Pipe coupling system

In pipe coupling systems, elaborate equipment and tools are required for their assembly and disassembly; the disassembly procedure is time consuming and little, if any, of the fittings can be reused. The present invention relates to improvements in pipe attachment system to their fittings, particularly adapted for use with smooth surface pipe and tubing where assembly and disassembly is easily made with simple tools or without tools. Except for the sealing ring, all parts of the system are reuseable without special preparation.

BACKGROUND OF THE INVENTION 
The invention is in the field of readily applicable and removeable 
clampable sleeve type couplings for effecting joints between pipes and 
their fittings. 
More specifically the coupling of the invention is intended for use with 
smoth surface pipes and tubing and their fittings as normally used in 
known and conventional methods of assembly such as threading soldering, 
glueing, brazing or welding. 
There is a need for a simple device to connect pipes to their fittings that 
is economical, not only to manufacture, but also in actual installation 
and use. 
Such a device, to achieve the greatest economy, must permit easy assembly, 
equally easy disassembly, and must permit the salvage of the maximum 
amount of components of the system; this device according to the invention 
permits the reusage, time after time, of all components provided their 
integrity is safeguarded. 
It is known that disastrous fires were caused, directly or indirectly, by 
the use of open flame or by the emanation of inflamable fumes and their 
subsequent ignition during the installation or alteration of plumbing 
systems; this device according to the invention eliminates these hazards 
since no flamable components, heat or flame is required for its 
installation. 
It is known that lack of thorough desoxydation and cleaning of the 
components of plumbing systems requiring soldering or glueing results in 
weak or leaking joints, which in turn require dismantling and 
reinstallation, sometimes at the cost of a number of new and extra 
fittings and material and great expense of time; this device according to 
the invention does not require such thorough desoxydation and cleaning, 
resulting in savings of time, because it relies on its composition seal 
for fluid tightness. Most known systems of pipe joints depend on their 
purposemade fittings, ordinarily compatible only within their own system, 
to function and their adaptability to different systems is very limited if 
non existent; this device according to the invention makes use of fittings 
normally used with other conventional joining methods without recurring to 
their hazard prone joining techniques and favors adaptation of this 
invention with other joining methods wherever tolerances between 
components permit. 
This flexibility permits the creation of hybrid systems where one side is 
joined conventionally and the other side with the coupling subject of this 
disclosure. 
Most known systems of pipe joints require the use of tools in the assembly 
and disassembly of the coupling or fitting; this device according to the 
invention offers the choice between hand or tool operable clamping means, 
which in hand operable clamping means offers an obvious time saving 
potential to the user. 
First development of the invention revealed a major weakness in its 
retaining means, which could accidentally be released while the system is 
pressurized and this condition was also found in Canadian Pat. No. 498,350 
to Ferguson Dec. 15, 1953; this undesirable feature is overcome in the 
device subject of the disclosure as only willfull release of the retainer 
sleeve, while the system is pressurised, may result in loss of fluid 
tightness. 
Some known systems of pipe joints depend on grooves in the pipe ends to 
mechanically secure the pipes to their fittings, said grooves being 
ordinarily square edged in profile to ensure more positive and non slip 
contact of retaining lugs; the device according to the invention makes 
similarly use of a groove in the end of the pipe and of the fitting to 
ensure a positive grip of the lugs both on the pipe and on the fitting end 
in a very different way as explained hereafter. 
This groove must be distinguished from the gasket seating groove whose 
function is solely related to the fluid tightness of the system, this 
first mentioned groove shall be called slip resisting groove as opposed to 
the gasket groove. 
The slip resisting groove need not be square in profile but may be of any 
profile suitable to provide slip resistance for the lugs of the retainer 
sleeve; depending on the pipe or fitting material this slip resisting 
groove can be square, V shaped or rounded according to the characteristics 
of the pipe or fitting material and the easiest method of forming such 
groove. The profile of the slip resisting groove is dictated by the stress 
characteristics of the material of the pipe and/or fitting; a rounded 
groove profile offers the benefit of minimizing the occurrence of 
localized stress points, ordinarily found to be the cause of failure, and 
provides an infinity of contact planes parallel to the end plane of the 
lugs; this is particularly important as it provides automatic adjustment 
for varying lug angles relatively to the pipe longitudinal axis, specially 
under varying pressure loads. 
It is known that soldered fittings can be unsoldered only when the fitting 
and the pipe adjacent thereto are completely drained; since the device 
according to the invention does not require any heat in order to be 
removed but only unlocking of the retainer sleeve, it is now clear that no 
time is wasted draining the system. 
This feature of easy removal leads to other potential economies since any 
such retainer sleeve used in conjunction with a end cap or any other type 
of fitting at low points of plumbing systems will act as low cost drains. 
Further research led to the present disclosure wherein a combination of 
the above described and some other desirable features are incorporated. 
The device and system according to the invention consist of the following: 
1. a clampable one piece split retainer sleeve, 
2. a hand or tool operable clamping means, 
3. a sealing gasket of known design and composition, 
4. a rounded groove in the pipe end to seat the sealing gasket, 
5. a slip resisting groove in the end of the pipe and of the fitting where 
such a groove is required by the nature of the pipe and/or fitting.

The numeral 1 indicates the retainer sleeve, which in FIG. 1 is wrapped 
around the end 2 of the fitting 3 and held in place with a clamping means 
4. The retainer sleeve 1 consists of a strip of spring type material with 
unequal shoulders 5, notched 6 to permit easy bending around the pipe 7 
and the fitting end 2; said retainer sleeve 1 exhibits one row of long 
sloping lugs 8 bent radially towards the fitting end 2 and engaging into 
the exterior surface of the pipe 7, while a second row of short sloping 
lugs 9 are bent in a similar but opposed direction to engage into the 
exterior surface of the fitting end 2. 
The retainer sleeve 1 is engaged by means of the short 9 and long 8 lugs 
respectively to the fitting end 2 and the pipe 7 in a semi-wrap around 
fashion, the opening 10 permitting the installation of the retainer sleeve 
1 without need of dismantling the pipe-fitting 7-3 assembly; the 
tightening or loosening of the clamping means 4 permits the securing or 
removing respectively of the retainer sleeve 1 to or from the pipe-fitting 
7-3 assembly. A gasket seating groove 11 is rolled, or otherwise 
fabricated at a predetermined distance from the end of the pipe 7, said 
groove to receive an annular gasket 12, or O ring, which gasket 12 
provides for the fluid tightness of the system; the composition of the 
gasket 12 shall be compatible with the type of fluid handled in the system 
and the type of material constituting the system. 
Referring to FIG. 3, the shoulders 5, the short 9 and the long 8 lugs are 
wrapped with a resilient material 13, which provides for even pressure 
distribution on the pipe 7 or fitting end 2; this optional protection is 
intended, among other things, to lessen pipe 7 or fitting 3 breakage due 
to thermal or mechanical stress built-up in brittle or fragile pipe 7 or 
fitting 3 material. 
Referring to FIG. 3, a second (slip resisting) groove 14 on the pipe 7 end 
is fabricated in a similar manner as the groove 11 destined to the gasket 
12; said second groove 14 acts as a mechanical stop providing slip 
resistance to the long 8 lugs. A similar arrangement in the form of a 
groove 15 is fabricated in the exterior surface of the fitting end 2 at a 
predetermined distance, said groove 15 acts as a mechanical stop for the 
short 9 lugs providing slip resistance against forces induced by pressure 
within the system. FIG. 5 shows in dotted lines the profile of two 
retainer sleeves 1, each displaying a preferred clamping means 4, which 
retainer sleeve 1 can be installed or removed without the use of tools; 
this illustrates some of a multitude of clamping means 4 suitable for the 
system according to design requirements. 
Many adaptations of the system are possible where the short 9 lugs and the 
adjacent shoulder 5 are replaced with a retaining means in the form of 
screw type serrations, lugs to fit in grooves or adaptable to screws 
screwable in the fitting 3 body. Joints made according to the disclosure 
are quite simple to make: 
Firstly the pipe 7 is prepared with a suitable tool by rolling or otherwise 
fabricating a groove 11 or a plurality of grooves 11-14 at a predetermined 
distance from the end of the pipe 7 in order for the first groove 11 to be 
completely lodged inside of the fitting end 2 when the pipe 7 is forced 
into said fitting end 2; 
Secondly an annular gasket 12, or O ring, is slipped over the pipe end 7 
and seated in the first groove 11 to provide for the fluid tightness of 
the system once inserted into the fitting end 2; 
Thirdly the fitting end 2 is inspected for smoothness and cleanliness and 
the prepared pipe 7, loaded with its sealing gasket 12, is inserted into 
the fitting end 2 until it butts against the inside shoulder or stop of 
the fitting 3; 
Fourthly the retainer sleeve 1 is opened and slipped over and around the 
pipe 7, positionned over the fitting end 2 and part of the pipe 7, at this 
point the clamping means 4 is thightened and the system is ready for 
testing and subsequent use. 
This step requires the checking that the lugs are falling into their 
respective slip resisting grooves when these are used; under normal 
conditions slip resisting grooves are not required or used and no other 
checking than that the pipe is fully inserted is required before applying 
clamp pressure. 
Reversing the procedure permits equally easy disassembly; reassembly, 
omitting step one, is immediately possible without further preparation of 
the components provided they are not damaged.