GB1604042A - Drainage access chamber - Google Patents

Description

(54) DRAINAGE ACCESS CHAMBER (71) We, IMI YORKSHIRE IMPERIAL PLASIICS L1MITED (formerly, Yorkshire Imperial Plastics Limited), a British Company, of PO Box 166, Leeds LS1 1RD, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- This invention relates to drainage access chambers, for example those disclosed in British Patent Specifications 1 157 431, 1197 233, 1 269 351, 1 297 562, 1 392 228, 1 430 305 and 1 485 757.

Drainage access chambers are installed in drainage systems for the purpose of permitting access whereby a connected drain can be cleansed, and any obstructions to the drain removed by a rodding operation, the rod being inserted via the drainage access chamber.

According to the present invention there is provided a moulded plastics drainage access chamber having a laterally-directed outlet at its base for connection to a drainage pipe, and an integrally moulded inlet con nection in the chamber wall above the later ally directed outlet, said inlet connection comprising a pipe boss surrounding a por tion of the chamber wall, said portion being cut away during installation of the chamber to provide a fluid flow passageway from the interior of the boss to the chamber.

The boss may comprise a pair of co-axial cylindrical extensions from the wall of the chamber, the annular space therebetween being adapted to provide a socket for a pipe to be connected to the boss.

A separable extension portion may be provided at the upper end of the chamber, and such extension portion may be cylindrical in shape. An inlet connection may be carried by the separable extension portion alone.

The chamber may have any desired shape.

For example, it may be bowl shaped (or approximately part spherical), conical, cylin drical or polygonal. The chamber may com prise combinations of different shapes such as those outlined above; for example, the chamber may have a conical wall portion and a cylindrical wall portion as illustrated in British Patent Specification 1 430 305.

Where the chamber comprises combinations of differently shaped parts, there may be one or more bosses on one or both parts.

The side wall(s) of the chamber will preferably, at least in their lower regions, converge towards the laterally-directed outlet at the base of the chamber and will preferably be provided with a plurality of pipe bosses, preferably extending outwardly from the chamber, each having a fluid passageway therethrough blocked by a portion of the chamber wall which can be cut away during installation of the chamber.

One or more incoming drainpipes may then be connected to the access chamber by means of one or more appropriately oriented bosses, the chamber wall portions associated with those bosses being removed but any unused boss or bosses remaining blocked by its, or their respective chamber wall portion(s).

The drainage access chamber may be provided with a removable cover mounted on the chamber in airtight sealing engagement therewith.

By way of example one embodiment of the invention will now be described with reference to the accompanying diagrammatic drawing. The drainage access chamber shown in the drawings is basically similar to that shown in our prior British Patent Specification 1 297 562, and comprises a conical bowl 10 which merges into an integral laterally directed conduit section 12 at its lower end. The interior of the bowl is in flow communication with the conduit section 12. The conduit section 12 can be connected into a main drainage conduit by suitable connection portions 14.

In-feed pipes can feed liquids via the interior of the bowl 10 to the main drainage conduit 12. The pipes can be connected to bosses 16. The bosses 16 are of similar construction and the right-hand boss in the drawing is shown sectioned. Each boss comprises an outer cylindrical wall 18 and an inner cylindrical wall 20, providing bet ween them an annular socket which is dimensioned to receive an end portion of a pipe.

The walls 18 and 20 are formed integral with the bowl 10 from a suitable moulded plastics material. As can be seen in the drawing, the central passage 22 in the boss 16 is closed at its inner end by wall section 24 of the bowl 10. However, when it is desired in use to connect a pipe to the bowl via a particular boss 16, the wall section 24 associated with that boss can be cut away from the body of the bowl, leaving a flow passage from the pipe to the interior of the body, and hence to the conduit section 12.

The pipe received in the annular socket of the boss 16 may be adhesively or otherwise secured therein, by means well known in the plastics art. It is not essential to provide the inner wall 20 of the boss 16, since the pipe could simply be secured to the outer wall 18 of the boss 16. Suitable sealing means, for example an O-ring, may be included in the connection, for example between the wall 18 and the pipe.

Equally, it would be possible to omit the outer wall 18, and to secure the pipe around the inner wall 20, again by adhesive if desired. A suitable seal could again be provided.

A bowl having a portion of one shape, for example conical as shown at 10 in the figure, could have a portion of another shape, for example the separable cylindrical extension 26 shown in the drawing at its upper end. If this extension is used, it would be moulded to fit the upper edge of the conical bowl 10. The cylindrical extension is also shown with bosses 16; however, if the conical bowl 10 has bosses 16 such bosses may be omitted from the extension; on the other hand, if tbe extension 26 has bosses 16, they may be omitted from the bowl 10.

In any arrangement in accordance with the invention, the upper end of the chamber is preferably provided with a removable cover which can be sealed to the chamber in an airtight fashion.

WHAT WE CLAIM IS: 1. A moulded plastics drainage access chamber having a laterally-directed outlet at its base for connection to a drainage pipe, and an integrally moulded inlet connection in the chamber wall above the laterallydirected outlet, said inlet connection comprising a pipe boss surrounding a portion of the chamber wall, said portion being cut away during installation of the chamber to provide a fluid flow passageway from the interior of the boss to the chamber.

2. A drainage access chamber as claimed in claim 1 in which the boss comprises a pair of co-axial cylindrical extensions from the wall of the chamber, the annular space therebetween being adapted to provide a socket for a pipe to be connected to the boss.

3. A drainage access chamber as claimed in Claim 1 or Claim 2 in which the chamber includes at its upper end a separable extension portion.

4. A drainage access chamber as claimed in claim 3 in which the extension portion is cylindrical in shape.

5. A drainage access chamber as claimed in Claim 3 or Claim 4 in which only the separable extension portion carries an inlet connection.

6. A drainage access chamber as hereinbefore described with reference to and as shown in the accompanying drawing.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (6)

**WARNING** start of CLMS field may overlap end of DESC **. ween them an annular socket which is dimensioned to receive an end portion of a pipe. The walls 18 and 20 are formed integral with the bowl 10 from a suitable moulded plastics material. As can be seen in the drawing, the central passage 22 in the boss 16 is closed at its inner end by wall section 24 of the bowl 10. However, when it is desired in use to connect a pipe to the bowl via a particular boss 16, the wall section 24 associated with that boss can be cut away from the body of the bowl, leaving a flow passage from the pipe to the interior of the body, and hence to the conduit section 12. The pipe received in the annular socket of the boss 16 may be adhesively or otherwise secured therein, by means well known in the plastics art. It is not essential to provide the inner wall 20 of the boss 16, since the pipe could simply be secured to the outer wall 18 of the boss 16. Suitable sealing means, for example an O-ring, may be included in the connection, for example between the wall 18 and the pipe. Equally, it would be possible to omit the outer wall 18, and to secure the pipe around the inner wall 20, again by adhesive if desired. A suitable seal could again be provided. A bowl having a portion of one shape, for example conical as shown at 10 in the figure, could have a portion of another shape, for example the separable cylindrical extension 26 shown in the drawing at its upper end. If this extension is used, it would be moulded to fit the upper edge of the conical bowl 10. The cylindrical extension is also shown with bosses 16; however, if the conical bowl 10 has bosses 16 such bosses may be omitted from the extension; on the other hand, if tbe extension 26 has bosses 16, they may be omitted from the bowl 10. In any arrangement in accordance with the invention, the upper end of the chamber is preferably provided with a removable cover which can be sealed to the chamber in an airtight fashion. WHAT WE CLAIM IS:

1. A moulded plastics drainage access chamber having a laterally-directed outlet at its base for connection to a drainage pipe, and an integrally moulded inlet connection in the chamber wall above the laterallydirected outlet, said inlet connection comprising a pipe boss surrounding a portion of the chamber wall, said portion being cut away during installation of the chamber to provide a fluid flow passageway from the interior of the boss to the chamber.

2. A drainage access chamber as claimed in claim 1 in which the boss comprises a pair of co-axial cylindrical extensions from the wall of the chamber, the annular space therebetween being adapted to provide a socket for a pipe to be connected to the boss.

3. A drainage access chamber as claimed in Claim 1 or Claim 2 in which the chamber includes at its upper end a separable extension portion.

4. A drainage access chamber as claimed in claim 3 in which the extension portion is cylindrical in shape.

5. A drainage access chamber as claimed in Claim 3 or Claim 4 in which only the separable extension portion carries an inlet connection.

6. A drainage access chamber as hereinbefore described with reference to and as shown in the accompanying drawing.