thickness of the first cylindrical member 19.

The storage tank 8 contains liquid generated when bubbles collide with the inner wall 6A of the casing 6 and collapse. This liquid flows into the storage tank 8 through gaps formed by multiple collars 13 between the lower part of the casing 6 and the base plate 14. A substantially cylindrical first discharge flow path member 22 is attached by welding to the underside of the storage tank 8, and a second discharge flow path member 23 made of a flexible material is fitted tightly to the first discharge flow path member 22 by elastic force. The second discharge flow path member 23 extends into the liquid tank 1 by passing through the top plate 1A of the liquid tank 1, with its tip immersed in the liquid stored in the liquid tank 1. A first discharge flow path 22A is formed in the first discharge flow path member 22, and a second discharge flow path 23A is formed in the second discharge flow path member 23. The storage tank 8 and the liquid tank 1 are connected by the discharge flow paths 22A and 23A. The second discharge flow path member 23 is designed so that the vertical fitting dimension when fitted onto the first discharge flow path member 22 can be increased or decreased, and by increasing or decreasing the fitting dimension, the length between the storage tank 8 and the tip of the second discharge flow path member 23 can be adjusted.

Next, the operation of this configuration will be described.
When the impeller 5 is driven to rotate by the electric motor 9, the centrifugal action of the impeller 5 causes air to be sucked into the casing 6 from the suction port 21 through the suction flow paths 20A, 19A, the inlet 7, and the second inlet 18, and this air is then discharged into the storage tank 8 through the gap between the bottom of the casing 6 and the substrate 14, and is released to the atmosphere.

The bubbles C formed on the liquid surface T are then guided into the casing 6 via the suction flow paths 20A, 19A, the inlet 7, and the second inlet 18, where they collide with the impeller 5. Some of the bubbles C are destroyed and disappear upon this collision, and the resulting droplets, along with the remaining bubbles C, are subjected to centrifugal force by the centrifugal action of the impeller 5 and are transported to the outer periphery of the impeller 5, where they collide with the inner wall portion 6A of the casing 6. Essentially, the remaining bubbles C are destroyed and disappear upon this collision. The liquid produced when the bubbles C disappear flows through the gap between the bottom of the casing 6 and the substrate 14 and is stored in the storage tank 8. The liquid stored in the storage tank 8 then flows through the discharge flow paths 22A, 23A and is returned to the liquid tank 1.

With this operation, the main body 3 is composed of the impeller 5, casing 6, inlet 7, inner wall portion 6A, storage tank 8, and motor 9. The main body 3 is positioned away from the liquid tank 1, and cylindrical members 19 and 20, which form suction flow paths 19A and 20A connecting to the inlet 7, are attached to the casing 6. The suction ports 21 opening at the ends of the suction flow paths 19A and 20A of the cylindrical members 19 and 20 are positioned opposite the bubbles C that form on the liquid surface T of the liquid tank 1. Therefore, the main body 3 does not need to be installed in the liquid tank 1, so the defoaming device 2 can be installed even in a small liquid tank 1.

In addition, discharge flow paths 22A and 23A are provided to connect the storage tank 8 and the liquid tank 1. This allows the liquid resulting from the disappearance of bubbles to be efficiently returned to the liquid tank 1.

In addition, the length between the inlet 7 and the suction port 21 of the cylindrical members 19 and 20 is adjustable. This allows the suction port 21 to be set to the optimal position depending on the liquid level T in the liquid tank 1, making it suitable for a wide range of applications.

FIG. 2 shows another embodiment of the present invention. The same parts as those in the first embodiment are given the same reference numerals and their explanations are omitted, and only the different parts will be explained.
The first cylindrical member 24 is attached by welding to the underside of the substrate 14 at an incline in the vertical direction. The second cylindrical member 25 is made of a flexible material and is fitted tightly onto the first cylindrical member 24 by elastic force. The first suction flow path 24A formed in the first cylindrical member 24 and the second suction flow path 25A formed in the second cylindrical member 25 are inclined in the vertical direction, just like the first cylindrical member 24 and the second cylindrical member 25. The suction port 26 opening at the tip of the second suction flow path 20A is inclined with respect to the liquid level T of the liquid tank 1 and is positioned opposite the bubbles C.

The two leg members 27A, 27B that secure the main body 3 are different in shape. One leg member 27A is roughly L-shaped and is attached to the casing 6 via a collar member 13 with bolt members 15, with its tip fixed to the ground D. The other leg member 27B is roughly L-shaped and shorter in length than the first leg member 27A. It is attached to the casing 6 via a collar member 13 with bolt members 15, with its tip fixed to the top plate 1A of the liquid tank 1.

When the impeller 5 is driven to rotate by the motor 9, the centrifugal force of the impeller 5 draws air into the casing 6 from the suction port 26 through the suction channels 25A and 24A, and then discharges it into the storage tank 8, opening it to the atmosphere. Bubbles C formed on the liquid surface T are guided into the casing 6 via the suction channels 25A and 24A, the inlet 7, and the second inlet 18, and collide with the impeller 5. Some of the bubbles C are destroyed and disappear upon this collision. The resulting droplets, along with the remaining bubbles C, are subjected to centrifugal force by the centrifugal force of the impeller 5 and are transported to the outer periphery of the impeller 5, where they collide with the inner wall 6A of the casing 6. Virtually all of the remaining bubbles C are destroyed and disappear upon this collision. The liquid resulting from the disappearance of the bubbles C is then stored in the storage tank 8. The liquid stored in the storage tank 8 then flows through the discharge channels 22A and 23A and is returned to the liquid tank 1.

With this operation, the cylindrical members 24, 25, which form the suction flow paths 24A, 25A connected to the inlet 7, are attached to the casing 6, and the suction ports 26 opening at the ends of the suction flow paths 24A, 25A of the cylindrical members 24, 25 are positioned opposite the bubbles C that form on the liquid surface T of the liquid tank 1. Therefore, similar to the first embodiment, the main body 3 does not need to be installed in the liquid tank 1, so the defoaming device 2 can be installed even in a small liquid tank 1.

Also, similar to the first embodiment, discharge flow paths 22A and 23A are provided to connect the storage tank 8 and the liquid tank 1, allowing the liquid resulting from the disappearance of bubbles to be efficiently returned to the liquid tank 1.

Furthermore, the length between the inlet 7 and the suction port 26 of the cylindrical members 24 and 25 is adjustable. Therefore, similar to the first embodiment, the suction port 26 can be set to the optimal position depending on the liquid level T in the liquid tank 1, making it suitable for a wide range of applications.

Furthermore, the main body 3 is positioned vertically above the liquid tank 1 at a distance, and the cylindrical members 24, 25 are attached to the casing 6 at a vertical incline. This allows the casing 3 to be installed offset horizontally from vertically above the liquid tank 1, making it possible to install the device even if there is an obstacle above the liquid tank 1, increasing the degree of freedom in installation.

FIG. 3 shows a further embodiment of the present invention. The same parts as those in the first embodiment are given the same reference numerals and their explanations are omitted, and only the different parts will be explained.
Two leg members 28A, 28B are integrally formed on the underside of the storage tank 8, protruding downward from radially symmetrical positions. Each leg member 28A, 28B is formed in the same, approximately L-shape, and has its tip fixed to the top plate 1A of the liquid tank 1.

Operation is generally similar to that of the first embodiment. Air is sucked into the casing 6 through the suction port 21 by the centrifugal action of the impeller 5, and is then discharged into the storage tank 8 through the gap between the bottom of the casing 6 and the base plate 14, opening to the atmosphere. Bubbles C formed on the liquid surface T are guided into the casing 6 and collide with the impeller 5, where some are destroyed and disappear. The resulting droplets, along with the remaining bubbles C, are subjected to centrifugal force by the centrifugal action of the impeller 5 and are transported to the outer periphery of the impeller 5, where they collide with the inner wall portion 6A of the casing 6. This collision destroys and disappears virtually all of the remaining bubbles C, and the liquid resulting from the disappearance of the bubbles C is stored in the storage tank 8. The liquid stored in the storage tank 8 then flows through the discharge flow paths 22A and 23A and is returned to the liquid tank 1.

With this operation, similar to the first embodiment, the main body 3 does not need to be installed in the liquid tank 1, so the defoaming device 2 can be installed even in a small liquid tank 1. Furthermore, by providing discharge flow paths 22A and 23A connecting the storage tank 8 and the liquid tank 1, the liquid resulting from the disappearance of bubbles can be efficiently returned to the liquid tank 1. Furthermore, the length between the inlet 7 and the suction port 21 of the cylindrical members 19 and 20 is adjustable, so the suction port 21 can be set to an optimal position depending on the liquid level T in the liquid tank 1, making it suitable for a wide range of applications.

In addition, the leg members 28A and 28B are formed integrally with the storage tank 8. This eliminates the need to assemble the storage tank 8 and the leg members 28A and 28B, simplifying assembly.

In each of the above-described embodiments, two leg members 4A, 4B, 27A, 27B, 28A, and 28B are provided, but this is not limited to this, and it is of course possible to provide one leg member or three or more leg members.

1: Liquid tank 2: Defoamer 3: Main body 5: Impeller 6: Casing 6A: Inner wall portion 7: Inlet 8: Storage tank 9: Motor 19, 24: First cylindrical member (cylindrical member)
19A, 24A: First suction flow path (suction flow path)
20, 25: Second cylindrical member (cylindrical member)
20A, 25A: Second suction flow path (suction flow path)
21, 26: Suction port T: Liquid level C: Foam

Claims (4)

a main body comprising an impeller having a plurality of blades extending radially from a center, a casing accommodating the impeller therein and having a plate-like base plate attached thereto , an inlet formed through the base plate on the front side of the casing facing the impeller so as to open toward the center of the impeller, an inner wall portion of the casing on the outer periphery of the impeller against which bubbles migrate from the inlet to the outer periphery of the impeller due to centrifugal force caused by the centrifugal action of the impeller and collide to be destroyed, a storage tank for storing liquid resulting from the bubbles colliding with the inner wall portion of the casing, and an electric motor for driving the impeller from behind the casing, and leg members for fixing the main body to a liquid tank so as to be spaced apart vertically above the liquid tank, wherein a cylindrical member having a suction flow path attached to the base plate of the casing, the suction flow path of the cylindrical member being connected to the inlet, and the cylindrical member having a suction port opening at a tip of the suction flow path, positioned to face bubbles formed on the liquid surface of the liquid tank. The defoaming device described in claim 1, characterized in that a discharge flow path is provided connecting the storage tank and the liquid tank. 3. The foam defoaming device according to claim 1, wherein the cylindrical member is attached to the casing at an inclination in the vertical direction. A defoaming device as described in any one of claims 1 to 3, characterized in that the length dimension of the tubular member between the inlet and the suction port is adjustable.