Overflow device for water tank

An aquarium overflow device is capable of preventing inadvertent supply of water in an aquarium from being supplied to an outside during, e.g., power failure. An aquarium overflow device is for supplying the water in an aquarium to an external device outside the aquarium. The device is equipped with a reversed U-shaped siphon pipe for supplying the water in the aquarium to an outside of the aquarium, the siphon pipe having an inlet side end portion disposed in the aquarium and an inlet side end portion disposed with the outlet side end portion disposed outside the aquarium, a suction device for sucking an inside of the siphon pipe, the suction device being connected to an upper portion of the siphon pipe, and an air introduction device for introducing air to an upper portion in the siphon pipe when suction by the suction device stops.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is the National Stage of PCT/JP2007/064151 filed on Jul. 18, 2007, which claims priority under 35 U.S.C. §119 of Japanese Application No. 2006-228892 filed on Aug. 25, 2006. The international application under PCT article 21(2) was not published in English.

TECHNICAL FIELD

The present invention relates to an overflow device for supplying water in an aquarium such as an aquarium for ornamental fish to an external equipment such as a filtering device.

BACKGROUND ART

When keeping ornamental fish, such as, e.g., saltwater fish or freshwater fish, in an aquarium, a filtering device is generally installed for the purpose of keeping the water in the aquarium clean.

As an aquarium filtering device, an underwater installation type filtering device designed to be installed within an aquarium and an outside installation type filtering device designed to be installed outside an aquarium are well known. As compared with the underwater installation type filtering device, the outside installation type filtering device is suitable in terms of enlarging the size and can have excellent filtration capacity.

Conventionally, for the purpose of supplying the water in the aquarium to an outside installation type filtering device or returning the water in the filtering device to the aquarium, an overflow device is used.

As disclosed in the following Patent Document 1, a conventional overflow device includes a tank-outside water storing portion to be disposed on the side wall outside surface of an aquarium, and an inverted U-shaped siphon pipe to be disposed so as to straddle the aquarium inside and the aquarium outside, and an overflow pipe provided in the tank-outside water storing portion. It is configured such that the water in the aquarium is supplied to the tank-outside water storing portion via the siphon pipe and flows out via the overflow pipe to be supplied to a filtering device disposed outside the aquarium.

The filtering device disposed outside the aquarium is provided with a discharge pump so that the water filtered by the filtering device is forcibly discharged (returned) by the discharge pump to the aquarium via an outlet pipe.Patent Document 1: Japanese Utility Model Registration No. 3018619 (FIG. 3)

DISCLOSURE OF THE INVENTION

Problems to be Solved by the Invention

In a conventional aquarium overflow device disclosed in the abovementioned Patent Document 1, even in cases where the discharge pump of the filtering device stops and therefore the returning of the water in the filtering device to the aquarium is interrupted, the water in the aquarium will be continuously supplied to the filtering device via the siphon pipe unless the water level of the aquarium drops lower than the inlet side end portion of the siphon pipe. This causes excessive water supply to the filtering device, which in turn may cause a water level exceeding an allowable water level or even the water overflow.

The present invention was made in view of the aforementioned and/or other problems of the related technique. Preferable embodiments of the present invention can improve remarkably existing methods and/or apparatuses.

The present invention was made to solve the problems of the aforementioned prior art and aims to provide an aquarium overflow device capable of preventing unintentional supplying of the water in the aquarium to an outside of the aquarium.

The other objects and advantages of the present invention will be apparent from the following preferable embodiments.

Means to Solve the Problems

In order to attain the aforementioned objects, the present invention has the following structure.

[1] An aquarium overflow device for supplying water in an aquarium to an external device disposed outside the aquarium, the overflow device comprising:

an inverted U-shaped siphon pipe for supplying the water in the aquarium to an outside of the aquarium, the siphon pipe having an inlet side end portion to be disposed in the aquarium and an outlet side end portion to be disposed outside the aquarium;

suction means connected to an upper portion of the siphon pipe and configured to suck an inside of the siphon pipe; and

air introducing means for introducing air into the upper portion in the siphon pipe when suction by the suction means is stopped.

In the present invention, the air introducing means is configured to directly introduce air into the upper portion of the siphon pipe, which is different from introducing air from an end portion of the siphon pipe.

The upper portion of the siphon pipe is a part constituted by a returning portion of the siphon pipe or the vicinity thereof.

[2] The aquarium overflow device as recited in the aforementioned Item 1, further comprising an inverted U-shaped discharge pipe having an inlet side end portion disposed outside the aquarium and an outlet side end portion disposed inside the aquarium,

wherein it is configured such that water fed from the external device is introduced into the discharge pipe from the inlet side end portion and then discharged into the aquarium from the outlet side end portion by water supply means,

wherein a backward flow preventing opening is provided at an upper portion of the discharge pipe, and

wherein it is configured such that when water supply from the external device by the water supply means is stopped, air is introduced into the discharge pipe from the backward flow preventing opening to prevent backward flow of the water.

[3] The aquarium overflow device as recited in the aforementioned Item 2,

wherein the suction means includes a suction tube having one end connected to the upper portion of the siphon pipe, a suction pump connected to the other end of the suction tube, and a connection tube having one end connected to the upper portion of the siphon pipe and the other end connected to an upper portion of the discharge pipe,

wherein the connection tube doubles as the air introducing means, and

wherein, when the suction pump and the water supply means are being driven, an inside of the siphon pipe is sucked by a suction function caused by a water flow in the discharge pipe via the connection tube and also an inside of the siphon pipe is sucked by the suction pump via the connection tube, on the other hand, when the suction pump and the water supply means are stopped, the air introduced into the discharge pipe from the backward flow preventing opening is introduced into the siphon pipe via the connection tube.

[4] The aquarium overflow device as recited in the aforementioned Item 2,

wherein as the suction means and the air introducing means, a connection tube having one end connected to the upper portion of the siphon pipe and the other end connected to an upper portion of the discharge pipe is provided, and

wherein, when the suction pump and the water supply means are being driven, an inside of the siphon pipe is sucked by a suction function caused by a water flow in the discharge pipe via the connection tube, on the other hand, when the suction pump and the water supply means are stopped, the air introduced into the discharge pipe from the backward flow preventing opening is introduced into the siphon pipe via the connection tube.

The aquarium overflow device as recited in the aforementioned Item 1 or 2,

wherein the suction means includes a suction tube having one end connected to an upper portion of the siphon pipe and a suction pump connected to the other end of the suction tube,

wherein the air introducing means includes an air introducing tube having one end connected to the upper portion of the siphon pipe and a control valve connected to the other end of the air introducing tube and configured to open and close in response to driving/stopping of the suction pump, and

wherein when the suction pump is being driven, the control valve is maintained in a closed state and an inside of the siphon pipe is sucked by the suction pump via the suction tube, on the other hand, when the suction pump is stopped, the control valve is kept open so that air is introduced into the siphon pipe via the air introducing tube.

Effects of the Invention

According to the aquarium overflow device of the invention [1], in the event that the driving of the suction means is stopped by, e.g., power failure, since air is introduced into the middle upper portion of the siphon pipe, suction of the water in the aquarium into the siphon pipe is intercepted by the introduced air, which in turn can immediately stop water supply by the siphon pipe.

According to the aquarium overflow device of the invention [2], in the event that driving of the water supply means is stopped by, e.g., power failure, since air is introduced into the discharge pipe via the backward flow preventing opening, backward flow of the water in the aquarium to the discharge pipe can be prevented, which in turn can prevented water supplying of the water to the external device.

According to the aquarium overflow device of the inventions [3] to [5], at the time of, e.g., power failure, air is assuredly introduced into the siphon pipe, which more assuredly prevent unexpected water suction by the siphon pipe.

BEST MODE FOR CARRYING OUT THE INVENTION

First Embodiment

FIG. 1is a perspective view showing an aquarium system according to a first embodiment of the present invention. As shown in the figure, the aquarium system includes, as fundamental structural elements, an aquarium1, an independent installation type filtering device2which is to be installed independently from the aquarium1, an overflow device5for discharging water W from and introducing water W to the aquarium1, an inlet hose11, such as, e.g., an inlet pipe, for supplying water from the overflow device5to the filtering device2, and an outlet hose12, such as, e.g., an outlet pipe, for sending water from the filtering device2to the overflow device5.

As shown inFIGS. 1 to 4, the overflow device5is equipped with an overflow box50to be straddled on the side wall upper end of the aquarium1. In the overflow box50, a siphon pipe55, a discharge pipe56, and a sound insulating cover57are mounted.

The overflow box50is constituted by an integrally formed resin molded article including a box-shaped tank-inside water storage portion51having an open upper end and configured to be disposed along a side wall inner surface of the aquarium1, a box-shaped tank-outside water storage portion52having an open upper end and configured to be disposed along a sidewall outer surface of the aquarium1, and a bridge connection portion53bridging upper end portions of both the water storage portions51and52and connecting both the water storage portions51and52.

One side wall portion of the tank-inside water storage portion51has a number of vertically extended slit-like water passage holes511arranged in parallel in the horizontal direction at certain intervals, so that the water W in the aquarium flows into the tank-inside water storage portion51via the water passage holes511.

The one side wall portion of the tank-inside water storage portion51is provided, at the lower end edge portion thereof, with a discharge opening512to which a discharge nozzle513is connected.

The siphon pipe55is constituted by an inverted U-shaped or inverted-shaped wide-width tubular member and configured so that the inlet side end portion is placed in the tank-inside water storage portion51, the intermediate bent portion is placed on the bridge connection portion53, and the outlet side end portion is placed in the tank-outside water storage portion52. Thus, in the state in which the siphon pipe55is filled with water W, if the water level at the side of the tank-inside water storage portion51is higher than the water level at the side of the tank-outside water storage portion52, the water W in the tank-inside water storage portion51is fed to the side of the tank-outside water storage portion52via the siphon pipe55due to the difference in atmospheric pressure.

At the upper center of the intermediate bent portion (upper portion) of the siphon pipe55, a suction hole555is provided. To this suction hole555, a water suction intercept mechanism8, which will be detailed, is connected.

At one end portion of the lower wall of the tank-outside water storage portion52, an inlet hose connection521is provided. Corresponding to this connection521, an overflow pipe54having a specified height is also provided on the lower wall upper surface of the water storage portion52.

The inlet side end portion of the inlet hose11made of a flexible hose is connected to the lower side of the inlet hose connection521. The outlet side end portion of the inlet hose11is connected to the filtering device2as will be explained later so that the water W flowing out of the overflow device5is introduced into the filtering device2via the inlet hose11.

The tank-outside water storage portion52is provided with a sound insulating cover57. This sound insulating cover57is formed into an above-water portion entirely covering type which covers the peripheral four sides and the upper surface of the region including the overflow pipe54above the water surface. Furthermore, the sound insulating cover57is provided with water flowing cutout portions571at the lower end of the peripheral side walls so that the water W stored in the tank-outside water storage portion52can flow into the sound insulating cover57, i.e., the overflow pipe54side, via the water flowing cutout portions571.

Air release holes572and572are formed in the upper wall of the sound insulating cover57so that the inside of the sound insulating cover57can be maintained to the atmosphere pressure by allowing the air to flow in and out of the sound insulating cover57via the air release holes572.

At the other end portion of the lower wall of the tank-outside water storage portion52, an outlet hose connection523is provided.

A discharge pipe56disposed in the overflow box50is formed into an inverted U-shape or-shape. The inlet side end portion of the discharge pipe56is fluidly communicated with the connection523of the tank-outside water storage portion52. The middle bent portion is disposed along the bridge connection portion53, and the outlet side end portion is fluidly communicated with the discharge nozzle513of the discharge opening512of the tank-inside water storage portion51.

As shown inFIGS. 3 and 5, at the upper end portion of the tank-inside pipe portion of the discharge pipe56, a backflow preventing hole561is provided. As will be explained later, this backflow preventing hole561prevents the water W in the aquarium from flowing back to the side of the filtering device2from the side of the discharge pipe56in the event that the discharge pump35suddenly stops due to, e.g., unexpected situations.

To the lower side of the outlet hose connection523of the overflow device5, an outlet side end portion of the outlet hose12is connected. While, the inlet side end portion of the outlet hose12is connected to the filtering device2as will be explained later. The water W discharged from the filtering device2is introduced into the overflow device5via the outlet hose connection523via the outlet hose12, and the water is then discharged into the aquarium from the discharge nozzle513via the discharge pipe56.

Furthermore, at the upper center of the intermediate bent portion (upper portion) of the discharge pipe56, a suction hole565is provided. To the suction hole565, the water suction intercept mechanism8, which will be explained later, is connected.

As shown inFIGS. 2,4and5, the water suction intercept mechanism8of this overflow device5is equipped with, e.g., a suction pump80, a suction tube81, a connection tube82, a T-shaped pipe joint86, a pipe joint member87, etc.

The T-shaped pipe joint86has three connecting portions communicated with each other. The first connecting portion of this pipe joint86is fluidly connected to the suction hole555of the siphon pipe55. Furthermore, the second connecting portion of the pipe joint86is fluidly connected to one end of the suction tube81. Also fluidly connected to the third connecting portion of the pipe joint86is one end of the connection tube.

At the other end of the suction tube81, an electrically-operated suction pump80as suction means is connected so that the inside of the suction tube81is sucked by the suction operation of this pump80.

The other end of the connection tube82is fluidly connected to the suction hole565of the discharge pipe56via the pipe joint member87.

In the water suction intercept mechanism8, in the state in which water is normally circulating, a negative pressure is given to the inside of the suction tube81by the suction pump80, which causes suction of the water or air (bubbles) in the siphon pipe55toward the pump80via the suction tube81. At the same time, the flowing of the water in the discharge pipe56causes a negative pressure in the connection tube82, which causes suction of water and/or air (bubbles) in the siphon pipe55into the discharge pipe56via the connection tube82. Although the detail explanation will be made later, in the overflow device5of this embodiment, it is configured such that, in cases where the driving of the suction pump80and/or the discharge pump35, which will be explained later, is interrupted due to, e.g., power failure, air will be introduced into the siphon pipe55to immediately stop supply of water (suction of water) by the siphon pipe55.

As shown inFIGS. 2 and 3, the overflow device5is provided with height adjusting screws531and531on both sides of the bridge connection portion53. The shaft tip end of each of the screws531and531is in contact with the upper end surface of the aquarium side wall via the contact frame532. By adjusting the height of the overflow device5with respect to the aquarium1by changing the screwed amount of each of the screws531and531, the water level in the overflow device5can be adjusted.

The overflow device5is provided with a perpendicular attitude control screw535on the lower surface of the tank-outside water storage portion52via the screw tube member536. The head portion of the screw535is in contact with the outer surface of the aquarium side wall. Therefore, by adjusting the distance between the bottom portion of the tank-outside water storage portion52and the aquarium outer wall surface by changing the screwed amount of the screw535, the horizontal attitude of the overflow device5can be adjusted.

As shown inFIGS. 6 to 9, the filtering device2is equipped with a casing main body21having an opening at its upper end.

In this casing main body21, the front portion constitutes a functional component zone Z1and the rear side behind the functional component zone Z1constitutes a filtration zone Z2.

A functional component unit3is disposed in the functional component zone Z1of the casing main body21, and a filtration unit4is disposed in the filtration zone Z2.

On the side wall inner surfaces of the casing main body21, guide protrusions25continuously extending vertically between the functional component zone Z1and the filtration zone Z2are formed.

Among the upper openings of the casing main body21, the upper opening at the side of the functional component zone Z1is covered with an upper wall member34of the functional component unit3, and the upper opening at the side of the filtration zone Z2is covered with a casing lid22.

In this first embodiment, the casing main body21, the casing lid22and the upper wall member34of the functional component unit3constitute the casing20.

As shown inFIGS. 6 to 11, the functional component unit3includes a unit frame31, a discharge pump35, a protein skimmer6, various connection members, and various pipes.

The unit frame31is provided with a base plate311having a rectangular shape as seen from the top to be placed on the bottom surface of the casing main body21, three vertical frames312upwardly extended from three corners of the base plate311, and an inlet chamber32positioned at the upper side of the vertical frames312.

Further, the inlet chamber32has an inlet chamber main body33supported by the upper ends of the vertical frames312and an upper wall member34detachably attached to the upper end opening portion of the inlet chamber main body33.

The inlet chamber main body33is disposed so that the upper end open portion thereof corresponds to the upper end opening portion at the side of the functional component zone Z1of the casing main body21. Therefore, the upper wall member34closing the upper end opening portion of the inlet chamber main body33also functions as a lid member (a part of the upper wall) of the casing main body21.

The upper wall member34has an inlet hose connection341, an outlet hose connection342, a protein skimmer connection343and a stone replacement operation portion344.

To the inlet hose connection341, the outlet side end portion of the inlet hose11connected to the overflow device5is fluidly connected. While, to the outlet hose connection342, the inlet side end portion of the outlet hose11connected to the overflow device5is fluidly connected.

The inlet hose connection341has, at the lower surface side of the upper wall member34, a flow dividing plate346. As shown inFIG. 12, this flow dividing plate346has chamber communication holes347communicated with the inlet chamber32, and is connected to the inlet side end portion of the protein skimmer connection pipe67. Thus, among the water W introduced through the inlet hose11, a part of the water W is introduced into the protein skimmer6via the protein skimmer connection pipe67, while the rest of the water W is introduced into the inlet chamber32via the chamber communication holes347.

In the rear wall of the inlet chamber main body33, a filtration zone communication opening331communicated with the filtration zone Z2is formed. The water W introduced into the inlet chamber32via the inlet hose connection341is introduced into the filtration zone Z2through the filtration zone communication opening331.

The discharge pump35is fixed to the upper surface of the base plate311of the unit frame31. The outlet port of the discharge pump35is in fluid communication with the lower end of the discharge pipe351. The upper end of this discharge pipe351is penetrated through the inlet chamber32and is in fluid communication with the discharge hose connection342of the upper wall member34. Thus, it is configured such that the water W stored in the bottom portion of the casing main body21is fed to the discharge pipe351by the discharge pump35and then the water W passes through the outlet hose12to be supplied to the overflow device5.

The protein skimmer6has a vertically disposed skimmer main pipe61with the lower end fixed to the base plate311of the unit frame31. The upper end of the skimmer main pipe61penetrates the inlet chamber32to be disposed above the upper part of the upper wall member34.

Within the upper end portion of the skimmer main pipe61, a tapered pipe62with a radius gradually decreasing towards the upper portion thereof is provided. Further provided is a protein skimmer cup63covering the upper tapered portion of the tapered pipe62. This protein skimmer cup63is provided with a discharge spout631for discharging organic series contaminants, such as, e.g., protein, accumulated in the cup as will be described later.

The protein skimmer connection pipe67penetrates in the upper portion of the skimmer main pipe61, so that a part of the water W divided by the flow dividing plate346in the chamber upper wall member34is introduced into the skimmer main pipe61of the protein skimmer6via the connection pipe67.

In the protein skimmer6, the lower end of the inclined pipe64is fluidly connected to the lower end portion of the skimmer main pipe61. The inclined pipe64is placed so that it extends obliquely upward from the lower end portion of the skimmer main pipe61. The upper end of the inclined pipe64penetrates the inlet chamber32to be connected to the stone replacement operation portion344of the upper wall member34.

The inclined pipe64is provided with blocking members651and652fitted and attached to the upper end and the lower end of the inclined pipe64. Also, in the inclined pipe64, a hard air supplying pipe65is disposed in a state in which the pipe penetrates both the blocking members651and652. The tip end of the air supplying pipe65is placed at the lower end portion of the skimmer main pipe61.

A wood stone66as a bubble generating means is placed at the lower end portion of the skimmer main pipe61, and the wood stone66is communicated with the tip end of the air supplying pipe65. The wood stone66is formed into an elongated cylindrical shape with a diameter smaller than the inner diameter of the inclined pipe64so that it can be inserted in the inclined pipe64. Therefore, by pulling out the air supplying pipe65from the inclined pipe64, the wood stone66can be taken out from the skimmer main pipe61together with the air supplying pipe65via the inclined pipe64. On the other hand, by inserting the air supplying pipe65into the inclined pipe64from the upper end portion together with the wood stone66attached to the tip end of the air supplying pipe65, the wood stone66can be placed at a predetermined position in the lower portion of the skimmer main pipe61.

In this way, the wood stone66can be taken in and out without troublesome operations, such as, disassembling operations of the other components.

The wood stone66has a number of fine pores, and can generate a number of bubbles by supplying air to the wood stone66via the air supplying pipe65in a state in which the wood stone66is immersed in the stored water W in the skimmer main pipe61. Organic series contaminants, such as, e.g., protein, contained in the water adhere to the generated bubbles, and they move upwards. The upwardly moved proteins further go up through the skimmer main pipe61to be discharged from the upper end of the tapered pipe62, collected within the protein skimmer cup63, and then discharged to the outside via the discharge spout631.

At the peripheral wall lower end of the skimmer main pipe61of the protein skimmer6, the lower end of the overflow pipe68is connected. While, the upper end of the overflow pipe68is disposed at the lower portion of the inlet chamber38of the filtration zone Z1. Thus, when the water W supplied to the skimmer main pipe61is stored more than the specified amount, the water W is discharged to the inside of the casing20but outside the protein skimmer6via the overflow pipe68.

In the functional component unit3having the abovementioned structure, the inlet chamber32and the base plate311are each formed to have a plane shape corresponding to the plane cross-section of the functional component zone Z1of the casing main body21. In the state in which the functional component unit3is assembled, the unit3can be inserted into and removed from the functional component zone Z1of the casing main body21via the upper end opening thereof. Furthermore, at the time of the insertion/removal operation thereof, the rear ends of both side portions of the inlet chamber32and those of the base plate311of the unit3are engaged with and guided by the guide protrusions25formed on the inner side surfaces of the casing main body21, so that the insertion/removal operation of the unit3can be performed smoothly. Furthermore, in a state in which the unit3is accommodated, the rear ends of both side portions of the inlet chamber32and those of the base plate311are engaged with the guide protrusions25to be positioned, so that the entire unit3is disposed within the casing main body21in a fitted manner.

In this first embodiment, despite whether the filtration unit4, which will be explained later, is accommodated within the casing main body21, the functional component unit3can be inserted and removed from the casing main body21.

As shown inFIGS. 8 and 13, the filtration unit4includes a lower bucket41, a middle bucket42, a water spray tray43, a drain board44and a gutter member45.

Each of the buckets41and42is formed into an upper opened box shape and is provided with a number of water spraying holes411and421formed in the bottom wall, so that the water W supplied to the inside of the buckets41and42are poured out downward through the water spraying holes411and421.

On the bottom surface of the casing main body21at the side of the filtration zone Z2, spacer protrusions211are formed, so that the lower bucket41is placed on the spacer protrusions211. Thus, the lower bucket41is accommodated in the filtration zone Z2of the casing main body21with a substantial space formed between the bottom surface of the filtration zone Z2and the bottom surface of the lower bucket41.

Furthermore, the middle bucket42is accommodated in the filtration zone Z2of the casing main body21with the middle bucket placed on the lower bucket41.

The water spray tray43is formed into an upper opened shallow box shape and has a number of water spraying holes431formed in the bottom wall thereof. Also, the water spray tray43is provided with spacer protrusions432formed on the bottom surface thereof.

The water spray tray43is accommodated in the filtration zone Z2of the casing main body21with the water spray tray placed on the middle bucket42.

The drain board44is formed into a shape corresponding to the inner circumferential shape of the water spray tray43, and has a number of water spraying holes441.

This drain board44is placed on the spacer protrusions432of the water spray tray43. Thus, the drain board44is accommodated in the water spray tray43in a fitted manner with a substantial space formed between the drain board and the bottom of the water spray tray43.

The gutter member45is formed into an upper opened channel shape and has a number of water spraying holes451formed in the bottom wall. The front end (the functional component zone side end portion) of the gutter member45is opened, while the rear end is closed.

The gutter member45is disposed on the water spray tray43via the drain board44with the front opened end portion facing the filtration zone communication opening331of the inlet chamber32of the functional component unit3.

The gutter member45is provided with a water guiding tongue portion452forwardly extended from the bottom wall front end thereof. This tongue portion452is inserted into the filtration zone communication opening331and engaged with the inlet chamber32of the functional component unit3. Consequently, the stored water W in the inlet chamber32is guided by the tongue portion452and supplied smoothly to the gutter member45via the communication opening331.

In the filtration unit4constructed as explained above, it is configured such that each of the constituent components41to45can be inserted into and detached from the upper end opening of the filtration zone Z2of the casing main body21.

The buckets41and42and the water spray tray43are each formed into a shape corresponding to the plan cross-sectional shape of the filtration zone Z2. Therefore, when these members41to43are insert into or detached from the filtration zone Z2of the casing main body21, front both side portions of the buckets41and42and those of the water spray tray43are engaged with and guided by the guiding protrusions25formed on the inner side surfaces of the casing21, so that insertion/removal operation of each of the members41to45can be performed with high dimensional accuracy. In a state in which the members41to45are accommodated, front both side portions of the buckets41and42and those of the water spray tray43are engaged with the guide protrusions25in a positioned manner, so that each of the members41to45is accommodated in the casing main body21in a fitted manner.

Furthermore, in the first embodiment, despite whether the functional component unit3is accommodated in the casing main body21, it is constituted such that each of the components41to45of the filtration unit4can be inserted into and detached from the casing main body21.

To the upper end opening of the filtration zone Z2of the casing main body21, the aforementioned casing lid22is detachably attached via a packing (not shown).

As mentioned above, the casing20is constituted by attaching the casing lit22and the upper wall member34of the functional component unit3to the casing main body21. The interior of the casing20is open to the atmosphere. For example, the casing lid22has an atmospheric communication opening221, so that air is allowed to go into and out of the casing20via the communication opening221. Thus, the interior of the casing20is open to the atmosphere.

InFIG. 1, the reference numeral “352” denotes a power cord of the discharge pump35, the reference numeral “655” denotes an air supplying means for supplying air to the wood stone66via the air supplying pipe65.

In the abovementioned aquarium system, the following operational preparation is performed before the actual operation.

In preparing the operation, as shown inFIG. 8, filtration materials71to73are initially set to the filtering device2. In the lower bucket41of the filtration unit4, a filtration material71, such as, e.g., Siporax, in which anaerobic filtering bacteria can be grown, is accommodated to perform biofiltration. In the middle bucket42, a filtration material72, such as, e.g., bio ball, in which aerobic filtration bacteria can be grown, is accommodated to perform biofiltration. Furthermore, in the water spray tray43, a filtration material73, such as, e.g., wool or activated carbon, is accommodated via the drain board44to perform physical filtration.

Further, as explained above, the overflow device5is set so as to straddle the side wall upper end of the aquarium1. In this state, the tank-inside water storage portion51of the overflow device5is immersed in the water W in the aquarium to a predetermined level, so that the water W in the aquarium flows into the storage portion51via the water passage holes511. Thus, a specified amount of water is stored in the tank-inside water storage portion51.

Also accommodated in the tank-inside water storage portion51of the overflow device5is a physical filtration material (not shown), such as, e.g., sponge.

Furthermore, hoses11and12are set between the filtering device2and the overflow device5. In detail, the inlet side end portion of the inlet hose11is fluidly connected to the inlet hose connection521of the overflow device5, while the outlet side end portion thereof is fluidly connected to the inlet hose connection341of the filtering device2. Also, the inlet side end portion of the outlet hose12is fluidly connected to the outlet hose connection342of the filtering device2, while the outlet side end portion thereof is fluidly connected to the outlet hose connection523of the overflow device5. Furthermore, the sound insulating cover57is set in the tank-outside water storage portion52so as to cover the entire periphery of the overflow pipe54.

Next, in the tank-outside water storage portion52of the overflow device5set on the aquarium side wall, water W is filled to a level slightly lower than the water level of the tank-inside water storage portion51.

After pouring a certain amount of water W in the casing20of the filtering device2, the operation of the aquarium system is initiated. That is, the discharge pump35of the filtering device2and the suction pump80of the overflow device5are activated, and air is supplied to the wood stone66of the protein skimmer6.

With this, in the casing20of the filtering device2, water W is fed to the discharge pipe351by the discharge pump35, and the water W is fed to the discharge pipe56of the overflow device5through the outlet hose12. The water W fed to the discharge pipe56is discharged to the aquarium1from the discharge nozzle513. Thus, the water W in the filtering device2is fed to the aquarium1.

On the other hand, in the overflow device5, the air in the siphon pipe55is sucked from the suction hole555of the siphon pipe55via the suction tube81, so that the siphon pipe55is filled with water W. The water level difference between the aquarium1and the tank-outside water storage portion52of the overflow device5causes a suction function (siphon phenomenon) of the siphon pipe55, which in turn causes the water W in the aquarium to be supplied from the tank-inside water storage portion51to the tank-outside water storage52via the siphon pipe55. Furthermore, the water W flows into the overflow pipe54and is supplied to the casing20of the filtering device2through the inlet hose11.

The water W fed to the casing20is divided by the flow dividing plate346at the inlet hose connection341, and most of the water W is introduced into the inlet chamber32through the chamber communication holes347, and the remaining water W is introduced into the skimmer main pipe61of the protein skimmer6through the protein skimmer connection pipe67.

Protein contained in the water W introduced into the protein skimmer6is removed. That is, a wood stone66is disposed in the water introduced into and stored in the skimmer main pipe61, and a number of bubbles are generated from the wood stone66. The protein in the water adheres to these bubbles, floats, sequentially moves upwards, and gradually goes upward through the skimmer main pipe61. These ascended bubbles with protein are discharged from the upper end of the tapered pipe62, collected in the protein skimmer cup63and discharged to the outside from the discharge spout631. Thus, only protein is discharged and removed from the water.

The water W from which protein is removed goes through the overflow pipe68of the protein skimmer6and discharged into the casing which is outside the protein skimmer6.

On the other hand, the water W introduced into the inlet chamber32is supplied to the gutter member45in the filtration zone Z2through the filtration zone communication opening331.

While flowing the gutter member45, the water supplied to the gutter member45is dispersed and drops through a number of water spraying holes451, and is supplied to nearly the entire area of the filtration material73of the water spray tray43in a dispersed manner.

After physically filtered by the filtration material73, the water W supplied to the filtration material73, such as, e.g., wool or activated carbon, passes through the drain board44, and is dispersed and drops through a number of water spraying holes431of the water spray tray43and then supplied to nearly the entire area of the filtration material72of the middle bucket42.

The water W supplied to the filtration material72, such as, e.g., a bio ball, in the middle bucket42is biologically filtered by the aerobic filter bacteria adhered to the filtration material72, and then dispersed and drops through a number of water spraying holes421to be supplied to nearly the entire area of the filtration material71of the lower bucket41.

The water W supplied to the filtration material71, such as, e.g., Siporax, in the lower bucket41is biologically filtered by the anaerobic filter bacteria adhered to the filtration material71, and supplied to the bottom portion of the casing20through a number of water spraying holes511.

The water W filtered as mentioned above flows from the filtration zone Z2to the functional component zone Z1, and is fed to the discharge pipe351by the discharge pump35and then supplied to the aquarium1in the same manner as mentioned above.

In this way, the water W consecutively circulates between the aquarium1and the filtering device2, and the water W in the aquarium1is filtered by the filtering device2to be always kept clean.

On the other hand, during the normal operation of this aquarium system, in the water suction intercept mechanism8of the overflow device5, the driving of the suction pump80is continuously performed, so that the water and/or air in the siphon pipe55is always sucked toward the suction pump80via the suction tube81. At the same time, the suction function caused by the water flow in the suction pipe56causes the water or air in the siphon pipe55to be always sucked into the discharge pipe56.

In the aquarium system of this first embodiment, even if the water pump35suddenly stops due to unforeseen situations, such as, e.g., electric power failure, it is prevented that the water W in the aquarium flows backward through the outlet pipe56to be supplied to the filtering device2. It also can be prevented that the water W in the aquarium is supplied to the filtering device2by the siphon pipe55.

In detail, when the water supply to the outlet hose12by the discharge pump35stops, the water W in the outlet hose12flows backward toward the filtering device2by the gravitational force of the water, which in turn causes suction of the water W in the aquarium into the inverted U-shaped discharge pipe56of the overflow device5and starts backward flow. In the first embodiment, however, the backflow preventing hole561formed in the upper end portion of the tank-inside pipe portion of the discharge pipe56causes introduction of air into the discharge pipe56via the backflow preventing hole561when the water W in the discharge pipe56starts backward flow. This prevents suction of the water W in the aquarium into the discharge pipe56, which in turn prevents the water in the aquarium from flowing back to the filtering device2. If there is no backflow preventing hole561, when the discharge pump35stops, the water in the outlet hose12starts backward flow. Simultaneously with the backward flow of the water, the water W in the aquarium is sucked into the discharge pipe56due to the siphon phenomenon, resulting in backward flow of the water to the filtering device2.

Furthermore, even in cases where the discharge pump35stops, if no countermeasure is taken, the water W in the aquarium will be sucked from the siphon pipe55of the overflow device5to be supplied to the filtering device2through the inlet hose11. On the other hand, in this embodiment, since the siphon pipe55and the discharge pipe56are connected via the connection tube82, the water supply by the siphon pipe55can be interrupted. In other words, when the discharge pump35stops, the air will be introduced into the discharge pipe56as explained above, which causes air to be introduced into the siphon pipe55via the backflow preventing hole561, the discharge pipe56and the connection tube82. At this time, since the suction pump80is being stopped due to the power failure, the air introduced into the siphon pipe55will not be sucked and/or discharged via the suction tube81, causing a sufficient amount of air to be introduced into the upper portion of the siphon pipe55. This air causes the water in the siphon pipe55to be divided into the water at the inlet side pipe portion of the siphon pipe55and the water at the outlet side pipe portion of the siphon pipe55. This prevents the water W in the aquarium from being sucked into the siphon pipe55, resulting in immediate interception of the water supply by the siphon pipe55.

As will be understood from the above, in this first embodiment, even if the discharge pump35suddenly stops due to, e.g., power failure, the backward flow of the water W in the aquarium to the outlet hose12can be prevented, and at the same time, the supply of the water W by the siphon pipe55can be automatically interrupted without delay. Therefore, troubles, such as, e.g., water overflow or water leakage, due to the backward flow of the water or the excessive supply of the water, can be prevented, which can further improve the performance dependability.

In the first embodiment, even if the water supply by the siphon pipe55and the discharge pipe56is stopped due to power failure, when the power supply to the discharge pump35and the suction pump80is resumed by the recovery of the power failure, the system returns to its normal state automatically.

In detail, when the discharge pump35is driven, the water in the filtering device2will be forcibly discharged into the aquarium via the outlet hose12and the discharge pipe56. When water flow is once generated in the outlet hose12, in the same manner as a Venturi tube function, a negative pressure will be given to the connection tube82from the side of the discharge pipe56. Accordingly, by this suction function, the air in the siphon pipe55is sucked and discharged via the connection tube82, and at the same time, the driving of the suction pump80is resumed, which causes the air in the siphon pipe55to be sucked and discharged via the suction tube81. Thus, the air in the siphon pipe55is discharged, causing the water W in the aquarium to be sucked by the siphon pipe55and supplied to the filtering device2.

When the power failure is recovered, the system will return to its normal state, and therefore no troublesome restoration operations will be required and it becomes possible to prevent harmful influences due to power failure during owner's absence.

In the filtering device2of this first embodiment, the casing20is clearly divided into the functional component zone Z1and the filtration zone Z2and the functional component unit3is detachably accommodated in the functional component zone Z1. Therefore, the functional component unit3can be easily detached, so that the maintenance and repair of the pump35and/or the protein skimmer6constituting the unit3can be easily performed. Furthermore, the functional component unit3includes the pump power cord and various pipes as well as the inlet hose connection341, the outlet hose connection342, the protein skimmer connection343, and the stone replacement operation portion344, so these components and members could also be easily maintained.

Among other things, the discharge pump35can be easily deteriorated or damaged as compared to other components. However, since the pump35can be easily maintained, the usability of the filtering device2can be dramatically improved.

In addition to the above, in the filtering device2of this first embodiment, the wood stone66of the protein skimmer6can be easily replaced. That is, the upper end portion of the inclined pipe64connected to the lower end portion of the skimmer main pipe61is opened at the upper surface of the upper wall member34of the functional component unit3, and the wood stone66with the air supply pipe65is inserted from the upper end opening portion of the inclined pipe64and placed at the specified position of the skimmer main pipe61. Therefore, by pulling out the air supplying pipe65from the upper end opening portion of the inclined pipe64, the wood stone66can be detached together with the air supplying pipe65. In this manner, the wood stone66can be easily detached and replaced with new one without removing the skimmer main pipe61and/or disassembling the other components. Especially, in the case of the wood stone66, although the exchanging timing is short due to clogging, the replacement of the wood stone66can be made easily. This further improves the usability of the filtering device2.

Furthermore, in the filtering device2of this first embodiment, the casing20is provided with the inlet chamber32so that the water W from the aquarium1can be once stored in the inlet chamber32and then supplied from this chamber32to the filtration zone Z2. This enables stable supply of water W to the filtration zone Z2, which in turn can improve the filtration capability.

Furthermore, in the filtering device2of this first embodiment, the inside of the casing20is open to the atmosphere and the upper portion of the casing20is in contact with air. Thus, filtering by aerobic filtering bacteria can be performed, which further improves the filtering capability.

Furthermore, in the filtering device2of this first embodiment, as the filtration materials71to73, filtering of different types is sequentially performed using wool or activated carbon for physical filtering, the bio ball for aerobic bacterial filtering, and Siporax for anaerobic bacterial filtering. Thus, the water W of the aquarium can be filtered assuredly and kept clean by the dry and wet method, which can keep the aquarium in the optimal environment for aquarium fish and the like.

In addition, in the filtering device2of this first embodiment, different types of filtration materials71to73are stacked to form the filtration zone Z2to cause the water W to pass through each of the filtration materials71to73sequentially from the upper one. Therefore, it is possible to assuredly pass the water W through each of the filtration materials71to73by gravity fall to thereby improve the filtering capability more assuredly.

Also, in the overflow device5of the aquarium system of this first embodiment, it is possible to avoid harmful effects to the peripheral environment caused by the suction sound occurring when the water W is sucked from the overflow pipe54. In a normal overflow pipe54, water and air are irregularly suctioned when the water W is suctioned from the upper end of the overflow pipe, generating the suction sound of air. In contrast, according to the overflow device5of this first embodiment, since the sound insulating cover57is mounted in the tank-outside water storage portion52so that the sound insulating cover57covers all of the four peripheral side surfaces and the upper surface of the above-water area of the periphery of the overflow pipe54. Therefore, even if the overflow pipe54generates suction sound, the suction sound is intercepted by the sound insulating cover57and trapped in the cover57. In this way, the suction sound is intercepted and prevented from spreading outside, so there are no harmful effects of the suction sound to the peripheral environment, and troubles caused by the suction sound can be assuredly prevented.

Second Embodiment

FIGS. 14 to 16show a water suction interception mechanism8of an overflow device5in an aquarium system according to a second embodiment of this invention. As shown in these drawings, the siphon pipe55and the discharge pipe56of this overflow device5are provided with suction holes555and556in the same manner as in the aforementioned embodiment. One end of the connection tube82is fluidly connected to the siphon side suction hole555via the pipe joint87, and the other end thereof is fluidly connected to the discharge side suction hole565via the pipe joint87.

In this second embodiment, different from the first embodiment, the suction pump80and suction tube81are not provided.

Furthermore, in the second embodiment, the connection tube82and the discharge pipe56constitute suction means, and the connection tube constitutes air introduction means.

In this second embodiment, the other structure is essentially the same as that of the first embodiment, and therefore the cumulative explanation will be omitted by allotting the same reference numeral to the same or corresponding portion.

In a normal state of this aquarium system according to the second embodiment, in the same manner as mentioned above, water W is circulating between the aquarium1and the filtering device2. In this normal state, flowing of the water W in the discharge pipe56gives a negative pressure in the connection tube82. Therefore, the suction function causes the water and/or the air (bubbles) in the siphon pipe55to be sucked in the discharge pipe56via the connection tube82.

During the normal operation, if the discharge pump35stops due to power failure, the water W in the discharge hose12flows backward. This causes the water W in the aquarium to be sucked in the discharge pipe56to start backward flow of water. However, as explained above, in this embodiment, air will be introduced into the discharge pipe56from the backflow preventing hole561formed in the discharge pipe56, which prevents the backward flow of the water W in the aquarium into the filtering device2.

Further introduction of air into the discharge pipe56causes the air to be introduced into the siphon pipe55via the backflow preventing hole561, the discharge pipe56and the connection tube82. The introduced air causes the water W in the siphon pipe55to be separated into the water W in the inlet side pipe portion of the siphon pipe55and the water W in the outlet side pipe portion thereof. This prevents the water W in the aquarium to be sucked into the siphon pipe55, resulting in immediate interception of the water supply by the siphon pipe55.

Also in this second embodiment, even if the discharge pump35suddenly stops due to, e.g., power failure, the backward flow of the water W in the aquarium to the outlet hose12can be prevented, and at the same time, the supply of the water W by the siphon pipe55can be automatically interrupted without delay.

Furthermore, in this second embodiment, even if the water supply by the siphon pipe55and the discharge pipe56is stopped due to power failure, when the power supply to the discharge pump35is resumed by the power recovery, the system returns to its normal state automatically.

In detail, when the discharge pump35is driven, the water in the filtering device2will be forcibly discharged into the aquarium via the outlet hole12and discharge pipe56. When the water flow is generated in the outlet hose12, a negative pressure will be given to the connection tube82from the side of the discharge pipe56. Accordingly, by this suction function, the air in the siphon pipe55will be sucked and discharged via the connection tube82. Thus, the air in the siphon pipe55is discharged, causing the water W in the aquarium to be sucked by the siphon pipe55and supplied to the filtering device2.

Furthermore, in the overflow device5of this second embodiment, without requiring a suction pump, in the same manner as in the first embodiment, unexpected sucking of water by the siphon pipe55and the discharge pipe56can be intercepted, and the system can be automatically recovered after power recovery. The elimination of a suction pump decreases the number of components, resulting in simplified structure and reduced cost.

In this second embodiment, except for the functions and effects mentioned above, the same functions and effects as in the first embodiment can be obtained.

Third Embodiment

FIGS. 17 to 19show a water suction interception mechanism8of an overflow device5in an aquarium system according to a third embodiment of this invention. As shown in these drawings, the siphon pipe55of this overflow device5is provided with a suction hole555in the same manner as mentioned above. To this suction hole555, in the same manner as in the first embodiment, a first connecting portion of the T-shaped pipe joint86is fluidly connected. Furthermore, connected to a second connecting portion of the pipe join86is one end of the suction tube81with the other end thereof connected to a suction pump80.

To a third connecting portion of the pipe joint86, one end of an air introduction tube83is fluidly connected. To the other end of this tube83, a control valve85is attached.

This control valve85is comprised of an electromagnetic valve which is configured to maintain its closed state when the power is turned on and turn to an open state when the power is turned off.

In the third embodiment, different from the aforementioned embodiments, no suction hole is formed in the discharge pipe56. The suction pipe56and the siphon pipe55are not communicated via the suction hole.

Furthermore, in the third embodiment, the suction pump80and the suction tube81constitute a suction means, and the air introduction tube83and the control valve85constitute an air introduction means.

In this third embodiment, the other structure is essentially the same as that of the aforementioned embodiments, and therefore the cumulative explanation will be omitted by allotting the same reference numeral to the same or corresponding portion.

In a normal state in the aquarium system of this third embodiment, in the same manner as mentioned above, water W is circulating between the aquarium1and the filtering device2. In its normal state, the driving of the suction pump80causes the water and/or air (bubbles) in the siphon pipe55to be sucked and discharged toward the suction pump80via the suction tube81.

In cases where the discharge pump35and the suction pump80stop due to power failure during the normal operation, the suction by the suction pipe80to the siphon pipe55is stopped and the control valve85is opened, causing outside air (air) to be introduced into the siphon pipe55via the control valve85and the air introduction tube83. The introduced air causes the water W in the siphon pipe55to be separated into the water W in the inlet side pipe portion of the siphon pipe55and the water W in the outlet side pipe portion thereof. This prevents the water W in the aquarium to be sucked into the siphon pipe55, resulting in immediate interception of the water supply by the siphon pipe55.

Also in this third embodiment, in the same manner as mentioned above, in cases where the discharge pump35stops, air will be introduced into the discharge pipe56from the backflow preventing hole561to prevent backward flow of the water W in the aquarium.

Also in this third embodiment, even if the discharge pump35suddenly stops due to, e.g., power failure, the backward flow of the water W in the aquarium to the outlet hose12can be prevented, and at the same time, the supply of the water W by the siphon pipe55can be automatically interrupted without delay.

Furthermore, also in this third embodiment, even if the water supply by the siphon pipe55and the discharge pipe56is stopped due to power failure, when the power supply to the discharge pump35, the suction pump80and the control valve85is resumed by the power recovery, the system returns to its normal state automatically.

In detail, when the discharge pump35is driven, the water in the filtering device2will be forcibly discharged into the aquarium via the outlet hole12and discharge pipe56. On the other hand, by driving the suction pump80, the air in the siphon pipe55will be sucked and discharged via the suction tube81. Thus, the air in the siphon pipe55is discharged, causing the water W in the aquarium to be sucked by the siphon pipe55and supplied to the filtering device2.

In this third embodiment, except for the functions and effects mentioned above, the same functions and effects as in the aforementioned embodiments can be obtained.

In the aforementioned embodiments, although the explanation was directed to the case in which the functional component unit3of the aquarium filtering device2includes the discharge pump35and the protein skimmer6, the present invention is not limited to it. In the present invention, it is not required that the functional component unit3includes the protein skimmer. Furthermore, the functional component unit3can include a heater, an air blower, a cooler or the like, for adjusting the water temperature.

In the overflow device5of the abovementioned embodiments, the tank-inside water storage portion51is provided in the aquarium1so that the water W in the aquarium is supplied to the tank-outside water storage portion52via the siphon pipe55, but the present invention is not limited to that. In the present invention, it is not always required to provide the tank-inside water storage portion. The inlet side end portion of the siphon pipe can be placed directly in the aquarium.

Also, in the abovementioned embodiments, although the explanation was directed to the case in which the present invention is applied to the overflow device in which the overflow pipe54is provided in the tank-outside water storage portion52, the present invention is not limited to it. The present invention can also be applied to an overflow device in which water W discharged from a filtration device is once stored in a water storage portion provided in the aquarium and then the water W is supplied from the water storage portion to the aquarium via an overflow pipe.

This application claims priority to Japanese Patent Application No. 2006-228892 filed on Aug. 25, 2006, the entire disclosure of which is incorporated herein by reference in its entirety.

It should be understood that the terms and expressions used herein are used for explanation and have no intention to be used to construe in a limited manner, and allow various modifications falling within the claimed scope of the present invention.

While illustrative embodiments of the invention have been described herein, the present invention is not limited to the various preferred embodiments described herein, but includes any and all embodiments having equivalent elements, modifications, omissions, combinations (e.g., of aspects across various embodiments), adaptations and/or alterations as would be appreciated by those in the art based on the present disclosure. The limitations in the claims are to be interpreted broadly based on the language employed in the claims and not limited to examples described in the present specification or during the prosecution of the application, which examples are to be construed as non-exclusive.

INDUSTRIAL APPLICABILITY

The aquarium overflow device according to the present invention can be used for an aquarium equipment for supplying water in an aquarium for aquarium fish, etc., to a filtering device, etc.