Title of Invention

PLASTIC PIPE COUPLER

Abstract

A plastic pipe coupler comprising plastic pipes (1) with a shouldered end (2) clamped with a pair of semi-circular U—section housing (3), an annular elastomer sealing ring (4) fits and engage al1 around on a surface formed by the said adjacent shouldered ends (2) and is toally enclosed by the said U-section housing (3) and held closed with bolts (5), wherein said annular elastomer sealing ring (4) has two sealing lips (6) and as under tension when fitted and seals the joint under pressure, said sealing effect futher increases by applying vacuum in the pipe line.

Full Text

This invention relates to a plastic pipe coupler for joining plastic pipes by mechanical means. Presently there are two types of plastic pipes available in the market being popularly used. They are 1) polyethylene (PE) and these polyvinyl chloride have different characteristics and joining methods. Polyethylene pipes are joined by fusion welding that is welding the ends together using heat. Though this method is economical but there are disadvantages associated with this. One of the main disadvantages with this method is that it requires considerable skill to make a reliable joint and this becomes increasingly difficult as the diameter of the pipe and the operating pressure in the pipe become larger and higher. Another disadvantages associated with the present method of joining polyethylene pipes is that it is inconvenient to arrange the required electricity supply at the site i.e. it requires a generating set to be taken whenever the pipes are being laid. PVC pipes are joined by solvent welding. In one end of the pipe a socket is formed in which the end of the next pipe is pushed. The inner surface of the socket and the outer surface of the pipe ends are moulded together using a solvent. - 2- There are disadvantages with the method of joining PVC pipes by solvent welding. One of the main disadvanage is that the reliability of this joining method depends on the skill and care of the worker. Another disadvantage of the method of PVC pipe joining by solvent welding is that it is not very reliable and cannot be done successfully in the rain or at times of high humidity. Therefore, the main object of the present invention is to propose a simple, effective and a versatile plastic pipe coupler. Another object of the present invention is to propose a plastic pipe coupler which requires no special skill or supervision. Yet another object of the present invention is to propose a plastic pipe coupler which requires no heating source at the site or any chemical solutions. Still another object of the present invention is to propose a plastic pipe coupler which can take high pressure and end loading. Thus the plastic pipe lines do not need anchoring or even under ground installation. - 3 - Further object of the present invention is to propose a plastic pipe coupler in which the load created by pressure in the pipe or weight of the pipe is distributed all around the circumference thus lowering the load per unit area to a level at which the plastic pipe will not distort. According to the present invention there is provided a plastic pipe coupler comprising plastic pipes with a shouldered and clamped with a pair of semi—circular U—Section housing, an annular-elastomer sealing ring fits and engage all around on a surface formed by the said adjacent shouldered ends and is totally enclosed by the said U—Section housing and held closed with bolts wherein the said annular elastomer sealing ring has two sealing lips and is under tension when fitted and seals the joint under pressure, said sealing effect further increases by applying vacuum in the pipe line. The nature of the invention, its objective and further advantages residing in the same will be apparent from the following description made with reference to non—limiting exemplary embodiments of the invention represented in the accompanying drawing. -4- Fig. 1 - shows the sectional view of the plastic pipe coupler assembly; Fig. 2 - shows the side view of the plastic pipe couplers; Fig. 3 - shows the elastomer sealing ring separately; Fig. 4 - shows the elastomer sealing ring fitted and under tension; Fig. 5 - shows the elastomer sealing ring under pressure; and Fig. 6 - shows the elastomer sealing ring under vaccum. In accordance of the present invention, two pipes (1) are joined by mechanical means. Plastic pipes (1) are each having a shouldered end (2) which is running around the circumference. They are made of plastic suitable for joining to the plastic pipe {1) by either fusion or solvent welding. The two adjacent shouldered ends (2) form a surface on which an elastomer sealing ring (4) fits. The sealing ring (4) ( Fig.3) has two sealing lips (6) that are under tension when fitted (Fig. 4). This seals the joint. Pressure or vacuum in the pipeline further increases the sealing effect by acting on surfaces (7) for pressure (Fig. 5) and (8) for vaccum ( Fig. 6) . - 5- The two shoulders (2) are engaged in a "U" section housing (3) of two or more pieces. The two or more pieces totally enclose the sealing ring (4) and engage all around the shoulders (2) and held closed by bolts (5) or suitable means. Shouldered ends (2) may also be formed on thermoplastic pipes by melting the pipe end and forming the shoulder in a heated die mounted on the pipe end. It is a characteristic of plastic to distort under load. With the present invention the load ereaed by pressure in the pipe or weight of the pipes is distributed all around the shoulders thus lowering the load per unit area to levels at which the plastic will not distort. The housing (3) can be made of metal or plastic, preferably of two or more uniform sections. In a preferred embodiment, the two sealing lips of the annular elastomer sealing ring is made from rubber and the plastic pipe is made from HDPE. The invention described hereinabove is in relation to a non-limiting embodiment and as defined by the accompanying claims. -6- WE CLAIM: 1. A plastic pipe coupler comprising plastic pipes (1) with a shouldered end (2) clamped with a pair of semi-circular U-section housing (3), an annular elastomer sealing ring (4) fits and engage all around on a surface formed by the said adjacent shouldered ends (2)" and is totally enclosed by the said U-section housing (3) and held closed with bolts (5), wherein said annular elastomer sealing ring (4) has two sealing 1ips (6) and is under tension when fitted and seals the joint under pressure, said sealing effect further increases by applying vacuum in the pipe line . 2. A plastic pipe coupler as claimed in claim 1 wherein the U-section housing (3) is made of two or more uniform section from metal or plastic. 3. A plastic pipe coupler as claimed in claim 1 wherein the shouldered ends (2) are made of plastic suitable for joining to the plastic pipe (1) by fusion or solvent welding. 4- A plastic pipe coupler as claimed in claim 1 wherein the shouldered ends (2) are also formed on thermoplastic pipes (1) by melting the pipe end and forming the shoulder (2) in a heated die mounted on the pipe (1) end. -7- 5. A plastic pipe coupler as claimed in claim 1 wherein the annular elastomer sealing ring with two sealing lips ( 6) is made from rubber. 6. A plastic pipe coupler as claimed in claim 1 wherein the pipe (1) is made of HDPE. 7. A plastic pipe coupler as herein described and illustrated. A plastic pipe coupler comprising plastic pipes (1) with a shouldered end (2) clamped with a pair of semi-circular U—section housing (3), an annular elastomer sealing ring (4) fits and engage al1 around on a surface formed by the said adjacent shouldered ends (2) and is toally enclosed by the said U-section housing (3) and held closed with bolts (5), wherein said annular elastomer sealing ring (4) has two sealing lips (6) and as under tension when fitted and seals the joint under pressure, said sealing effect futher increases by applying vacuum in the pipe line.

Documents:

02441-cal-1997-abstract.pdf

02441-cal-1997-claims.pdf

02441-cal-1997-correspondence.pdf

02441-cal-1997-description(complete).pdf

02441-cal-1997-drawings.pdf

02441-cal-1997-form-1.pdf

02441-cal-1997-form-2.pdf

02441-cal-1997-pa.pdf