GB1595497A - Access points for drainage and sewerage pipes - Google Patents

Description

(54) AN IMPROVEMENT IN OR RELATING TO ACCESS POINTS FOR DRAINAGE AND SEWERAGE PIPES (71) We, PARAGON PLASTICS LIMITED, a British Company, of Broomhouse Lane, Edlington, Doncaster 12, 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: The invention relates to access points for drainage and sewerage pipes and has for its object to provide an improvement therein.

According to one aspect of the invention there is provided an inspection chamber providing an access point for a drainage or sewerage pipe, the chamber including a body part with spigot portions for connection in a pipe run, that is to say for connection to respective lengths of water drainage pipe or sewerage pipe, and with an integral moulded socket portion giving access to a flow passage between the spigot portions, said socket portion being of elongate shape with half round ends and having an internal shoulder formed a short distance below an upper end thereof, the chamber also including an access pipe part formed from a length of synthetic plastics pipe having a bore diameter greater than the width of the flow passage, an end portion of said pipe having been deformed by being partially flattened, inserted into the socket portion of the body part and secured therein by welding or by an adhesive. The two parts will preferably have been united by solvent welding.

According to another aspect of the invention, there is provided a method of making an inspection chamber as described above, the method including the moulding of a body part with spigot portions for connection in a pipe run and with an integral socket portion giving access to a flow passage between said spigot portions, said socket portion being of elogate shape with half round ends, and having an internal shoulder formed a short distance below an upper end thereof, the method also including the forming of an access pipe part by deforming one end of a length of sythetic plastics pipe, that is to say simply by partially flattening that end of the pipe, inserting that end of the access pipe part in the socket portion and securing it therein by welding or by an adhesive.

In order that the invention may be fully understood and readily carried into effect, the same will now be described, by way of example only, with reference to the accompanying drawings, in which: Fig. 1 is a part-sectional side view of an inspection chamber embodying the invention, Fig. 2 is a plan view thereof, Fig. 3 is an end view, Fig. 4 is a sectional view on the line 44 in Fig, 1, and Figs. 5 to 8 are views which will be referred to when describing possible modifications.

Referring now to Figs. I to 4 of the drawings, the inspection chamber there illustrated includes a body part 10 moulded in a synthetic plastics material and provided with spigot portions 12 for connection in a pipe run, that is to say for connection to respective lengths of water drainage pipe or sewerage pipe such as shown in chain-dotted lines in Fig. 1. The body part 10 is provided also with an integral socket portion 14 which gives access to a flow passage 16 of circular section between the spigot portions. However, the socket portion is not of circular shape but is of elongate shape with half round ends as shown in Figs. 2 and 4. An internal shoulder 18 is formed a short distance below the upper end of the socket portion, and occupies a plane parallel to but spaced from the axis of the flow passage 16.

The inspection chamber includes also an access pipe part 20 which has been formed from a length of synthetic plastics pipe having a bore diameter greater than the diameter of the flow passage 16, but as indicated in the drawings an end portion 22 of said pipe has been deformed. simply by partially flattening that end of the pipe. so that it has been able to be inserted into the socket portion of the body part to abut against the shoulder 18. The distance around the inside surface of the socket portion 14 is of course substantially equal to the outer circumference of the synthetic plastics pipe from which the access pipe part has been formed. The two parts have been united by solvent welding.

It will be understood that the access pipe part 20 can be of any length to suit the particular site in which the inspection chamber is to be used, that is to say it will be of a length to suit the depth below ground level of the body part. The local enlargements 24 at the opposite ends of the socket portion 14 of the body part are provided to receive screws which may be used to secure a cover piece in position on the body part if it is desired to install the latter in a position where the access pipe part is not rcquired. For example, the right hand portion of Figs. 5 and 6 illustrate a thermoplastics cap in the form of a flat sheet secured to the body part by means of screws 28, a sealing compound having been used to ensure a leak proof seal.

The left hand portions of Figs. 5 and 6 illustrate the fitment of a closure cap to the upper end of the access pipe part. An aluminium shroud 30 has been permanently cemented in position at the upper end of said access pipe part and an aluminium cover piece 32 is accommodated within the shroud, as shown, and is secured in position by means of screws 34.

In Figs. 7 and 8 which arc views similar to the right hand portions of Figs. 5 and 6, there is illustrated a modification in which the thermoplastics cap 26 in the form of a flat sheet of material has been replaced by a plastics moulding in the form of an open topped hollow member generally indicated 36 which is able to be seated within the socket portion 14 of the body part in the manner of the access pipe part. The cap 26 is thus better able to stiffen the socket portion 14 against inwards deformation and is assisted in this by the fact that it has a central bracing web 38 extending across it midway of its length.

Various other modifications may be made without departing from the scope of the invention. For example. it will be understood that the upper end of the access pipe part need not necessarily be of circular section but could be of square or rectangular section if preferred (but of course this would make the forming of the lower end of the access pipe part more difficult even though the length of its perimeter would still be such as to suit the distance around the inside surface of the socket portion 14 of the body part).

WISAT WE CLAIM IS: 1. An inspection chamber providing an access point for a drainage or sewerage pipe, the chamber including a body part with spigot portions for connection in a pipe run, that is to say for connection to respective lengths of water drainage pipe or sewerage pipe. and with an integral moulded socket portion giving access to a flow passage between the spigot portions, said socket portion being of elongate shape with half round ends and having an internal shoulder formed a short distance below an upper end thereof, the chamber also including an access pipe part formed from a length of synthetic plastics pipe having a bore diameter greater than the width of the flow passage, an end portion of said pipe having been deformed by being partially flattened, inserted into the socket portion of the body part and secured therein by welding or by an adhesive.

2. An inspection chamber according to claim I, in which the two parts have been united by solvent welding.

3. A method of making an inspection chamber as claimed in claim 1, the method including the moulding of a body part with spigot portions for connection in a pipe run and with an integral socket portion giving access to a flow passage between said spigot portions, said socket portion being of elongate shape with half round ends and having an internal shoulder formed a short distance below an upper end thereof, the method also including the forming of an access pipe part by deforming one end of a length of synthetic plastics pipe, that is to say simply by partially flattening that end of the pipe, inserting that end of the access pipe part in the socket portion and securing it therein by welding or by an adhesive.

4. An inspection chamber providing an access point for a drainage or sewerage pipe, constructed and arranged substantially as hereinbefore described with reference to and as illustrated by Figs. 1 to 4 of the accompanying drawings.

5. A method of making an inspection chamber, substantially as hereinbefore described with reference to and as illustrated by Figs. 1 to 4 of the accompanying drawings.

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

Claims (5)

**WARNING** start of CLMS field may overlap end of DESC **. indicated in the drawings an end portion 22 of said pipe has been deformed. simply by partially flattening that end of the pipe. so that it has been able to be inserted into the socket portion of the body part to abut against the shoulder 18. The distance around the inside surface of the socket portion 14 is of course substantially equal to the outer circumference of the synthetic plastics pipe from which the access pipe part has been formed. The two parts have been united by solvent welding. It will be understood that the access pipe part 20 can be of any length to suit the particular site in which the inspection chamber is to be used, that is to say it will be of a length to suit the depth below ground level of the body part. The local enlargements 24 at the opposite ends of the socket portion 14 of the body part are provided to receive screws which may be used to secure a cover piece in position on the body part if it is desired to install the latter in a position where the access pipe part is not rcquired. For example, the right hand portion of Figs. 5 and 6 illustrate a thermoplastics cap in the form of a flat sheet secured to the body part by means of screws 28, a sealing compound having been used to ensure a leak proof seal. The left hand portions of Figs. 5 and 6 illustrate the fitment of a closure cap to the upper end of the access pipe part. An aluminium shroud 30 has been permanently cemented in position at the upper end of said access pipe part and an aluminium cover piece 32 is accommodated within the shroud, as shown, and is secured in position by means of screws 34. In Figs. 7 and 8 which arc views similar to the right hand portions of Figs. 5 and 6, there is illustrated a modification in which the thermoplastics cap 26 in the form of a flat sheet of material has been replaced by a plastics moulding in the form of an open topped hollow member generally indicated 36 which is able to be seated within the socket portion 14 of the body part in the manner of the access pipe part. The cap 26 is thus better able to stiffen the socket portion 14 against inwards deformation and is assisted in this by the fact that it has a central bracing web 38 extending across it midway of its length. Various other modifications may be made without departing from the scope of the invention. For example. it will be understood that the upper end of the access pipe part need not necessarily be of circular section but could be of square or rectangular section if preferred (but of course this would make the forming of the lower end of the access pipe part more difficult even though the length of its perimeter would still be such as to suit the distance around the inside surface of the socket portion 14 of the body part). WISAT WE CLAIM IS:

1. An inspection chamber providing an access point for a drainage or sewerage pipe, the chamber including a body part with spigot portions for connection in a pipe run, that is to say for connection to respective lengths of water drainage pipe or sewerage pipe. and with an integral moulded socket portion giving access to a flow passage between the spigot portions, said socket portion being of elongate shape with half round ends and having an internal shoulder formed a short distance below an upper end thereof, the chamber also including an access pipe part formed from a length of synthetic plastics pipe having a bore diameter greater than the width of the flow passage, an end portion of said pipe having been deformed by being partially flattened, inserted into the socket portion of the body part and secured therein by welding or by an adhesive.

2. An inspection chamber according to claim I, in which the two parts have been united by solvent welding.

3. A method of making an inspection chamber as claimed in claim 1, the method including the moulding of a body part with spigot portions for connection in a pipe run and with an integral socket portion giving access to a flow passage between said spigot portions, said socket portion being of elongate shape with half round ends and having an internal shoulder formed a short distance below an upper end thereof, the method also including the forming of an access pipe part by deforming one end of a length of synthetic plastics pipe, that is to say simply by partially flattening that end of the pipe, inserting that end of the access pipe part in the socket portion and securing it therein by welding or by an adhesive.

4. An inspection chamber providing an access point for a drainage or sewerage pipe, constructed and arranged substantially as hereinbefore described with reference to and as illustrated by Figs. 1 to 4 of the accompanying drawings.

5. A method of making an inspection chamber, substantially as hereinbefore described with reference to and as illustrated by Figs. 1 to 4 of the accompanying drawings.