Technical Field

The present invention is related to the structural characteristics of a cistern tank for concealed cistern systems.

Prior Art

In general, water tanks of concealed cistern systems are manufactured from plastic materials, and by various methods of manufacturing. One of the plastic injection or blow molding methods is commonly preferred in the manufacture of plastic tanks.

In case the blow molding method is the preferred manufacturing method, the cistern tank may be manufactured to have an inspection opening, and a one-piece structure. However, the plastic injection method, which offers more stability, is more widely preferred over the blow molding method due to various requirements and difficulties implied by the blow molding process.

However, when the overall design characteristics of cistern tanks are considered, it is understood that manufacturing a cistern tank with a one-piece structure by using plastic injection molding techniques is unlikely.

Therefore, cistern tanks are manufactured in two pieces by means of plastic injection molding method and assembled in the assembly step.

An important measure to be considered in designing a cistern tank in two pieces is the water level inside the cistern tank. The volume of the cistern tank is divided into two in terms of design at a safer level located above the potential maximum water level inside the cistern tank.

Access openings of cistern tanks are positioned at a level that is higher than the maximum water level of the cistern tank. The line that separates the cistern tank into two parts is usually created at a level range located around the lower portion of the access opening.

Once the structural implementation of the concealed cistern is complete, an access canal is joined with the cistern tank to be able to access the components of the hardware inside the cistern tank through an access opening when the system is located inside a wall or behind a panel. Various methods including screw/bolt connections or snap-fit connections may be used in order to effect said joint.

The patent document numbered EP0916775 discloses a cistern tank that may be manufactured by means of blow molding method.

The patent document numbered EP1172490 focuses on an application that relates to dividing a cistern tank into two parts. In said application, the entire access opening is created inside the upper part of the tank. The line that divides the cistern tank into two parts begins at a level below the access opening.

The patent document numbered EP 1647638 focuses on the relations between the cistern tank that is divided into two parts and the access hole. Said document discloses the mounting of the access canal at various positions by using screws. In the same document, although it is not the main focus of the document, the application that relates to dividing the cistern tank into two parts is illustrated by visuals.

The patent document numbered EP1918467 focuses on joining an access canal with a tank. A screw joint is described in the application.

The patent document numbered EP1936048 discloses an application in which the cistern tank is formed in two parts and the entire access opening is created in the lower part of the cistern tank.

In most cistern tank applications for concealed cistern systems available in the state of the art, the cistern tank usually has a line of separation that generally runs either at the lower or about the middle section of the access opening of the cistern tank. Concealed cistern systems comprising such tanks are capable of tolerating certain levels of pressure under the plaster and wall layers of the construction application based on the proper implementation thereof. Accordingly, local contractions occur due to the stretching of the cistern tank towards the inner volume. As a natural consequence, operation of the cistern hardware located inside the tank may be affected and various assembly/disassembly issues may arise during service/maintenance operations following the application.

In applications in which the cistern tank is positioned in front of a panel (drywall, concrete, etc.,), the body of the cistern tank may outwardly expand through local stretches that may occur over time.

Several types of internal support elements are positioned inside the cistern tanks in order to avoid such problems. These supports make substantial contributions to minimizing the inward and outward stretching of the cistern tank.

The fact that the body of the cistern tank is divided into two parts from the lower or about the middle section of the access opening, may cause the cistern tank to exhibit a stretching behavior depending on constructional applications. This stretching behavior may give rise to even more serious problems, consequences of which may cause the cistern tank parts to become partially separated.

The most important reason underlying the fact that joining lines for cisterns tanks available in the state of the art are usually created at a level either lower or about the middle section of the access opening is to decrease height of the lower part of the cistern tank in particular and to facilitate the manufacturing process carried out by means of plastic injection molding method.

Problems the Invention Aims to Solve

The object of the present invention is to create a tank for a concealed cistern system that is divided into two parts from the level of the vertex (preferably the upper edge) of the access opening or higher and that is formed by joining said two parts together.

A major part of the tank body will be comprised of a single piece by means of the embodiment according to the present invention, thereby reducing or completely eliminating problems including the stretching that is stemming from the effects caused by operating the tank by concealing it, and problems that involve the parts forming the tank becoming partially separated from one another due to the occurring of said stretches.

Positioning the region, in which the parts of the cistern tank are joined together, at a relatively higher level will prevent several assembly/disassembly-related problems, which originate from stretching of components, from occurring during servicing/maintenance.

The embodiment according to the present invention also aims to achieve higher rigidity by supporting a rigid concealed cistern system tank consisting of two parts by means of the mounting relations of the access canal.

In fact, moving the joint between both parts of the cistern tank to the level of the upper edge of the access opening will make the joint even more durable and resistant since this will support joining both parts of the cistern tank by means of the mounting relations of the access canal.

Description of the Figures

Figure 1 illustrates the perspective general view of the concealed cistern system.

Figure 2 illustrates the perspective view of tank components and the access canal.

Figure 3 illustrates the perspective view of tank components and the access canal.

Figure 4 illustrates the partial perspective view of the tank body.

Figure 5 illustrates the perspective view of the tank lid.

Figure 6 illustrates the perspective view of the tank lid.

Figure 7 illustrates the perspective view of the tank lid.

Figure 8 illustrates the perspective view of the access canal.

Figure 9 illustrates the perspective and detailed view of the access canal.

Figure 10 illustrates the partial sectional view and detailed view of the joining of the tank components and the access canal.

Description of the References in the Drawings

A - Tank assembly A.l - Tank joining line

1 - Tank body

1.1. Snap-fit lugs

1.2. Access canal joining area

1.3. Access canal mounting clearance

1.4. Tank access opening

2 - Tank lid

2.1. Snap-fit extensions

2.2. Circumferential alignment protrusion

2.3. Access canal alignment step

2.4. Access canal fixing extension

2.4.1. Horizontal-axis locking extension

2.4.2. Snap-fit slot

2.5. Anti-stretch extension

3 - Access canal

3.1. Circumferential flange

3.2. Joining area

3.3. Alignment gap

3.4. Horizontal-axis locking clearance

3.5. Canal snap-fit extension

Description of the Invention

The present invention comprises the manner of joining a tank body (1) and a tank lid (2), which constitute a cistern tank assembly (A) in which the tank is structured in two parts, complemented with an access canal (3). The main object is to form a rigid structure particularly on the tank joining line (A.l).

The tank joining line (A.l) is created at the uppermost possible and the most suitable section of the tank assembly (A).

In the description provided herein, the components that constitute the tank assembly (A) are defined as the tank body (1) and the tank lid (2). Moving the tank joining line (A.l) to the uppermost possible and the most suitable section of the tank assembly (A) is the reason why the part that is located at the lower portion is defined as the body i.e., the tank body (1), while maintaining the horizontal length of the upper part at minimum is the reason why this part is defined as the tank lid (2).

To this end, at least one portion of the tank joining line (A.l) is created so as to intersect with the vertex of the access canal (3) according to a preferred embodiment of the present invention.

More specifically, the tank joining line (A.l) may be overlapped with the upper edge of the access canal (3).

This structure not only enables creating the tank joining line (A.l) at the uppermost possible and most suitable section of the tank assembly (A), but also allows for achieving a higher degree of rigidity by supporting the unison of tank assembly (A) with the mounting relations of the access canal (3).

In the structure according to the present invention; the circumferential alignment protrusion (2.2) of the tank lid (2) engages the tank body (1) when the tank lid (2) is positioned onto the tank body (1), snap-fit extensions (2.1) of the tank lid (2) form a fitting relation with the snap- fit lugs (1.1) located on the tank body (1), and the anti-stretch extensions (2.5) of the tank lid (2) support the tank body (1).

Tank access opening (1.4) is formed on the tank body (1). An access canal mounting clearance (1.3), in which the access canal (3) will be positioned, is available around the tank access opening (1.4). The access canal mounting clearance (1.3) is limited to the access canal joining area (1.2). In the mounted state of the access canal (3), a circumferential flange (3.1) of the access canal (3) is seated into the access canal mounting clearance (1.3) with a certain dimensional tolerance.

An access canal alignment step (2.3), which enables aligning and connecting the access canal (3) in a mounted state, is located on the tank lid (2). An alignment gap (3.3) located on the access canal (3) is joined with the access canal alignment step (2.3) on the tank lid (2) in a certain dimensional tolerance relation.

In the assembled state thereof, access canal fixing extension (2.4) on the tank lid (2) assume two functions in the fitting relation between the access canal (3) and the tank lid (2). Horizontal-axis locking extension (2.4.1) engages the horizontal-axis locking clearances (3.4) formed in the joining area (3.2) of the access canal (3). Concurrently, the connection of the access canal (3) to the tank lid (2) is made by means of the snap-fit joint relation of the canal snap-fit extensions (3.5) located in the alignment gap (3.3) of the access canal (3) to the snap-fit slots (2.4.2) located at the lower section of the access canal fixing extensions (2.4) (Figure 10).

It is assumed that the tank body (1) described in this document comprises internal structural supports that provide rigidity to the tank body in the levels remaining below the tank access opening (1.4) and that prevent the tank body from stretching inwards/outwards. The structural details related therewith are omitted as these details are not involved in the scope of the present invention.

As the tank joining line (A.l) is created at the uppermost possible and the most suitable level, any potential and already minimized stretching behavior that may occur at the upper section of the tank body (1) may be expected to happen only at that level. However, the tank assembly (A), in the assembled state thereof;

Prevents inward or outward stretching behavior at the joint of the tank body (1) and the tank lid (2),

A tank assembly (A) structure that is substantially more rigid in terms of preventing any possible stretching behaviors at the tank joining line (A.l) is achieved once the assembly of the access canal (3) is complete.

In alternative embodiments of the structure according to the present invention, different joint mechanisms may be preferred for fixing the access canal (3) instead of a snap-fit joint. For instance, screw/bolt fasteners may be given as an example to these joint mechanisms.