Patent Description:
As a small size of prefabricated and reusable liquid vessel, there has been known a vessel which has an inner circular member accommodated into an outer circular member such that the inner circular member has a lower end butted against a bottom member, and the outer circular member has a lower end fitted into an outer periphery of the bottom member (see <CIT>). Because this liquid vessel is configured in a prefabricated form, it is proposed to, even after having used the vessel as a vessel for an eating or drinking liquid or another item, reuse the liquid vessel by disassembling the vessel into the outer circular member, the inner circular member and the bottom member and washing the respective members, followed by assembling the members.

Nevertheless, in particular when a large size of liquid vessel is configured in a prefabricated form, many members are required to be assembled. For this reason, it is difficult to configure such a large size of liquid vessel in a prefabricated form because special measures are required to be taken to prevent a liquid from flowing out or leaking out through a gap between assembled members.

<CIT> discloses a large-capacity plastic tank comprising a peripheral wall formed of a plurality of elementary cells having the shape of a quadrangular bowl, obtainable by moulding. The outer face of the bottom of each cell is intended to constitute a fraction of the wall of the tank and the square walls are arranged to ensure, thanks to the use of suitable fixing means, the tight connection with the adjacent walls of neighbouring cells and with a suitable background.

<CIT> discloses a three-dimensional body produced by connecting a plurality of planar bodies.

<CIT> discloses a connection between curved segments of a wall of a liquid vessel ensuring a rotational degree of freedom.

The present invention provides a large size of liquid vessel which is capable of not only preventing a liquid held therein from flowing out or leaking out but also being configured in a prefabricated form. The present invention also provides a method for producing a glass product, which is as an effective utilization of the liquid vessel.

The present invention provides the following modes:.

According to the present invention, there is provided a prefabricated liquid vessel which is capable of not only preventing a liquid held therein from flowing out or leaking out but also being configured in a large size. According to the present invention, there is also provided a method for producing a glass product, which is as an effective utilization of the liquid vessel.

Embodiments of the present invention will be described in reference to the accompanying drawings. It should be noted that the present invention is not limited to the embodiments described below, and that various changes and modifications are made possible in an optional way within the scope of the present invention as defined in the appended claims. In the drawings referred to below, the scales, the numbers or the like of respective structures are shown in a different manner from those of actual structures in some cases in order to readily understand the respective structures.

As illustrated in <FIG>, the liquid vessel <NUM> according to this embodiment of the present invention includes a bottom portion <NUM> formed in a square shape, and a wall portion <NUM> formed in a square frame along an outer edge of the bottom portion <NUM>. The wall portion <NUM> extends so as to rise from the outer edge (periphery) of the bottom portion <NUM> in a depth direction of the liquid vessel <NUM>. The liquid vessel <NUM> is open on an opposite side of the bottom portion <NUM>. The liquid vessel <NUM> holds a liquid L in an inner space I defined by the bottom portion <NUM> and the wall portion <NUM>.

Specifically, the liquid vessel <NUM> is assembled from a plurality of first members <NUM>, a second member <NUM> and a plurality of third members <NUM>. The second member <NUM> is disposed in a central area of the bottom portion <NUM>. The first members <NUM> are engaged with the second member <NUM>. The third members <NUM> are engaged with the second member <NUM> and the first members <NUM>. With regard to the first members <NUM>, the second member <NUM> and the third members <NUM>, the peripheral edge of a main surface of each member is called an end portion. The engagement is made between facing end portions of the first members <NUM>, the second member <NUM> and the third members <NUM>.

As illustrated in <FIG>, each first member <NUM> includes a first joint portion <NUM> and a second joint portion <NUM>. The first joint portion <NUM> forms a part of the bottom portion <NUM> of the liquid vessel <NUM> (see <FIG>). The second joint portion <NUM> extends from an outer end portion 1101a of the first joint portion <NUM> so as to intersect the depth direction of the liquid vessel <NUM>. The second joint portion forms a part of the wall portion <NUM> (see <FIG>).

As illustrated in <FIG> and <FIG>, each first member <NUM> has third recessed portions <NUM> on respective sides. The first joint portion <NUM> of each first member <NUM> extends from the wall portion <NUM> of the liquid vessel <NUM> (see <FIG>) to the second member <NUM>. The first joint portion <NUM> has a first engageable projecting portion <NUM> formed on an end portion (hereinbelow, referred to as inner end portion) 1101b facing a central area of the liquid vessel <NUM>. The first engageable projecting portion <NUM> further includes a first projection <NUM> and a second recess <NUM>.

The first projection <NUM> has a pair of first projecting surfaces 111a and 111b. The second recess <NUM> has a pair of first recessed side surfaces 116a and 116b.

As illustrated in <FIG>, the second member <NUM> is disposed in the central area of the bottom portion <NUM> +& (see <FIG>). The first engageable projecting portion <NUM> of each first joint portion <NUM> is engaged with the second member <NUM>. The second member <NUM> has a base <NUM> and a plurality of second engageable recessed portions <NUM> formed on the periphery of the base <NUM>.

The second engageable recessed portions <NUM> are circumferentially disposed at equal intervals so as to radially project from an outer periphery of the base <NUM> toward an external space O of the liquid vessel <NUM>.

As illustrated in <FIG> and <FIG>, each second engageable recessed portion <NUM> includes a first recess <NUM> engageable with its corresponding first projection <NUM> and a pair of second projections <NUM> formed on the first recessed portion <NUM>. Each first recessed portion <NUM> has a pair of first recessed surfaces 125a and 125b. Each second projection <NUM> has a pair of projecting side surfaces 122a and 122b.

The first projection <NUM> of each first engageable projecting portion <NUM> is engaged with the first recess <NUM> of its corresponding second engageable recessed portion <NUM> to form a first engageable portion <NUM>.

Each first projection <NUM> is engaged with its corresponding first recessed portion <NUM> to form a first narrow space S1 defined by one 111a of its paired first projecting surfaces 111a and 111b, and one 125a of its corresponding paired first recessed surfaces 125a and 125b. Likewise, a first narrow space S2 is formed, being defined by the other one 111b of each pair of first projecting surfaces 111a and 111b, and the other one 125b of the corresponding paired first recessed surfaces 125a and 125b.

Thus, each first engageable portion <NUM> has a pair of the first narrow spaces S1 and S2. Each of the paired first narrow spaces S1 and S2 has a gap formed as a space that prevents the liquid L in the liquid vessel <NUM> from flowing out. In other words, the gap formed in each of the paired first narrow spaces S1 and S2 has a size that does not serve as a route allowing the liquid L to pass therethrough. This is also applicable to the narrow spaces described later.

In each pair of first narrow spaces S1 and S2, the gap is formed so as to extend in an engagement direction of its corresponding first member <NUM> and the second member <NUM> (directions indicated by an arrow A) and in an intersecting direction as viewed from a direction along a bottom surface (inner surface) 10a of the liquid vessel <NUM> (i.e. the depth direction of the liquid vessel <NUM>).

It is not essential that the gap of each pair of first narrow spaces S1 and S2 have a constant size. It is sufficient that the gap has a smaller size than a certain value. The gap may entirely or partly have a size varying from position to position. This is also applicable to the gaps of the other narrow spaces described later.

Each second recess <NUM> has its paired first recessed side surfaces 116a and 116b. Each second projecting portion <NUM> has its paired projecting side surfaces 122a and 122b. The second recess <NUM> of each first engageable projecting portion <NUM> is engaged with the second projecting portions <NUM> of its corresponding second engageable recess <NUM> to form a second engageable portion <NUM>.

Each second recess <NUM> is engaged with its corresponding second projecting portions <NUM> to form a second narrow space S3 defined by one 116a of its paired first recessed side surfaces 116a and 116b, and one 122a of its corresponding paired projecting side surfaces 122a and 122b. The other one 116b of each pair of first recessed side surfaces 116a and 116b is engaged with the other one 122b of its corresponding paired projecting side surfaces 122a and 122b to form a second narrow space S4.

In other words, each second engageable portion <NUM> has its paired second narrow spaces S3 and S4. Each of the second narrow spaces S3 and S4 has a gap formed as a space that prevents the liquid L in the liquid vessel <NUM> from flowing out. In each of the paired second narrow spaces S3 and S4, the gap is formed so as to extend in the engagement direction of its corresponding first member <NUM> and the second member <NUM> (directions indicated by an arrow A) and in the direction along the bottom surface (inner surface) 10a of the liquid vessel <NUM>.

Returning to <FIG> and <FIG>, the second member <NUM> and the first joint portion <NUM> of each first member <NUM> form a part of the bottom portion <NUM> of the liquid vessel <NUM> (see <FIG>) in a state wherein each first projection <NUM> is engaged with its corresponding first recess <NUM> while each second projection <NUM> is engaged with its corresponding second recess <NUM> (see <FIG> as well).

Each second joint portion <NUM> extends in a direction intersecting its corresponding first joint portion <NUM> (in other words, in the depth direction) such that each second joint portion <NUM> forms a part of the wall portion <NUM> of the liquid vessel <NUM> (see <FIG>).

Each third member <NUM> has a third projection <NUM> engaged with the third recessed portion <NUM> of its corresponding first member <NUM> and a third recess <NUM> of the second member <NUM>.

Each third member <NUM> has a first flat area <NUM> and a second flat area <NUM>. Further, each third member <NUM> has a third projection <NUM> engageable with the third recessed portion <NUM> of its corresponding first member <NUM> and the third recess <NUM> of the second member <NUM>.

As illustrated in <FIG> and <FIG>, the third recessed portion <NUM> of each first member <NUM> includes a pair of third recessed surfaces 117a and 117b. Each third projection <NUM> includes a pair of third projecting surfaces 133a and 133b.

Each third projection <NUM> is engaged with the first joint portion <NUM> of its corresponding first member <NUM> in a direction (directions indicated by an arrow B) intersecting the engagement direction of the first member <NUM> and the second member <NUM> (directions indicated by an arrow A).

Further, the third recess <NUM> of the second member <NUM> includes a pair of third recessed surfaces 127a and 127b. Each third projection <NUM> is engaged with the third recess <NUM> of the second member <NUM> in the direction (directions indicated by the arrow B) intersecting the engagement direction of the first member <NUM> and the second member <NUM> (directions indicated by an arrow A).

The second member <NUM> and each third projection <NUM> form a third engageable portion <NUM> such that each first joint portion <NUM> and the corresponding third projection <NUM> form a third engageable portion <NUM>.

Each third projection <NUM> is engaged with the third recessed portion <NUM> of its corresponding first member <NUM> (first joint portion <NUM>) to form a third narrow space S5 defined by the third projecting surface 133a of this third projection <NUM> and the third recessed surface 117a of this third recessed portion <NUM>. Likewise, a third narrow space S6 is formed, being defined by the third projecting surface 133b of this third projection <NUM> and the third recessed surface 117b of this third recessed portion <NUM>.

Each of the third narrow spaces S5 and S6 has a gap formed as a space that prevents the liquid L in the liquid vessel <NUM> from flowing out. In each of the third narrow spaces S5 and S6, the gap is formed so as to extend in a direction intersecting the engagement direction of its corresponding first member <NUM> and the second member <NUM> and in an intersecting direction (the depth direction of the liquid vessel <NUM>) seen from the direction along the bottom surface 10a of the liquid vessel <NUM>.

Each third projection <NUM> is engaged with the third recess <NUM> of the second member <NUM> to form a third narrow space S5 defined by the third projecting surface 133a of this third projection <NUM> and the third recessed surface 127a of this third recess <NUM>
as in the other portions of the third narrow space S5 formed by the other third projections <NUM> and the other first members <NUM>. The third projecting surface 133b of a third projecting portion <NUM> and the third recessed surface 127b of its corresponding third recessed portion <NUM> form a third narrow space S6 as in the other portions of the third narrow spaces S6 formed by the other third projections <NUM> and the other first members <NUM>.

As illustrated in <FIG> and <FIG>, the first members <NUM> and the second member <NUM> are combined so as to be brought into contact with each other. When the liquid vessel is subjected, for example, to deformation caused by an earthquake or to an installation error, a space P1 is formed between a leading edge 111c of each first projection <NUM> and a bottom 125c of each first recess <NUM> (see <FIG>).

In the first embodiment, each space P1 never communicates with the inner space I of the liquid vessel <NUM>. A leading edge 133c of each third projecting portion <NUM> and a bottom 117c of its corresponding third recessed portion <NUM> are combined so as to be brought into contact with each other. When the liquid vessel is subjected, for example, to deformation caused by an earthquake or to an installation error, a space P2 is formed between the combined leading edge and bottom. In the first embodiment, each space P2 never communicates with the external space O of the liquid vessel <NUM>. This is because measures are taken such that the liquid L that has entered in the space P1 is prevented from flowing into the space P2.

In other words, in the first embodiment, each second narrow space S3 is formed between its corresponding space P1 and its corresponding space P2, each second narrow space S3 is interposed between its corresponding first narrow space S1 and its corresponding third narrow space S5, and each first narrow space S1 and its corresponding third narrow space S5 communicate each other through its corresponding second narrow space S3.

In a case where there is a single engageable portion unlike the first embodiment, when engagement is shifted to form a space, this space serves as a liquid route. Further, when displacement is made in other directions than the engagement direction, a liquid route is generated because there is no degree of freedom in the deformation among members.

In a case where engagement is made at two locations unlike the first embodiment, when the engagement is shifted to form spaces, some of the spaces do not serves as a liquid route, although the other spaces serve as a liquid route. Further, when displacement is made in other directions than the engagement direction, a liquid route is generated because there is no degree of freedom in the deformation among members.

in contrast, in the first embodiment, when the first engageable portions and their corresponding second engageable portions are shifted to form spaces, some of the spaces do not serve as a liquid route, although the other spaces serve as a liquid route. Nevertheless, the provision of the third engageable portions blocks the liquid route in the other spaces to prevent a liquid from leaking outwardly. Further, the provision of the third engageable portions ensures a degree of freedom in the deformation among members with respect to the displacement of a first engageable portion and its corresponding second engageable portion in other directions than the engagement direction. Even when shifting is made in a direction toward or away from a third engageable portion to form a space, no liquid route is formed.

As described above, the provision of such sets of three engageable portions according to the embodiment of the present invention ensures not only a degree of freedom in a single engagement direction but also a degree of freedom in engagement directions intersecting the single engagement direction. Further, even when engagement is shifted to generate a space, no liquid route is formed from the inner space of the liquid vessel to the external space of the liquid vessel so long as the engagement is maintained.

In other words, even when external forces are generated in two directions by an earthquake or another external factor after installation of the liquid vessel <NUM>, the provision of such sets of three engageable portions according to the embodiment of the present invention causes nothing more than shifting among the first members <NUM>, the second member <NUM> and the third members <NUM>, and no liquid L leaks out so long as the engaged state of the combined members is maintained.

The provision of such sets of three engageable portions according to the embodiment of the present invention increases the tolerance to the installation accuracy in installation of the respective members because it is sufficient to pay attention only to the dimensional accuracy of the respective members.

It should be noted that the size of the spaces formed in the engageable portions may be defined by the lengths of the projections and the lengths of the recesses in the engageable portions in the engagement directions. From this point of view, it is sufficient to estimate how much shifting would occur in each engageable portion and to set the lengths of the projections and the lengths of the recesses in the engageable portions in the engagement directions to have greater lengths than the estimated shifting lengths so as to prevent disengagement.

Now, how to calculate the gap of each narrow space will be explained. In order to prevent the liquid L from leaking out, the following formula may be satisfied: <MAT> wherein the symbols in the formula indicate the following meanings:
GAP: the gap of each narrow space (first to third narrow spaces S1 to S6).

For example, when the liquid L is a molten metal of tin held in a liquid vessel <NUM> made of carbon, the allowable gap of each narrow space will be specified below. Here, the molten metal of tin has a depth set at <NUM>.

In this case, the molten metal of tin has a surface tension of <NUM> N/m and a contact angle of <NUM> degrees to carbon and a density of <NUM>,<NUM>/m<NUM>. Based on these values, it is sufficient that the gap of each narrow space is not greater than <NUM>. Conversely, even when there is a narrow space having a gap of about <NUM>, the molten metal of tin is prevented from flowing out.

For example, when the liquid L is molten glass held in a liquid vessel <NUM> made of carbon, the allowable gap of each narrow space will be specified below. Here, the molten glass has a depth set at <NUM>.

In this case, the molten glass has a surface tension of <NUM> N/m and a contact angle of <NUM> degrees to carbon and a density of <NUM>,<NUM>/m<NUM>. Based on these values, it is sufficient that the gap of each narrow space is not greater than <NUM>. Conversely, even when there is a narrow space having a gap of about <NUM>, the molten glass is prevented from flowing out.

For example, when the liquid L is water held in a liquid vessel <NUM> having water repellency, the allowable gap of each narrow space will be specified below. Here, the water has a depth set at <NUM>.

In this case, the water has a surface tension of <NUM> N/m and a contact angle of <NUM> degrees to the liquid vessel <NUM> having water repellency and a density of <NUM>,<NUM>/m<NUM>. Based on these values, it is sufficient that the gap of each narrow space is not greater than <NUM>.

It is possible to make up the liquid vessel <NUM> in a leakage-free manner by designing the respective narrow spaces as described above. Because it is not necessary to set the gap of each narrow space to zero as described above, and because it is sufficient to set the gap of each narrow space to not greater than a predetermined value, it is not necessary pay more attention than necessary on the production of the respective constituent members <NUM>, <NUM> and <NUM> of the liquid vessel <NUM> according to the present invention.

As described about the liquid vessel <NUM> according to the first embodiment, the liquid L is prevented from entering the respective narrow spaces by its surface tension.

In other words, even when the occurrence of deformation by an earthquake or an installation error causes a space P1 to be formed between a first member <NUM> and the second member <NUM> configured so as to be brought into contact with each other, and when the liquid L flows into the space P1, the provision of sets of a first narrow space S1, a second narrow space S3 and a third narrow space S5 can prevent the liquid from flowing out into their corresponding space P2. The inside of the liquid vessel <NUM> is made of the plurality of first members <NUM>, the second member <NUM> and the plurality of third members <NUM>. Thus, the liquid L can be prevented from flowing out from the inner space I of the liquid vessel to the external space O.

As describe above, the plurality of first members <NUM>, the second member <NUM> and the plurality of third members <NUM> can be all engaged as illustrated in <FIG> and <FIG> to easily make up the liquid vessel <NUM> in a large size of prefabricated form. It is impossible to produce the structure of such a liquid vessel by using of the method of laying bricks.

Specifically, the liquid vessel <NUM> can be assembled in a large size so as to have the bottom portion <NUM> formed in a square shape in a planar view and the wall portion <NUM> formed in a square frame along the outer edge of the bottom portion <NUM>.

The liquid vessel <NUM> can be made up in a large size of prefabricated form by a simple structure that each first member <NUM> is merely provided with a first engageable projecting portion <NUM> and a third recessed portion <NUM>, the second member <NUM> is merely provided with the second engageable recessed portions <NUM> and the third recessed portion <NUM>, and each third member <NUM> is merely provided with a third projecting portion <NUM>.

Further, the second member <NUM> is provided with the plurality of second engageable recessed portions <NUM>, and the first members <NUM> are engaged with the second engageable recessed portions <NUM>. Thus, the plurality of first members <NUM> are engaged with the single second member <NUM>. The number of the parts required for assembling the liquid vessel <NUM> can be minimized to simplify the structure.

The third members <NUM> are engaged with the first members <NUM> and the second member <NUM> to form the bottom portion <NUM> and the wall portion <NUM> of the liquid vessel <NUM> for example. Thus, the number of the parts required for assembling the liquid vessel <NUM> can be further minimized to simplify the structure.

Although explanation of the liquid vessel <NUM> according to the first embodiment has been made about a case where the first joint portion <NUM> of each first member <NUM> is provided with a first engageable projecting portion <NUM>, and the second member <NUM> is provided with the second engageable recessed portions <NUM>, the present invention is not limited to such a case. Conversely, the first joint portions <NUM> of the first members <NUM> may be interchanged with the second engageable recessed portions <NUM> of the second member <NUM> as another case.

With regard to the design of such sets of three engageable portions according to the embodiment of the present invention, each set of three engageable portions is formed to have a first narrow space, a second narrow space and a third narrow space formed without a large gap being formed between engaged members.

Now, first to seventh modifications of the first embodiment will be described in reference to <FIG>.

As illustrated in <FIG>, the liquid vessel <NUM> according to this modification is configured so as to have the same structure as the liquid vessel <NUM> according to the first embodiment except that the third members <NUM> are replaced with third members <NUM>.

Each third member <NUM> entirely has a uniform plate thickness T1. The plate thickness T1 is set to a thickness engageable with the third recessed portion <NUM> of a first member <NUM> to be engaged. In other words, each third member <NUM> has a plate thickness T1 equal to the thickness of each third projection <NUM>.

In this manner, the entire plate thickness T1 of the third members <NUM> can be reduced to a thickness equal to the thickness of each third projection <NUM>. Thus, the size of the plate thickness T1 of the third members <NUM> can be minimized to reduce the weight of the liquid vessel <NUM>.

As illustrated in <FIG>, the liquid vessel <NUM> according to this modification includes a plurality of first members <NUM>, a plurality of second members <NUM> and a plurality of third members <NUM>. Further, the liquid vessel <NUM> includes a fourth member <NUM>, a plurality of fifth members <NUM> and a plurality of sixth members <NUM>.

The fourth member <NUM> is disposed in a central area of a bottom portion of the liquid vessel <NUM> and is formed in a square shape in a planar view.

Each fifth member <NUM> is engaged mainly between its adjacent first members <NUM> as in the respective members <NUM>, <NUM> and <NUM> according to the first embodiment. The fifth members <NUM> are disposed at positions opposed to respective sides 34a to 34d of the fourth member <NUM>. Each fifth member <NUM> is formed in an L-character shape in a side view and includes a portion 35b forming a part of the bottom portion of the liquid vessel <NUM> and a portion 35a forming a part of a wall portion of the liquid vessel <NUM>.

Each sixth member <NUM> is engaged between its adjacent fifth member <NUM> and the fourth member <NUM> opposing each other and between its adjacent pair of second members <NUM> as in the respective members <NUM>, <NUM> and <NUM> according to the first embodiment. Each sixth member <NUM> forms a part of the bottom portion of the liquid vessel <NUM>.

The wall portion of the liquid vessel <NUM> is formed in a single layer and has a height of H1.

The fourth member <NUM> is disposed in a central area of the bottom portion of the liquid vessel <NUM>, and each fifth member <NUM> is engaged between its adjacent first members <NUM>. Thus, the respective sides of the liquid vessel <NUM> can have longer lengths L1 and L2 than the sides of the liquid vessel <NUM> according to the first embodiment. In other words, the second modification allows the liquid vessel <NUM> to be produced in a larger size of prefabricated form than the liquid vessel <NUM>.

Although explanation of the liquid vessel <NUM> according to the second modification has been made about a case where the wall portion of the liquid vessel <NUM> is formed in a single layer and have a height of H1, the liquid vessel is not limited to this mode. The wall portion of the liquid vessel <NUM> may have a plurality of stacked layers and a larger height H1.

As illustrated in <FIG>, the liquid vessel <NUM> according to this modification includes a plurality of first members <NUM>, a plurality of second members <NUM> and a plurality of third members <NUM>. In each first member <NUM>, the second joint portion <NUM> of each first member <NUM> according to the first embodiment (see <FIG>) is replaced with first joint portions <NUM>. In other words, each first member <NUM> is configured to have a pair of first joint portions <NUM> formed in an L-character shape in a side view.

Each third member <NUM> has an additional third projection (not shown) formed on sides corresponding to the opening sides of the third members <NUM> according to the first embodiment (see <FIG>). In other words, each third member has a third projection extending from all peripheral sides.

In the liquid vessel <NUM>, the plurality of first member <NUM>, the plurality of second member <NUM> and the plurality of third members <NUM> are engaged as in the respective members <NUM>, <NUM> and <NUM> according to the first embodiment. In this way, the plurality of first members <NUM>, the plurality of second members <NUM> and the plurality of third members <NUM> are engaged to form the liquid vessel <NUM> in a fully-closed state with no opening. In other words, the liquid vessel <NUM> is provided as a prefabricated liquid vessel wherein the opening opposite to the bottom portion of the liquid vessel <NUM> according to the first embodiment is closed.

As illustrated in <FIG>, the liquid vessel <NUM> according to this modification has a bottom portion <NUM> formed in a hexagonal shape and a wall portion <NUM> formed in a hexagonal frame along an outer edge (peripheral sides) of the bottom portion <NUM>.

The liquid vessel <NUM> has a plurality of first members <NUM>, a second member <NUM> and a plurality of third members <NUM>. In each first member <NUM>, the second joint portion <NUM> of each first member <NUM> according to the first embodiment (see <FIG>) is formed in a V-character shape in a planar view, and the remaining portions are formed in the same as those of each first member <NUM>.

The second member <NUM> is a member similar to the second member <NUM> according to the first embodiment (see <FIG>). The second member <NUM> has six second recessed projecting portions <NUM> radially projecting from a base <NUM> at equal intervals. Each first member <NUM> has a first joint portion <NUM> engaged with its corresponding second recessed projecting portion <NUM>, being brought into contact with this second recessed projecting portion as in the first embodiment.

Each third member <NUM> is disposed between its adjacent first members <NUM>. In each third member <NUM>, an area corresponding to the first flat area <NUM> of each third member <NUM> according to the first embodiment (see <FIG>) is formed in a triangular shape in a planar view, and the remaining portions are the same as those of each third member <NUM>. Each third member <NUM> is engaged with its adjacent first member <NUM> and the second member <NUM> as in the first embodiment.

As illustrated in <FIG>, the liquid vessel <NUM> according to this modification has a bottom portion <NUM> formed in an octagonal shape and a wall portion <NUM> formed in an octagonal frame along an outer edge (peripheral sides) of the bottom portion <NUM>. The liquid vessel <NUM> includes a plurality of first members <NUM>, a second member <NUM>, a plurality of third members <NUM> and a plurality of fourth members <NUM>.

In each first member <NUM>, a portion corresponding to the second joint portion <NUM> of each first member <NUM> according to the first embodiment (see <FIG>) is formed in a V-character shape in a planar view, and the remaining portions are formed in similar to those of each first portion <NUM>.

The second member <NUM> is disposed a central area of the bottom portion <NUM> of the liquid vessel <NUM> so as to be formed in an octagonal shape in a planar view. The plurality of fourth members <NUM> are engaged with peripheral sides of the second member <NUM>. Each first member <NUM> is engaged with its corresponding fourth member <NUM>, being brought into contact with this fourth member. Each third member <NUM> is engaged between its adjacent first members <NUM>.

The first members <NUM>, the second member <NUM>, the third members <NUM> and the fourth members <NUM> are engaged together as in the first members <NUM>, the second member <NUM> and the third members <NUM> according to the first member to produce a prefabricated liquid vessel.

As illustrated in <FIG>, the liquid vessel <NUM> according to this modification has a bottom portion <NUM> formed in a circular shape and a wall portion <NUM> formed in a cylindrical shape along an outer edge (peripheral side) of the bottom portion <NUM>. The liquid vessel <NUM> includes a plurality of first members <NUM>, a second member <NUM> and third members <NUM>.

In each first member <NUM>, the second joint portion <NUM> of each first member <NUM> according to the first embodiment (see <FIG>) is formed in a curved shape in a planar view.

The second member <NUM> is disposed in an central area of the bottom portion <NUM> of the liquid vessel <NUM>. The first members <NUM> are engaged with the second member <NUM>, being brought into contact with the second member. Each third member <NUM> is engaged between its adjacent first members <NUM>. In each third member <NUM>, the second flat area <NUM> of each third member <NUM> according to the first embodiment (see <FIG>) is formed in an arc-shape in a planar view.

The first members <NUM>, the second member <NUM> and the third members <NUM> are engaged together as in the first members <NUM>, the second member <NUM> and the third member <NUM> according to the first embodiment to produce a prefabricated liquid vessel.

As described above, each of the liquid vessels <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> and <NUM> according to the first embodiment and the first to sixth modifications allows the bottom portion to be formed in a polygonal shape and the wall portion to be formed in a polygonal frame along the out edge (peripheral sides) of the bottom portion. Thus, the shape of the liquid vessel can be selected according to applications of the liquid vessel to expand the applications of the liquid vessel.

Now, the liquid vessels <NUM> and <NUM> according to a second embodiment and a third embodiment will be described in reference to <FIG> and <FIG>.

As illustrated in <FIG>, the liquid vessel <NUM> according to this embodiment is made up by a bottom portion <NUM> formed in a square shape and a wall portion <NUM> formed in a square frame along an outer edge (peripheral sides) of the bottom portion <NUM>. Further, the liquid vessel <NUM> is opened on an opposite side of the bottom portion <NUM>. The liquid vessel <NUM> is configured so as to hold a liquid L in an inner space I defined by the bottom portion <NUM> and the wall portion <NUM>.

Specifically, the liquid vessel <NUM> is assembled from a plurality of first members <NUM>, a second member <NUM> and a plurality of third members <NUM>. The second member <NUM> is disposed in a central area of the bottom portion <NUM>. The plurality of first members <NUM> are engaged with the second member <NUM>. Each third member <NUM> is engaged with its adjacent first members <NUM> and the second member <NUM>.

As illustrated in <FIG>, each first member <NUM> includes a first joint portion <NUM> and a second joint portion <NUM>. The first joint portion <NUM> forms a part of the bottom <NUM> of the liquid vessel <NUM> (see <FIG>). The second joint portion <NUM> extends from an outer end portion 8101a of the first joint portion <NUM> to a depth direction of the liquid vessel <NUM>. The second joint portion <NUM> of each first member forms a part of the wall portion <NUM>.

As illustrated in <FIG> and <FIG>, each first joint portion <NUM> includes a first inner joint surface 8101c, a first outer joint surface 8101d and a pair of first side joint surfaces 8101e. Each first inner joint surface 8101c is disposed on a side of the inner space I of the liquid vessel <NUM>. Each first outer joint surface 8101d is disposed on a side of an external space O of the liquid vessel <NUM>. One of paired first side joint surfaces 8101e is disposed to connect between one of both sides of the first inner joint surface 8101c and one of both sides of the first outer joint surface 8101d. The other one of the paired first side point surfaces 8101e is disposed to connect between the other side of the first inner joint surface 8101c and the other side of the first outer joint surface 8101d.

Each first joint portion <NUM> is formed in a rectangular shape in section by its first inner joint surface 8101c, first outer joint surface 8101d and paired first side joint surfaces 8101e.

Each joint portion <NUM> extends from the wall portion <NUM> of the liquid vessel <NUM> (see <FIG>) to the second member <NUM>. Each first joint portion <NUM> includes a first engageable projecting portion <NUM> formed on an end portion (hereinbelow, referred to as inner end portion) 8101b close to a central side of the liquid vessel <NUM>. Each first engageable projecting portion <NUM> is provided with a first projection <NUM> and a second projection <NUM>.

Each first projection <NUM> is formed in a rectangular shape in section and projects toward a central area side of the liquid vessel <NUM> in a direction along a bottom surface (inner surface) 80a of the liquid vessel <NUM>.

Each second projection <NUM> is formed on a side of a bottom surface 80a of the liquid vessel <NUM> with respect to its corresponding first projection <NUM>. Each second projection <NUM> projects toward the central area side of the liquid vessel <NUM> in the direction along the bottom surface 80a of the liquid vessel <NUM>.

Returning to <FIG>, each first joint portion <NUM> has a second joint portion <NUM> formed on an outer end portion (opposite end portion) 8101a of its corresponding first engageable projecting portion <NUM>. Each second joint portion <NUM> extends in a direction intersecting its corresponding first joint portion <NUM> (in other words, a depth direction of the liquid vessel <NUM>). The second joint portions <NUM> are formed in a rectangular shape in section as in the first joint portions <NUM>.

The second member <NUM> is disposed at a central portion of the bottom portion <NUM> (see <FIG>). The first engageable projecting portion <NUM> of each first joint portion <NUM> is engaged with the second member <NUM>. The second member <NUM> includes a base <NUM> forming the central portion and a plurality of second engageable recessed portions <NUM> formed the periphery of the base <NUM>.

The second engageable recessed portions <NUM> are disposed at four positions on the outer periphery of the base <NUM>. In other words, the second engageable recessed portions <NUM> are circumferentially disposed at equal intervals so as to radially project from the outer periphery of the base <NUM> toward an external space O of the liquid vessel <NUM>. Each second engageable recessed portion <NUM> includes a first recess <NUM> engageable with its corresponding first projection <NUM> and a second recess <NUM> formed at the first recess <NUM>.

As illustrated in <FIG> and <FIG>, each second engageable portion <NUM> includes a first inner engageable surface 8210a, a first outer engageable surface 8210b and a pair of first engageable side surfaces 8210c. Each first inner engageable surface 8210a is disposed on a side of the inner space I of the liquid vessel <NUM>. Each first outer engageable surface 8210b is disposed on a side of the external space O of the liquid vessel <NUM>. One of paired first engageable side surfaces 8210c is disposed to connect between one side of its corresponding first inner engageable surface 8210a and one side of its corresponding outer engageable surface 8210b. The other one of paired first engageable side surfaces 8210c is disposed to connect between the other side of its corresponding first inner engageable surface 8210a and the other side of its corresponding first outer engageable surface 8210b.

Each second engageable recessed portion <NUM> has an outer shape formed in a rectangular shape in section by its corresponding first inner engageable surface 8210a, first outer engageable surface 8210b and paired first engageable side surfaces 8210c.

Each first recess <NUM> is open so as to be engageable with its corresponding first projection <NUM>. Each second recess <NUM> is formed in a part of its corresponding second engageable recessed portion <NUM> close to the bottom surface 80a of the liquid vessel <NUM> and is formed in a groove shape so as to be engageable with its corresponding second projection <NUM>.

Each first projection <NUM> is engaged with its corresponding first recess <NUM> to form a first engageable portion <NUM>. Each second projection <NUM> is engaged with its corresponding second recess <NUM> to form a second engageable portion <NUM>.

The first projections <NUM> are engaged with the first recesses <NUM>, and the second projections <NUM> are engaged with the second recesses <NUM>, causing the first joint portions <NUM> to radially extend from the second member <NUM>.

As illustrated in <FIG>, the first inner joint surface 8101c of each first joint portion <NUM> and the first inner engageable surface 8210a of its corresponding second engageable recessed portion <NUM> are disposed to be flush with each other. The first outer joint surface 8101d of each first joint portion <NUM> and the first outer engageable surface 8210b of its corresponding second engageable recessed portion <NUM> are disposed to be flush with each other.

Each first projecting portion <NUM> includes a pair of first projecting surfaces 811a and 811b. Each first recess <NUM> includes a pair of first recessed surfaces 825a and 825b. Each first projecting portion <NUM> is engaged with its corresponding first recess <NUM> to form a first narrow space S7 defined by one 811a of its paired first projecting surfaces 811a and 811b and one 825a of its corresponding paired first recessed surfaces 825a and 825b. The other one 811b of the paired first projecting surfaces 811a and 811b and its corresponding paired first recessed surfaces 825a and 825b form a first narrow space S8.

Thus, each first engageable portion <NUM> includes a pair of first narrow spaces S7 and S8. Each of paired first narrow spaces S7 and S8 has a gap formed as a space that prevents the liquid L in the liquid vessel <NUM> from flowing out. In other words, each of the first narrow spaces S7 and S8 is formed to have such a gap that the liquid L is prevented from entering each of the first narrow spaces S7 and S8 by surface tension.

In each of the paired first narrow spaces S7 and S8, the gap is formed so as to extend in an engagement direction of the first members <NUM> and the second member <NUM> (directions indicated by an arrow A) and in an intersecting direction as viewed from a direction along the bottom surface (inner surface) 80a of the liquid vessel <NUM> (i.e. the depth direction of the liquid vessel <NUM>).

Returning to <FIG>, each second projecting portion <NUM> has a pair of second projecting side surfaces 812a and 812b. Each second recess <NUM> includes a pair of second recessed side surfaces 826a and 826b. Each second projecting portion <NUM> is engaged with its corresponding second recess <NUM> to form a second narrow space S9 defined by one 812a of its paired second projecting side surfaces 812a and 812b and one 826a of its corresponding paired second recessed side surfaces 826a and 826b. The other one 812b of paired second projecting side surfaces 812a and 812b and the other one 826b of its corresponding paired second recessed side surfaces 826a and 826b form a second narrow space S10.

Thus, each second engageable portion <NUM> includes a pair of second narrow spaces S9 and S10. Each of the paired second narrow spaces S9 and S10 has a gap formed as a space that prevents the liquid L in the liquid vessel <NUM> from flowing out. In other words, each of the paired second narrow spaces S9 and S10 is formed so as to have a gap sized to prevent the liquid L from entering their corresponding first narrow spaces S7, S8 by surface tension. In each of the paired second narrow spaces S9 and S10, the gap is formed so as to extend in the engagement direction of the first members <NUM> and the second member <NUM> and in the direction along the bottom surface (inner surface) 80a of the liquid vessel <NUM>.

As illustrated in <FIG>, each third member <NUM> includes a first flat area <NUM> and a second flat area <NUM>. Each first flat area <NUM> is formed in a rectangular shape in a planar view and forms a part of the bottom portion <NUM> of the liquid vessel <NUM> (see <FIG>). Each second flat area <NUM> is bent in an L-character shape along an outer edge (peripheral side) of its corresponding first flat area <NUM> in a planar view and forms a part of the wall portion <NUM> of the liquid vessel <NUM> (see <FIG>).

Further, each third member <NUM> includes third recessed portions <NUM> engageable with its adjacent first members <NUM> and its adjacent second member <NUM>. Each third recessed portion <NUM> has a third bottom recessed portion <NUM> formed at the first flat area <NUM> and a third wall recessed portion 837V formed at the second flat area <NUM>.

Each third bottom recessed portion <NUM> is formed in a recessed shape in section so as to be engageable with the first joint portion <NUM> of its adjacent first member <NUM> and the second member <NUM>. Each third wall recessed portion 837V is formed in recessed shape in section so as to be engageable with the second joint portion <NUM> of its adjacent first member <NUM>.

Specifically, each third member <NUM> is engaged with third projecting portions <NUM> and <NUM> formed at lateral positions of its adjacent first members <NUM> and the second member <NUM>, being brought into contact with these third projecting portions in a direction (directions indicated by an arrow B) intersecting the engagement direction of this adjacent first member <NUM> and the second member <NUM> (directions indicated by an arrow A).

Each third member <NUM> is engaged with its adjacent first member <NUM> in such a state that the plurality of first members <NUM> are engaged with the second member <NUM>.

As illustrated in <FIG> and <FIG>, each third bottom recessed portion <NUM> is formed in a recessed shape in section and includes a third inner bottom recessed surface 837Ha and a third outer bottom recessed surface 837Hb. The third inner bottom recessed surfaces 837Ha and the third outer bottom recessed surfaces 837Hb are formed along the bottom surface 80a of the liquid vessel <NUM>.

Each third bottom recessed portion H is engaged with the first joint portion <NUM> of its adjacent first member <NUM> in a direction (directions indicated by an arrow B) intersecting an engagement direction of its adjacent first member <NUM> and the second member <NUM> (directions indicated by an arrow A). Each first joint portion <NUM> and its corresponding third bottom recessed portion <NUM> form a third engageable portion <NUM>. Further, each third bottom recessed portion <NUM> is engaged with the second member <NUM> in a direction (directions indicated by an arrow B) intersecting the engagement direction of its adjacent first member <NUM> and the second member <NUM> (directions indicated by the arrow A). The second member <NUM> and each third bottom recessed portion <NUM> form a third engageable portion <NUM>.

Each third bottom recessed portion <NUM> is engaged with the first joint portion <NUM> of its adjacent first member <NUM> to form a third narrow space S11 defined by its third inner bottom recessed surface 837Ha and the first inner joint surface 8101c of this first joint portion <NUM>. Each third outer bottom recessed surface 837Hb and the first outer joint surface 8101d of its corresponding first joint portion <NUM> form a third narrow space S12.

Further, each third bottom recessed portion <NUM> is engaged with the second member <NUM> to form a third narrow space S11 defined by its third inner bottom recessed surface 837Ha and the first inner engageable surface 8210a of its corresponding first joint portion <NUM>. Each third outer bottom recessed surface 837Hb and the first outer engageable surface 8210b of its corresponding first joint portion <NUM> form a third narrow space S12. In each of the third narrow spaces S11 and S12, the gap is formed as a space that prevents the liquid L in the liquid vessel <NUM> from flowing out. In each of the third narrow spaces S11 and S12, the gap is formed so as to extend in a direction intersecting the engagement direction of the first members <NUM> and the second member <NUM> and in an intersecting direction as viewed from the direction along the bottom surface 80a of the liquid vessel <NUM> (the depth direction of the liquid vessel <NUM>).

As illustrated in <FIG> and <FIG>, the third recessed all portion 837V of each second flat area <NUM> is engaged with the second joint portion <NUM> of its adjacent first member <NUM> to form a third narrow space S13 and a third narrow space S14. Each third narrow space S13 is continuous to its corresponding third narrow space S11 (see <FIG>). Each third narrow space S14 is continuous to its corresponding third narrow space S12 (see <FIG>).

Each of the third narrow spaces S13 and S14 has a gap formed as a space that prevents the liquid L in the liquid vessel <NUM> from flowing out. In other words, each of the third narrow spaces S13 and S14 has a gap to prevent the liquid L from entering its corresponding narrow spaces S7 and S8 based on the relationship between the surface tension and the contact angle of the liquid.

As illustrated in <FIG> and <FIG>, the first projecting surface 811a of each first projecting portion <NUM> and the first recessed surface 825a of its corresponding first recess <NUM> form a first narrow space S7 on a side of the bottom surface 80a of the liquid vessel <NUM>. The second projecting side surface 812a of each second projecting portion <NUM> and the second recessed side surface 826a of its corresponding second recess <NUM> form a second narrow space S9 on the side of the bottom surface 80a of the liquid vessel <NUM>. The first engageable inner surface 8210a of each second engageable recessed portion <NUM> and the third inner bottom recessed surface 837Ha of its corresponding third bottom recessed portion <NUM> form a third narrow space S11 on the side of the bottom surface 80a of the liquid vessel <NUM>.

Each second narrow space S9 is interposed between its adjacent first narrow space S7 on the side of the bottom surface 80a and its adjacent third narrow space S11 on the side of the bottom surface 80a, and each first narrow space S7 on the side of the bottom surface 80a is continuous to its adjacent third narrow space S11 on the side of the bottom surface 80a through their adjacent second narrow space S9.

Each first member <NUM> and the second member <NUM> are brought into contact with each other so as to form a space P3 and a space P4 at their first engageable portion <NUM> and their second engageable portion <NUM> when the liquid vessel is subjected, for example, to deformation caused by an earthquake or to an installation error. The first flat area <NUM> of one of adjacent third members <NUM> and the first flat area <NUM> of the other one of these adjacent third members <NUM> are brought into contact with each other so as to form a space P5a between these adjacent third members <NUM> brought into contact with each other, when the liquid vessel is subjected, for example, to deformation caused by an earthquake or to an installation error.

Further, each first member <NUM> and its adjacent third member <NUM> are brought into contact with each other so as to form a space P5b when the liquid vessel is subjected, for example, to deformation caused by an earthquake or to an installation error.

In the second embodiment, each space P4 never communicates with the external space O of the liquid vessel <NUM>. In the second embodiment, the space P3 between each second projecting portion <NUM> and its corresponding second recess <NUM> never communicates with the space P5a between the first flat areas <NUM> and <NUM> on both sides of its corresponding first joint portion <NUM>. This is because measures are taken such that the liquid L that has entered in each space P3 is prevented from flowing into its corresponding space P4.

In other words, in the second embodiment, sets of a first narrow space S7, a second space S9 and a third space S11 are provided. Thus, such sets of a first narrow space S7, a second space S9 and a third space S11 avoid that the liquid L that flows into the spaces P3 from their corresponding spaces P5a flows into the spaces P4.

The plurality of first members <NUM>, the second member <NUM> and the plurality of third members <NUM> can be all engaged as illustrated in <FIG> and <FIG> to easily make up the liquid vessel <NUM> in a large size of prefabricated form.

Specifically, the liquid vessel <NUM> can be assembled in a large size so as to have the bottom portion <NUM> formed in a square shape in a planar view and the wall portion <NUM> formed in a square frame along the bottom portion <NUM>.

The liquid vessel <NUM> can be made up in a large size of prefabricated form by a simple structure that each first member <NUM> is merely provided with a first projecting portion <NUM> and a second projecting portion <NUM>, the second member <NUM> is merely provided with the first recesses <NUM> and the second recesses <NUM>, and each third member <NUM> is merely provided with a third recessed portion <NUM>.

Further, the second member <NUM> is provided with a plurality of second engageable recessed portions <NUM>, and the first members <NUM> are engaged with the second engageable recessed portions <NUM>. Thus, the plurality of first members <NUM> are engaged with the single second member <NUM>. The number of the parts required for assembling the liquid vessel <NUM> can be minimized to simplify the structure.

Although explanation of the liquid vessel <NUM> according to the second embodiment has been made about a case where the first joint portion <NUM> of each first member <NUM> is provided with a first engageable projecting portion <NUM>, and the second member <NUM> is provided with the second engageable recessed portions <NUM>, the present invention is not limited to such a case. As another case, each first joint portion <NUM> may be provided with a second engageable recessed portion <NUM>, and the second member <NUM> may be provided with first engageable projecting portions <NUM>.

As illustrated in <FIG> and <FIG>, the liquid vessel <NUM> according to this embodiment of the present invention includes a bottom portion <NUM> formed in a square shape, and a wall portion <NUM> formed in a square frame along an outer edge (peripheral sides) of the bottom portion <NUM>. The liquid vessel <NUM> is open on an opposite side of the bottom portion <NUM>. The liquid vessel <NUM> is configured to hold a liquid L in an inner space I defined by the bottom portion <NUM> and the wall portion <NUM>.

Specifically, the liquid vessel <NUM> is assembled from a first member <NUM>, a second member <NUM> and a pair of third members 93A and 93B.

Explanation will be made, the engagement direction of the first member <NUM> and the second member <NUM> being called directions indicated by an arrow A, and directions orthogonal to the directions indicated by the arrow A being called directions indicated by an arrow B.

The first member <NUM> is disposed at a central position of the liquid vessel <NUM> in the directions indicated by the arrow B and on one side in the directions indicated by the arrow A. The second member <NUM> is disposed at a central position of the liquid vessel <NUM> in the directions indicated by the arrow B and on the other side in the directions indicated by the arrow A. Each of the first member <NUM> and the second member <NUM> is formed in an L-character shape in a side view. The first member <NUM> has a leading edge portion 911a engaged with a leading edge portion 922a of the second member <NUM>. The first member <NUM> has a third recessed portion <NUM> formed at one of lateral sides while the second member <NUM> has a third recessed portion <NUM> formed at one of lateral sides. The first member <NUM> has a third projecting portion <NUM> formed on the other lateral side while the second member <NUM> has a third projecting portion <NUM> formed at the other lateral side.

The third member 93A has third projecting portions <NUM> engaged with the third recessed portions <NUM> and <NUM> to form one 903A of third engageable portions. The third member 93B has a third recessed portion <NUM> engaged with the third projecting portions <NUM> and <NUM> to form the other 903B of the third engageable portions.

As illustrated in <FIG>, <FIG>, the first member <NUM> has a first projecting portion <NUM> engaged with a first recessed portion <NUM> of the second member <NUM> to form a first engageable portion <NUM>. The first projecting portion <NUM> has projecting side surfaces, one 911a of which forms a fourth narrow space S15 along with its corresponding one 925a of recessed side surfaces of the first recessed portion <NUM>. The other projecting side surface 911b of the first projecting portion <NUM> forms a fourth narrow space S16 along with the other recessed side surface 925b of the first recessed portion <NUM>.

Each of the fourth narrow spaces S15 and S16 has a gap formed as a space that prevents the liquid L in the liquid vessel <NUM> from flowing out.

The first member <NUM> has a second projecting portion <NUM> engaged with a second recess <NUM> of the second member <NUM> to form a second engageable portion <NUM>. The second projecting portion <NUM> has a projecting side surface 912a, which forms a second narrow space S17 along with a recessed side surface 926a of the second recess <NUM>. The second narrow space S17 has a gap formed as a space that prevents the liquid L in the liquid vessel <NUM> from flowing out.

The third member 93B has a third recessed portion <NUM>, which has a recessed surface 937a to form a third narrow space S18 along with a projecting surface <NUM> on the other side of the second member <NUM>. The third narrow space S18 has a gap formed as a space that prevents the liquid L in the liquid vessel <NUM> from flowing out.

Further, the first member <NUM> has a fourth projecting portion <NUM> engaged with a fourth recessed portion <NUM> of the second member <NUM> to form a fourth engageable portion <NUM>. The fourth projecting portion <NUM> has a recessed surface 928a, which forms a first narrow space S19 along with a projecting surface 914a of the fourth projecting portion <NUM>. The first narrow space S19 has a gap formed as a space that prevents the liquid L in the liquid vessel <NUM> from flowing out.

The second narrow space S17 is interposed between the first narrow space S19 and the third narrow space S18, and the first narrow space S19 is continuous to the third narrow space S18 through the second narrow space S17.

Thus, the liquid L that flows into a space P6 is prevented from flowing into a space P8 through a space P8 by the first narrow space S19, the second narrow space S17 and the third narrow space S18.

As illustrated in <FIG>, in the one 903A of the third engageable portions, the third projecting portion <NUM> is engaged with the third recessed portions <NUM> and <NUM>. A recessed surface 917a of the third recessed portion <NUM> and a recessed surface 927a of the third recessed portion <NUM> form one of third narrow spaces S20.

The one of the third narrow spaces S20 has a gap formed as a space that prevents the liquid L in the liquid vessel <NUM> from flowing out. Thus, the liquid L that flows into a space P9 is prevented from flowing into a space P10 by the third narrow portion S20.

In the other third engageable portion 903B, the third recessed portion <NUM> is engaged with the third projecting portion <NUM> of the first member <NUM> and the third projecting portion <NUM> of the second member <NUM>. A recessed surface 937a of the third recessed portion <NUM>, a projecting surface 913a of the third projecting portion <NUM> and a projecting surface 923a of the third projecting portion <NUM> form other third narrow space S21.

The other third narrow space S21 has a gap formed as a space that prevents the liquid L in the liquid vessel <NUM> from flowing out. The liquid vessel <NUM> has an inner side defined by the first member <NUM>, the second member <NUM> and the paired third members 93A and 93B. Thus, the liquid L that flows into a space P11 is prevented from flowing into a space P12 by the other third narrow portion S21.

Thus, the first member <NUM>, the second member <NUM> and the paired third members 93A and 93B can be all engaged as illustrated in <FIG> to easily make up the liquid vessel <NUM> in a large size of prefabricated form.

The liquid vessel according to the present invention is applicable to a vessel for holding various kinds of liquids in a wide range of fields. As a preferred example, the liquid vessel is usable as a molten metal bath for glass product production, which holds a liquid, such as molten metal for producing glass products, such as glass plates, by a float process, for example, disclosed in <CIT>. In the molten metal bath used in a float process, for example, molten metal, specifically molten tin, is held as the liquid L.

As another example, the liquid vessel is applicable to a bath for holding molten glass for producing glass products. As the bath for holding molten glass, the liquid vessel is applicable to a refiner for removing bubbles in molten glass after melding glass materials, a canal for forming molten glass by a down-draw process, or a forming apparatus called sword. Further, the liquid vessel according to the present invention may be used in the method for producing glass products such that a molten metal bath, a canal, a sword or the like that has been used in conventional glass production equipment is replaced by the vessel structure according to the present invention.

Claim 1:
A liquid vessel (<NUM>) for holding a liquid, comprising:
at least a first member (<NUM>), a second member (<NUM>) and a third member (<NUM>); and
a first engageable portion (<NUM>) and a second engageable portion (<NUM>) being configured such that the first member (<NUM>) and the second member (<NUM>) are brought into contact with each other to be engaged, and a third engageable portion (<NUM>) being configured such that the third member (<NUM>) is brought into contact with the first member (<NUM>) and the second member (<NUM>) in a direction intersecting an engagement direction of the first member (<NUM>) and the second member (<NUM>) to be engaged with the first member (<NUM>) and the second member (<NUM>);
wherein the liquid vessel (<NUM>) includes a wall portion (<NUM>), the wall portion (<NUM>) having an inner side defined by at least the third member (<NUM>), the wall portion (<NUM>) extending in a depth direction of the liquid vessel (<NUM>) from a bottom portion (<NUM>) of the liquid vessel (<NUM>) and a periphery of the bottom portion (<NUM>);
characterised in that:
the first engageable portion (<NUM>) and the second engageable portion (<NUM>) ensure a degree of freedom in the engagement direction of the first and second engageable portions,
the third engageable portion (<NUM>) ensures a degree of freedom in the engagement direction intersecting to the engagement direction of the first and second engageable portions,
the first engageable portion (<NUM>) includes a first narrow space (S1, S2), which has a gap formed in the engagement direction of the first member (<NUM>) and the second member (<NUM>) and in the depth direction of the liquid vessel (<NUM>);
the second engageable portion (<NUM>) includes a second narrow space (S3, S4), which has a gap formed in the engagement direction of the first member (<NUM>) and the second member (<NUM>) and in the direction along a bottom surface of the liquid vessel (<NUM>);
the third engageable portion (<NUM>) includes a third narrow space (S5, S6), which has a gap formed in a direction intersecting the engagement direction of the first member (<NUM>) and the second member (<NUM>) and in the depth direction of the liquid vessel (<NUM>);
the second narrow space (S3, S4) is interposed between the first narrow space (S1, S2) and the third narrow space (S5, S6), and the first narrow space (S1, S2) and the third narrow space (S5, S6) are continuous to each other through the second narrow space (S3, S4).