Flexible pipe fitting

A pipe fitting is formed of a flexible body having a threaded coupling section at one end thereof. The coupling section has a portion integrally formed with the flexible body. A rigid shape-retaining portion is juxtaposed with the coupling section for enabling the coupling section dimensions to remain relatively constant when a member is secured to a threaded portion of the coupling section.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The field of art to which the invention pertains includes the field of 
flexible pipe fittings for lawn sprinkler systems, particularly, with 
respect to a pipe fitting having a rigid shape-retaining portion formed in 
the coupling section of the pipe. 
2. Description of the Prior Art 
In U.S. Pat. No. 3,759,455, there is illustrated a flexible pipe fitting 
which is used to interconnect a sprinkler and a pipe line and is usable to 
prevent damage and injury in the event the sprinkler or sprinkler riser is 
accidentally struck. The fitting is formed of a flexible tube with end 
members secured to opposite ends of the tube which form coupling sections 
for interconnecting the fitting to sprinkler heads or additional pipes. 
One difficulty with the aforementioned device is that the interconnection 
between the tube and the end members is such that a reduced interior bore 
is formed and pop-up type sprinkler heads do not have sufficient clearance 
to move in the junction area. Additionally, it has been found that the 
interconnection of the end members of the flexible tube tends to fail 
after a period of useage. One technique for improving the aforementioned 
fitting has been to integrally mold the end members and the flexible tube 
from a single type of material. However, by making the end members which 
form a thread coupling section of the same flexible material as the 
flexible tube, typically, i.e. PVC (polyvinyl chloride), it has been found 
that the sprinkler head threaded portion tends to deform the threaded 
coupling section. Additionally, it has been found that even after 
threading the coupling section to a device, if sufficient force is exerted 
on this junction, the threaded end of the coupling section can deform and 
be physically removed from the device. 
In order to overcome the attendant disadvantages of prior art flexible 
fittings, the present invention provides an integrally formed body and 
coupling section and a rigid shape-retaining portion in the coupling 
section. The shape-retaining portion enables the coupling section to 
remain relatively constant when a member is secured to the threaded 
portion of the coupling section or when a force is exerted on the coupling 
section or the member secured thereto. Thus, separation of the coupling 
section and the adjacent structure to which it is secured, such as an 
additional pipe or a sprinkler head, is prevented. 
SUMMARY OF THE INVENTION 
A pipe fitting comprises a flexible body having a threaded coupling section 
at one end thereof. The coupling section has a portion integrally formed 
with the flexible body. A rigid shape-retaining portion is juxtaposed with 
the coupling section for enabling the coupling section dimensions to 
remain relatively constant when a member is secured to a threaded portion 
of the coupling section. 
The advantages of this invention, both as to its construction and mode of 
operation, will be readily appreciated as the same becomes better 
understood by reference to the following detailed description when 
considered in connection with the accompanying drawings in which like 
reference numerals designate like parts throughout the Figures.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Referring now to FIG. 1, there is shown a pipe fitting 12 constructed in 
accordance with the principles of the invention and illustrated to show 
the use thereof. The pipe fitting 12 includes a threaded coupling section 
14 having a pop-up sprinkler head 16 secured thereto. Additionally, 
another coupling section (not shown) is normally integrally formed with 
the other end of the pipe fitting 12. When a force, illustrated by an 
arrow in FIG. 1, is applied to the pipe fitting 12 or the sprinkler head 
16 secured thereto, the pipe fitting flexes and prevents breakage of the 
pipe fitting at a coupling section or an intermediate portion thereof. 
Typically, the force illustrated by the arrow can be a lawn mower, a 
person's foot kicking the fitting, or other forces normally present on a 
lawn or other place where the sprinkler head 16 is utilized. 
Referring now to FIG. 2, the pipe fitting 12 is shown in partial cross 
section in order to explain the details of the invention. Typically, the 
pipe fitting 12 would be made of flexible molded material such as PVC and 
is formed of a flexible body 18 having the coupling section 14 integrally 
molded with one end thereof and a second coupling section 22 integrally 
molded at the other end thereof. 
A uniform bore 24 extends on the lengthwise interior of the flexible body 
and continues through the coupling sections. A rigid shape-retaining ring 
26 which will be described in greater detail hereinafter is positioned in 
the interior of the coupling section adjacent the end 28. The interior 
surface 32 of the ring 26 forms a continuation of the bore 24. The ring 26 
is normally made of a rigid type material and is initially placed on a 
mandrel (not shown) whose outer surface defines the dimensions of the bore 
24 and the fitting 12 is then molded on the mandrel and around the ring 
26. Normally, a shape-retaining ring (not shown) is also placed in the 
coupling section 22 and is indentical to the ring 26 illustrated in the 
coupling section 14 of FIG. 2. 
The coupling section 14 includes an outwardly extending conventional 
gripping flange 34 adjacent the area defining the interconnection between 
the flexible body 18 and the coupling section 14. The surface from the end 
28 of the coupling section 14 to the flange 34 is normally formed of 
threads 36 formed on the coupling section exterior surface enabling a 
device such as the sprinkler head 16 of FIG. 1 to be threadably secured 
thereto. 
The shape-retaining ring 26 is made of material which can reinforce the 
coupling section interior adjacent the threads 36. Typically, the material 
for the ring can be made of steel or other hard metal or wood or other 
plastic material. One sucessful material used to form the rigid 
shape-retaining ring is commonly referred to a ABS 
(Acrylonitrile-Butadine-Styrene) and is manufactured by Borg Warner under 
the trade name "Cycolac". 
The rigid shape-retaining ring 26 is shown in greater detail in FIG. 3 and 
is formed of a sleeve 38 whose interior surface 32 forms a continuation of 
the flexible body bore 24. At the sleeve end 42 a partial outwardly 
extending flange 44 is integrally formed with the annular sleeve. As 
illustrated in FIG. 3, the partial flange 44 is shown as a half are 
although lesser or greater arc lengths could be used as well. When the 
pipe fitting 12 is molded around the ring 26, portions of the coupling 
section 14 adjacent the flange free ends 52 and 54 abut these ends and 
prevent the sleeve from rotating about the pipe fitting bore 24 axis. 
Additionally, the bottom surface 56 of the flange and the top surface 58 
of the flange 44 also are juxtaposed with the molded adjacent portions of 
the coupling section thus preventing movement of the shape-retaining ring 
along the bore 24 axis. 
The other end 62 of the annular sleeve has a tapered surface 64 around 
which the coupling section front end 28 is molded and further prevents 
movement of the ring 26 along the bore 24 axis should the partial flange 
44 of the ring fail. In addition, as can be seen in FIG. 2, the rigid 
shape-retaining ring is positioned on the interior of the coupling section 
adjacent to the threaded end 36. The threaded end 36 is prevented from 
deforming when a sprinkler head 16 of FIG. 1 or other device is secured 
thereto. Moreover as previously mentioned, without the retaining ring 26, 
the flexible material adjacent the threaded end 36 can deform sufficiently 
to allow separation of a member secured thereto.