Swivel hose coupling with threaded nipple

A swivel coupling for terminating the end of a hose made of resilient material, the coupling having a tubular nipple with a barbed hose receiving portion at one end and a cylindrical end extending from the hose and having an O-ring seal extending therearound, and the coupling including a screw threaded fitting surrounding the cylindrical end of the nipple and sealed thereto by the O-ring and having an annular abutment adjacent to the hose, and the coupling further including an annular collar, separable into sectors in the form of shell portions which surround the hose and squeeze it against the barbed nipple, the collar having a grooved structure overlying the annular abutment of the screw fitting and retaining the fitting close to the hose while permitting it to swivel with respect to its axis, and the nipple having female wrench flats in its outer end and having external screw threads at its inner end beyond the barbed portion whereby the nipple can be screwed into the hose bore after the screw fitting and collar have been assembled to it.

BACKGROUND AND PRIOR ART 
There are many patents showing hose couplings for terminating a hose of the 
type used for air brake pressure lines, gasoline lines, water hoses, etc. 
However, in most cases those hose couplings which would be the most 
satisfactory are relatively expensive to manufacture. Therefore a less 
expensive type of hose coupling is often used which is not entirely 
satisfactory, since it may not adequately secure the hose to the nipple 
and/or screw fitting of the coupling. 
Efforts to overcome prior art disadvantages have often resulted in a 
complex and expensive coupling using a large number of parts which require 
complicated machining, and which can only be assembled using special 
tools. Moreover, most couplings provide no interengagement between the 
ferrule and the screw threaded fitting, whereby all of the strain tending 
to pull the hose out of the coupling must be borne by the barbs on the 
nipple. The applicant is not aware of any prior art showing the 
combination on a nipple including annular barbs to provide fluid tight 
sealing, a threaded portion to make it easier to screw the nipple into the 
bore of a hose, and wrench flats inside the central opening of the nipple 
to receive a tool by which the nipple can be rotated during insertion 
thereof into the bore of the hose. 
THE INVENTION 
The invention comprises an improved swivel coupling for connection with the 
end of a resilient hose, and including a tubular nipple having an outer 
surface which includes an annular barbed portion terminated by a threaded 
end which is insertable by screwing into the bore of the hose, and a 
cylindrical portion which extends beyond the hose and is received in the 
central passage of a screw threaded fitting having a cylindrical internal 
wall receiving the cylindrical portion of the nipple and sealed thereto by 
an O-ring. The central opening of the nipple has female wrench flats 
located near the outer end of the nipple which is remote from its threaded 
inner end, and operative to receive a tool by which the nipple can be 
rotated while screwing its threaded end into the hose bore. The 
surrounding screw fitting has a threaded portion extending away from the 
hose with external wrench flats adjacent to the threaded portion, the 
fitting also having an annular abutment extending around the fitting and 
located away from the threaded portion. The swivel coupling further 
includes an annular collar which is divided longitudinally of the coupling 
to provide multiple sectors or shell portions, which when assemblied 
together form a substantially annular internal surface having ribs 
therearound which are located such that when the hose is located within 
the shell portions and the latter are clamped tightly thereon, the annular 
ribs will clamp the hose securely to the barbed portion of the nipple. The 
collar also has an end portion which has an internal annular retaining 
member shaped to overlie and rotatably engage the tubular abutment of the 
screw fitting, thereby providing a sort of tongue and groove 
interengagement operative to prevent longitudinal separation of the screw 
fitting from the collar. 
OBJECTS AND ADVANTAGES OF THE INVENTION 
It is a principle object of this invention to provide a swivel coupling 
wherein the nipple is especially firmly anchored inside the bore of the 
hose, and wherein there is an additional annular interlocking structure 
between the collar which compresses the hose against the barbed end of the 
nipple and the screw threaded fitting of the assembly, so that the 
mechanical integrity of the engagement between the hose and the coupling 
is independent of the fluid-tight integrity therebetween, the coupling 
being greatly strengthened by such additional arrangements. 
It is another major object of the invention to provide a swivel coupling in 
which the fluid-tight integrity of the coupling is provided by an annular 
seal between the cylindrical end of the nipple and the internal 
cylindrical passage through the threaded fitting; and it is a further 
object to provide a swivel coupling in which the fluid-tight seal between 
the nipple and the threaded fitting is independent of the torque required 
to seat the threaded fitting during installation. 
Still another important object of the invention is to provide inside the 
opening of the tubular nipple female wrench flats facing away from the 
hose receiving portion of the nipple and adapted to receive a tool which 
can be inserted therein and rotated to screw the threaded end of the 
nipple into the hose bore during installation. There are two ways to 
assemble these parts to form a completed coupling on the end of a hose. 
First, during factory assembly of the hose and coupling, the screw fitting 
is slipped onto the nipple and the hose receiving end of the nipple is 
then pushed into the hose. Afterward, the shell segments of the annular 
collar are assembled about the hose and the screw fitting, and then the 
shell segments are compressed on the hose and the band is forced onto the 
segments using a special tool. However, the coupling can be fitted to the 
hose in a second way which can be done in the field without any special 
assembling tools. This is done by using a different sequence of operations 
wherein the screw fitting is placed against the end of the hose, and the 
shell segments are assembled around the hose and interlocked with the 
abutment on the screw fitting. The band is then slipped onto the segments 
and is tight enough to keep them assembled. Thereafter the hose receiving 
end of the nipple is lubricated and inserted through the screw fitting 
into the end of the hose. An Allen wrench is then inserted into the female 
flats in the outer end of the nipple and used to screw the nipple right 
into the hose until its outer end is flush with the outer end of the screw 
fitting, whereupon the assembly is completed. 
It is a further object of the invention to provide a collar which is 
longitudinally divided into multiple sectors comprising identical shell 
portions which are chamfered to receive an encircling band for compressing 
the collar onto the hose. This type of construction provides a coupling 
which can be made less expensively and which is easier to install at the 
end of a hose. 
Other objects and advantages of the invention will become apparent during 
the following discussions of the drawing.

PREFERRED EMBODIMENT 
Referring now to the drawings, the Figures show a length of hose H to which 
a swivel coupling is connected. The coupling comprises a tubular nipple 10 
having a central opening 11 extending therethrough, and having on its 
outer surface a cylindrical portion 12 near one end and a hose receiving 
portion including a screw threaded portion 17 at is other end with an 
annular barbed portion 13 located therebetween. In the vicinity of the 
cylindrical end 12, there is an external annular groove 14 in which an 
annular seal 15 such as an O-ring is inserted, and there are female wrench 
flats 18 in the central opening. 
The coupling further includes a screw threaded fitting 20 having a passage 
21 through its center which comprises a cylindrical wall portion snuggly 
receiving the cylindrical portion 12 of the nipple 10, and sealing against 
the O-ring 15. The fitting 20 further includes a threaded portion 22 which 
faces away from the hose H and has external wrench flats 23 of hexagonal 
shape located adjacent to the threaded portion 22. Near the end of the 
fitting 20 which is located adjacent to the hose, the fitting includes an 
annular abutment 24 which in the illustrated embodiment comprises an 
annular ring around the body 25 of the fitting, although the shape of the 
abutment 24 need not necessarily be cylindrical. The internal cylindrical 
wall portion 21 of the fitting 20 is stepped as at 26 to a smaller 
internal diameter 27, and this shoulder 26 lies against the annular 
shoulder 16 around the nipple as can be seen in FIG. 4, thereby providing 
on the two parts interfering means which prevent the nipple 10 from being 
pulled all the way through the threaded fitting 20. 
The hose H is compressed tightly between the barbed portion 13 of the 
nipple 10 and an annular collar 30 which is divided longitudinally of the 
axis A of the fitting, thereby dividing the collar into multiple sectors 
comprising shell portions such as 31 and 32 as can be seen in FIG. 4. 
Although only two such shell portions are shown in the drawings, it is to 
be understood that the collar 30 can be divided into three or more shell 
portions as may be desired. The collar 30 and its shell portions 31 and 32 
have annularly ribbed internal surfaces 33 which are designed to provide 
an undulating engagement with the outer surface of the hose H and squeeze 
it onto the the barbed portion 13 of the nipple 10. Moreover, the collar 
30, when assembled, has an annular internal retaining structure which is 
labeled 34, 35, and 36 in FIG. 1 and is designed to surround the abutment 
ring 24 of the fitting 20 and thereby hold it against longitudinal 
displacement in the direction of the axis A with respect to the collar 30 
and the hose H. The structures 34, 35 and 36, taken with the abutment ring 
24, provide a sort of annular tongue and groove arrangement which permits 
rotation of the fitting 20 with respect to the collar 10 during coupling 
to, or removal from, some other mating fitting (not shown). 
The shell portions 31 and 32 of the annular collar 30 are held tightly 
pressed against the hose H by a band 38 which surrounds the shell portions 
of the collar 30 and fits into an annular groove 37. It will be noted that 
the band 38 is large enough to overlie the hose H and freely slide 
thereon, and that the shell portions 31 and 32 are beveled at the ends 31a 
and 32a to match a bevel 39 located internally at one end of the band 38. 
When the shell portions 31 and 32 are being installed on the hose during 
mass production, they are mechanically squeezed onto the outer periphery 
of the hose H by a special tool (not shown) tightly enough so that the 
band 38 can be forced over the shell portions and into the groove 37 by 
applying axial thrust to the band 38, whereby to drive its tapered portion 
39 upwardly onto the bevels 31a and 32a of the shell portions of the 
collar 30. After the band 38 has been snapped into the groove 37 around 
the collar 30, the collar is then allowed to expand slightly outwardly 
against the band, the diameter of the band being such as to maintain 
proper compression between the collar, the hose, and the hose receiving 
outer surface 13 of the nipple 10. Thus, once the swivel coupling has been 
fully installed upon the hose H, the only part which undergoes any 
substantial distortion from its original shape is the hose H because the 
nipple, and the band 38 and the collar 30 are substantially rigid and 
nondeformable. 
During the alternative method of assembly, which can be done in the field 
without special tools, the shell portions can be assembled first around 
the hose and screw fitting and held in place by the band 38, and then the 
nipple can be screwed into the hose through the screw fitting and 
installed shell portion, thereby internally expanding the hose outwardly 
to fill the shell portions as the nipple enters deeper into the bore of 
the hose. 
Although it is an advantage of the invention that the nipple 10 and the 
collar 30 can be made of plastic, as shown in the preferred embodiment, 
there is no reason why these parts cannot be made of metal or any other 
suitable material which is dimensionally stable and non-corrodable. The 
threaded fitting 20 is preferably made of brass or some other 
non-corrodable metal, whereas the band 39 can be made of steel suitably 
protected on its outer surface by plating. 
The present invention is not to be limited to the exact embodiments shown 
in the drawings, for obviously changes can be made within the scope of the 
following claims.