DESCRIPTION OF THE INVENTION Field of the invention

The present invention relates to structures or constructions for underground installations or installation networks, precisely to underground installations or installation networks for sewage system, fluid transport, electric power systems, telecommunications, more precisely to the chamber as an important part of these structures, especially the top part of such chamber.

State of the art

Structures for underground installations or installation networks were originally constructed as monolithic, built on-ihe-spot, or of reinforced concrete. Later, due to high organizational costs of construction in many dispersed places, they were developed as semi-prefabricated from

industrially manufactured elements, whereas recently they are entirely made as prefabricated structures that are easily joined together, in order to avoid fieldwork by use of expensive welding, soldering, brazing and similar equipment and achieve a minimum number of work operations at the place of installation.

Moreover, nowadays those structures are increasingly characterized by use of polymer compound materials, which, in addition to having good

mechanical properties, are also easy to transport and install, and highly resistant to corrosion resulting from aggression of chemical and physical influences from soil, environment and transported fluids. Due to exceptional physical and chemical properties such materials can also be durable and insulating safe from undesired passing of galvanic and stray currents, and currents induced by electrical installations, from the environment or by atmospheric discharge. When necessary, those materials can slightly adjust their shape to local conditions because of their plasticity.

Thus, many known installation network structure systems made of polymer compounds are in use. Chambers are important parts of each installation network and through them accessibility for the purpose of maintenance of underground network is ensured, at depths of approximately 0.3 to over 6 meters underground. Such chambers are installed in specific points of the network, generally, for inspection and cleaning, accessibility or repair in case of leakage of certain network sections, joining of branches and connection fittings to the network, addition or replacement of cables, and many other functions. Such chambers generally have a minimum inside width so that at least one person with minimum appropriate tools and equipment can concurrently enter and work therein and a depth extending from the surface of the ground to the depth of installation sections connected to the chamber. In chambers not intended for entry of persons, the entry width must in general be so large to enable free entry, exit and operation of equipment for various controls, cleaning, repair and any other operations that might be necessary, and which can be performed without person's entry into the chamber.

The solutions from the state of the art for the development of chamber shapes have not satisfied the combination of necessary load bearing capacity and preferable flexibility of the top part of the chamber to vertical loads.

Disclosure of the invention

The present invention provides an improved technical solution of the top part of the chamber for installations and installation networks, especially the top part of the chamber in underground installation networks for sewage system, fluid transport, electric power supply or telecommunications. The top part of the present invention comprises an upper part, selected from mainly cylindrical shape, mainly conical shape or a combination of said shapes, and a lower part. The lower part of the top part may be partly of conical, tapering or spherical shape. It is preferred that the lower part of the top part is at least partly radially corrugated, and that in this manner its load bearing capacity is increased. We particularly refer to loads from the ground and other loads that can appear in other applications of this top part, which can be multiplied in the proximity of the surface of the ground, generally due to extreme moving loads exerted by means of transport. The upper part of the top part which is an extension of the lower part of the top part is at least partly horizontally or axially corrugated in the manner that such horizontal corrugation acts as a spring, and in this manner its capacity to support horizontal loads is increased, while the effect of flexibility of form

(compensator) is ensured in case of transport of extreme vertical loads and temperature changes. The top parts of the chamber of the present invention can, amongst others, be produced with the rotational technique, which is more convenient and simple with respect to other techniques for production of polymer compound items, in terms of investment in tools and production plants, i.e., production process.

Brief description of the drawings

The illustrated drawings represent only a few examples of possible embodiments of the present invention, and do not in any manner limit the scope of patent protection of the present invention.

Figure 1 shows an axonometric top view of the top part (1) of the chamber of the present invention.

Figure 2 shows an axonometric bottom view of the top part (1 ) of the chamber of the invention with the embodiment comprising additional attachment for ladder.

Figure 3 shows an axonometric view of cut out top part (1 ) of the chamber of the invention with the embodiment comprising additional cover (5).

Figure 4 shows an axonometric view of cut out top part (1 ) of the chamber of the invention with the embodiment comprising additional height adapter (6). Figure 5 shows from a distanced axonometric view the top part (1) of the chamber of the invention within one of the possible embodiments comprising the whole chamber with the illustration of attachment for ladder.

Detailed description of the embodiments of the invention

Top part (1 ) of the chamber for installations, also called cone, comprises an upper part (2) selected from mainly cylindrical shape, mainly conical shape or a combination of said shapes, and a lower part of the top part (3). The upper part of the top part is at least partly horizontally corrugated in the manner that said horizontal corrugation acts as a spring. The lower part (3) of the top part can be partly of conical, tapering or spherical shape. It is preferred that the lower part (3) of the top part is at least partly radially corrugated, and that in this way its load bearing capacity is increased.

The upper part (2) is joined to the lower part (3). It is preferred that the upper part (2) of the top part and the lower part (3) of the top part are mutually eccentric in the manner that the lower part (3) of the top part is generally formed as a scalene cone.

The upper part (2) is at least partly corrugated in horizontal direction to increase the radial capacity to support loads from the ground, which in the proximity of the surface of the ground can multiply, generally due to extreme moving loads exerted by means of transport, ensuring at the same time relative vertical flexibility whereby large and concentrated moving load is distributed to the surrounding ground reducing its transfer to the chamber as a whole.

It is preferred that the lower part (3) is corrugated in radial direction in order to increase with this shape its support of loads from the ground and external moving loads transferred through the ground. The radial corrugation direction of the lower part plane (3) of the top part facilitates the sliding of mounded material when compressing the soil along the lower part (3) and excludes remaining of holes in the compressed material.

It is preferred that the upper part (2) is constructed so to enable entry in the chamber from the upper part of a person with tools and equipment and it can have a cover (5) or height adapter (6) on the top.

The top part (1 ) of the present invention can be produced by several different methods known to the person skilled in the art. Thus, the top part (1 ) can be produced in parts that would later be joined together or it can be produced in one piece.

The top part (1 ) of the chamber for installations or installation networks can be produced industrially in the manner that a metal mould (where the necessary amount of powder of a thermoplastic material was previously inserted) is rotated in the oven, so that the powder is distributed and melts on the inside mould wall. After cooling the mould is opened and the casting, which after the cutting process becomes a chamber element created by rotational technique, is extracted from the mould.

One of the preferred embodiments of the top part (1 ) of the chamber for installations comprises putting of one or more ladder attachments (4) for holding transportable ladder (8) for entry of person, which due to prevention of unauthorized access to the chamber, particularly of children, should not be fixed inside the chamber.

A further preferred embodiment of the top part (1 ) of the chamber for installations includes the possibility of applying a sealing element, a distancer on the inside of the upper part (2) in the part where it is corrugated, in case of installation of cover, cap, water tight cover, which can, but is not necessarily also gas tight, height adapter (6) or any other construction or element that needs the sealing element or distancer to fulfil its function.

Another preferred embodiment of the top part (1 ) of the chamber for installations includes the possibility of applying the sealing element or distancer on the outside of the upper part (2) in the part where it is

corrugated, in case of installation of concrete ring of various shapes and dimensions or any other element or construction to prevent direct contact with the top part, watertightness and prevent penetration of surrounding material.

A further preferred embodiment of the top part (1 ) of the chamber for installations includes the possibility of easy height adjustment, which can be reduced by cutting off the necessary part of the upper part (2) or extended using a special element or construction on the sealing joint or the distancer joint.

Different metal or duroplastic insets for this or other additional embodiments can remain captured in the casting.

The top part (1 ) of the chamber for installation can be made of any material that can be used in technical application field. It is preferred that said top part (1 ) is produced from polymer compounds, such as polyethylene,

polypropylene, polybutylene, PVC, and glass reinforced plastic. When using polymer compounds in the production of the present invention it is preferred to use the rotational casting technique. Furthermore, the present invention can be produced and used separately, when mounting installation systems on-the-spot. Moreover, the present invention comprises production and use as part of other elements, constructions, installations or installation systems.