U.S. patent number 3,877,731 [Application Number 05/397,428] was granted by the patent office on 1975-04-15 for coupling.
Invention is credited to Edmund J. Kraus, Robert A. Kraus.
United States Patent |
3,877,731 |
Kraus , et al. |
April 15, 1975 |
Coupling
Abstract
A coupling including a duality of identical members, each of
which includes inside and outside threads which are meshed when the
coupling is mated, the members including tabs extending forwardly
into recesses and having detent means for holding the members in
the mated position.
Inventors: |
Kraus; Robert A. (Tustin,
CA), Kraus; Edmund J. (Santa Ana, CA) |
Family
ID: |
23571160 |
Appl.
No.: |
05/397,428 |
Filed: |
September 14, 1973 |
Current U.S.
Class: |
285/82;
285/70 |
Current CPC
Class: |
F16L
37/252 (20130101) |
Current International
Class: |
F16L
37/00 (20060101); F16L 37/252 (20060101); F16l
035/00 () |
Field of
Search: |
;285/70,73,76,79,82,74,305,311,314 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Larkin; Geo. V.
Attorney, Agent or Firm: Gausewitz, Carr &
Rothenberg
Claims
What is claimed is:
1. A coupling device comprising
a duality of integral tubular members,
each of said members including an end portion having
a first outside thread extending partway therearound from an
entrance thereto to an inner end thereof,
a second inside thread extending partway therearound from an
entrance thereto at at a different location from said entrance to
said first outside thread to an inner end thereof at a different
location from said inner end of said first outside thread such that
when said end portions of said members are brought into engagement
and relatively rotated said first thread of each of said members
meshes with said second thread of the other of said members so that
said members assume a mated position,
at least one of said first and second threads of each of said
members having a shoulder adjacent the entrance thereto,
said shoulders of said members being opposite from each other and
in adjacency when said members so assume said mated position,
and sealing means,
said sealing means being in interengagement when said members are
in said mated position.
2. A device as recited in claim 1 in which said end portions of
said members are identical.
3. A device as recited in claim 1 in which said members are of
plastic material.
4. A device as recited in claim 1 including in addition detent
means for holding said members in said mated position.
5. A device as recited in claim 1 in which said outside thread and
said inside thread of each of said members are of substantially the
same thickness.
6. A device as recited in claim 1 in which
said outside thread is in at least two parts,
and said inside thread is in at least two parts,
with said parts of said inside thread being intermediate said parts
of said outside thread.
7. A device as recited in claim 6 in which said parts of said
outside thread are diametrically opposed, and said parts of said
inside thread are diametrically opposed.
8. A device as recited in claim 6 in which the entrances to said
outside threads and said inside threads are in the same plane,
which plane is radial with respect to said member.
9. A device as recited in claim 1 in which
said outside thread is in two diametrically opposed parts,
each of said parts of outside thread extending through an arc of
substantially 90.degree.,
and said inside thread is in two diametrically opposed parts,
each of said parts of said inside thread extending through an arc
of substantially 90.degree.,
said parts of said inside thread being intermediate said parts of
said outside thread.
10. A device as recited in claim 1 in which
said outside thread has an axially outer flank surface extending to
the entrance to said inside thread,
said surface of said outside thread having a continuation thereof
extending beyond said outside thread in parallelism with said
inside thread to define a first helical groove,
said inside thread has an axially outer flank surface extending to
the entrance of said outside thread,
said surface of said inside thread having a continuation thereof
extending beyond said inside thread in spaced parallelism with said
outside thread to define a second helical groove,
and in which when said members assume said mated position said
outside thread of each of said members is received in said first
helical groove of the other of said members, and said inside thread
of each of said members is received in said second helical groove
of the other of said members.
11. A device as recited in claim 10 in which the axially outer
flank surfaces of said inside and said outside threads fall in the
same plane at diametrically opposed locations, which plane is
radial with respect to said member.
12. A device as recited in claim 10 in which, when said members are
in said mated position,
said axially outer flank surface of said inside thread of one of
said members is in juxtaposition with said continuation of said
axially outer flank surface of said inside thread of the other of
said members, and the entrances to said inside threads of said
members are in juxtaposition,
whereby said members present a substantially smooth surface at the
joint between said first and second members.
13. A device as recited in claim 1 in which
each of said members has at least one tab extending axially
outwardly of said end portion thereof. and has a recess extending
axially inwardly of said end portion for receiving said tab of the
other of said members.
14. A device as recited in claim 13 in which
each of said members includes a duality of said tabs,
said tabs extending axially outwardly from the entrances to said
outside threads,
and in which said recess of each of said members includes a duality
of portions extending between said tabs,
said recess portions being shaped as cylindrical segments.
15. A device as recited in claim 14 in which said tabs are shaped
as cylindrical segments.
16. A device as recited in claim 14 in which
each of said tabs has
a forward surface aligned with the entrance of said outside thread
adjacent thereto,
and a rearward surface opposite said forward surface,
said members being positionable prior to said relative rotation to
said mated position with said rearward surfaces of said tabs of one
of said members abutting said rearward surfaces of said tabs of the
other of said members,
the entrance to said inside thread of each of said members being
then adjacent but spaced angularly outwardly of the entrance to
said outside thread of the other of said members.
17. A device as recited in claim 13 including a detent for holding
said members in said mated position,
said detent including cooperable protuberance and recess means,
one portion of which is on said tab and the other portion of which
is on said member within said recess means.
18. A device as recited in claim 17 in which for said detent each
of said tabs is provided with a longitudinal ridge thereon, and in
which said member is provided with a longitudinal recess engageable
by said ridge when said members are in said fully mated
position.
19. A device as recited in claim 1 in which
each of said members includes a substantially radial surface
radially inwardly of said threads,
said sealing means projecting from said radial surface.
20. A device as recited in claim 19 in which said sealing means
includes an O-ring, said radial surface having an annular groove
therein receiving a portion of said O-ring.
21. A device as recited in claim 19 in which
said sealing means includes an integral deflectable lip extending
outwardly from said radial surface and inclined inwardly toward the
axis of each of said members,
whereby said lips can abut when said members are mated and fluid
pressure can be exerted against said lips for urging the same into
interengagement.
22. A device as recited in claim 1 in which at least one of said
members has a counterbore in the opening therethrough at the
opposite end portion thereof for receiving the end portion of a
hose.
23. A device as recited in claim 1 in which
each of said members includes an axially extending annular recess
in the opposite end portion thereof adapted to receive the end
portion of a hose,
said recess having an inner circumferential wall and an outer
circumferential wall,
said inner circumferential wall having groove means therein,
whereby the end portion of such a hose can be deflected into said
groove means upon inward deflection of said outer circumferential
wall for thereby securing said hose to said member.
24. A device as recited in claim 23 in which said members are of
heat softenable plastic material, whereby said outer
circumferential wall can be so deflected inwardly upon the
application of heat and pressure to the exterior of said member
25. A coupling device comprising
a duality of members,
each of said members including an end portion having
a plurality of substantially identical outside threads, and a
plurality of substantially identical inside threads,
said inside and outside threads being fixed relative to each other
with said inside threads being intermediate said outside threads,
and having entrances positioned at different locations such that
when said end portions of said members are brought into engagement
and relatively rotated said outside threads of each of said members
mesh with said inside threads of the other of said members so that
said members assume a mated position.
26. A device as recited in claim 25 in which each of said members
includes
recess means in said end portion thereof.
and a projecting guide element for entry into said recess means of
the other of said members for facilitating said movement of said
members to said mated position.
27. A device as recited in claim 25 in which said threads of said
members so mesh with each other substantially throughout the
lengths thereof and provide thread meshing around the entire
circumference of said members when said members so assume said
mated position.
28. A device as recited in claim 25 in which said outside thread
includes an axially inner surface having an extension which extends
outwardly beyond said entrance to said outside thread and to a
position adjacent said entrance to said inside thread.
29. A device as recited in claim 28 in which said inside thread
includes an axially outer surface on a helix substantially parallel
to the helix of said extension of said axially inner surface of
said outside thread.
30. A device as recited in claim 29 in which said axially inner
surface of said outside thread and said extension thereof are
substantially perpendicular to the longitudinal axis of said
thread.
31. A device as recited in claim 30 in which each of said members
includes two of said outside threads and two of said inside
threads, said entrances to said inside threads being intermediate
said entrances to said outside threads.
32. A hermaphroditic coupling, which comprises:
a first coupling element adapted to be connected to one component
to be coupled,
a second coupling element adapted to be connected to another
component to be coupled, so that said components are connected to
each other when said first and second coupling elements are
interengaged,
said first and second coupling elements having end portions
substantially identical to each other, and
a male thread section and a female thread section provided
at said end portion of each of said coupling elements,
each of said male and female thread sections of each of said
coupling elements having an entrance and extending therefrom for
only a fraction of one revolution,
said male thread section of each of said coupling elements
extending from said entrance thereof to an inner end thereof in
juxtaposition with said entrance to said female thread section
thereof, said female thread section of each of said coupling
elements extending from said entrance thereof to an inner end
thereof in juxtaposition with said entrance to said male thread
section thereof, said male thread section of each of said coupling
elements being at a circumferential position different from that of
said female thread section of the same coupling element,
said male thread section of said first coupling element being
complementary to and shaped to mate with said female thread section
of said second coupling element.
said female thread section of said first coupling element being
complementary to and shaped to mate with said male thread section
of said second coupling element,
said male and female thread sections of both of said coupling
elements being so located and shaped that when said end portions of
said first and second coupling elements are in predetermined
initial rotated positions relative to each other, rotation of said
first coupling element relative to said second coupling element
through less than one revolution will cause said male thread
section of said first coupling element to mesh with said female
thread section of said second coupling element, and will also cause
said female thread section of said first coupling element to mesh
with said male thread section of said second coupling element,
thereby interengaging and closing the coupling.
33. The invention as claimed in claim 32, in which each of said
coupling elements has two of said male thread sections and two of
said female thread sections, each of said thread sections extending
for about one-quarter revolution, said male and female thread
sections of each of said coupling elements alternating with each
other.
34. The invention as claimed in claim 32, wherein said male thread
section on each coupling element is immovably fixed in position
relative to said female thread section on the same coupling
element.
35. The invention as claimed in claim 32, in which said thread
sections are inclined relative to a plane which is perpendicular to
the axis of the coupling, whereby said relative rotation causes
axial movement of said first coupling element relative to said
second coupling element.
36. The invention as claimed in claim 35, in which said components
to be coupled are fluid conduits, and in which seal means
responsive to said axial movement are provided to prevent fluid
leakage from the closed coupling.
37. A hermaphroditic thread coupling, which comprises:
a first coupling element adapted to be connected to one component
to be coupled, and
a second coupling element adapted to be connected to another
component to be coupled, so that said components are connected to
each other when said first and second coupling elements are
interengaged,
said first and second coupling elements having end portions
substantially identical to each other,
each of said coupling elements having at said end portion thereof
an inclined thread wall,
said thread wall forming along one part of its length the side wall
of a male thread sections, and
said thread wall forming along another part of its length the side
wall of a groove which is part of a female thread section.
38. The invention as claimed in claim 37, in which an end of said
male thread section is adjacent an end of said female thread
section.
39. A hermaphroditic coupling, which comprises:
a first coupling element adapted to be connected to one component
to be coupled,
a second coupling element adapted to be connected to another
component to be coupled, so that said components are connected to
each other when said first and second coupling elements are
interengaged,
said first and second coupling elements being substantially
identical to each other,
each of said first and second coupling elements having at one end
thereof a plurality of inclined planes,
each of said inclined planes partially overlapping another of said
inclined planes,
one portion of each of said inclined planes being a surface of a
ridge of a male thread section,
another portion of each of said inclined planes defining a wall of
a groove in a female thread section.
40. The invention as claimed in claim 39, in which one end region
of each of said inclined planes overlaps another of said inclined
planes, in which the other end region of each of said inclined
plane overlaps still another of said inclined planes, said one end
region and said another inclined plane being on opposite sides of a
groove in a female thread section, said other end region and said
still another inclined plane being on opposite sides of a ridge of
a male thread section.
41. The invention as claimed in claim 40, in which the forward ends
of all of said inclined planes are located substantially in a plane
which is perpendicular to the axis of the coupling.
42. A coupling device comprising
a duality of members,
each of said members including an end portion having
an outside thread, and
an inside thread,
said inside and outside threads being fixed relative to each other,
and having entrances positioned at different locations such that
when said end portions of said members are brought into engagement
and relatively rotated said outside thread of each of said members
meshes with said inside thread of the other of said members so that
said members assume a mated position,
said members being configured and arranged such that the outer edge
surfaces of said members are in juxtaposition when said members so
assume said mated position and said members provide a substantially
gap-free exterior.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a coupling.
2. Description of Prior Art
Many quick-disconnect couplings have been devised in the past, yet
none has met all the criteria for a completely satisfactory device
of this type. Many quick-disconnect couplings use sleeves which are
slid axially when the coupling is mated and unmated for activating
the coupling mechanism. These devices are relatively complicated
and expensive, involving springs and a substantial number of parts.
The two coupling sections are different in these designs, so that
they must be mated properly when the coupling is secured. Other
quick-disconnect couplings have involved rotation through a partial
turn in connecting and disconnecting the mating parts. Typically,
this involves projecting L-shaped lugs which are to interengage
when the two coupling parts are mated. The lugs of these couplings
are vulnerable to damage and, when bent, will prevent the coupling
from functioning. Such couplings are relatively expensive in that
they must be machined from metal, not being adapted for molded
construction out of plastic. Sealing is complicated with these
couplings and overtravel normally is required in the functioning of
the detent as the parts are moved axially beyond their ultimate
mated position during the coupling operation. When fully mated, the
exterior of the coupling is not smooth, resulting in spaces between
the lugs which can accumulate dirt and prevent release of the
coupling. Many couplings of the prior art do not provide a smooth
inside joint when the coupling is mated, and may produce a severe
restriction, resulting in resistance to the flow of fluid. Partial
turn couplings, such as shown in U.S. Pat. No. 99,715 and 103,785,
have relatively moving parts on each section, with attendant cost
and difficulty of operation.
SUMMARY OF THE INVENTION
The present invention provides an improved lowcost, universal,
quick-disconnect coupling overcoming all the shortcomings of the
prior designs. It is adapted for molding from plastic and is of
durable and rugged construction. When mated, it presents a
completely smooth exterior surface so that dirt and foreign matter
cannot accumulate in any location. Its interior also is smooth and
of large diameter, so that it affords almost no additional
resistance to fluid flow.
The coupling includes two identical sections, so that there is
never a problem in selecting the proper coupling components for
mating. Each section includes both inside and outside threads,
preferably a dual-lead thread in both instances, with the inside
threads being positioned intermediate the outside threads. Full
meshing is accomplished by only a quarter turn of relative
rotation, with no axial overtravel. Tabs project forwardly from the
end of the coupling member at the entrances to the outside threads,
the member provided with axial recesses intermediate the tabs for
receiving the tabs of the mating component. The tabs provide a
convenient means to guide the coupling sections together so that
they can be rotated to the fully mated position in which the inside
and outside threads of the two members are meshed. They also act as
stops upon reverse rotation of the coupling components prior to
their rotation to the mated position. The tabs also may incorporate
a detent, which may be in the form of a ridge on the exterior of
the tab to mate with a groove formed in the circumferential wall of
the recess.
The seal for the coupling is on an annular surface which is inside
the threads and the tab elements. This surface may have a groove in
which is received an O-ring so that the O-rings of the two mating
coupling components abut and prevent fluid leakage. An alternate
form of seal is an integral lip which projects from the radial
surface and is inclined inwardly. The lips are deflectable so that
they can maintain firm engagement on their outer surfaces when the
coupling is mated. By virtue of their inward inclination, the lips
can be reacted upon by fluid pressure to increase the force with
which they bear against each other, thereby enhancing the sealing
effect.
A hose may be bonded to the opposite end of the coupling member,
being received in a counterbore so that the coupling has a smooth
interior surface. For another connection to a hose, the member may
be provided with an axial recess to receive the hose, the inner
wall of the recess having an annular groove allowing the coupling
member to be softened by a heated tool and deflected inwardly so as
to force the wall of the hose into the annular groove and lock the
hose to the coupling.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the components of the coupling of
this invention, separated from each other;
FIG. 2 is an end elevational view of one of the coupling
members;
FIGS. 3, 4 and 5 are enlarged fragmentary sectional views taken
along lines 3--3, 4--4 and 5--5, respectively, of FIG. 2;
FIG. 6 is a fragmentary side elevational view, partially broken
away, of the coupling with its two components held together, but
prior to rotation to the mated position;
FIG. 7 is a fragmentary side elevational view, partially broken
away, of the coupling in the mated position;
FIG. 8 is a transverse sectional view taken along line 8--8 of FIG.
6;
FIG. 9 is a transverse sectional view taken along line 9--9 of FIG.
7;
FIG. 10 is a longitudinal section view of the mated coupling taken
along line 10--10 of FIG. 9;
FIG. 11 is a fragmentary side elevational view of the coupling
members angularly positioned for rotation to the mated position,
but shown separated from each other for purposes of
illustration.
FIG. 12 is a fragmentary side elevational view similar to FIG. 11,
but with the coupling components angularly positioned as in a mated
condition;
FIG. 13 is a side elevational view of the mated coupling;
FIG. 14 is an enlarged fragmentary sectional view showing an
alternate seal,
FIG. 15 is an enlarged fragmentary sectional view showing the seal
of FIG. 14 with the coupling mated;
FIG. 16 is an enlarged fragmentary longitudinal sectional view of
the coupling embodying a different means for attachment to the
hose, shown in the process of securing the hose to the coupling;
and
FIG. 17 is a view similar to FIG. 16, but with the hose secured to
the coupling.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The coupling of this invention consists of two identical tubular
members 10, used to interconnect the ends of hoses 11 and 12 in the
example shown. The members 10 may be made of plastic having
resilience and a relatively high strength, such as that marketed by
General Electric Company under the trademark LEXAN and the plastic
marketed by E. I. duPont deNemours and Company under the trademark
DELRIN. Each member 10 includes a central opening 13 of circular
cross section interconnecting the rearward end 14 and the forward
end where the elements of the locking mechanism are located. A
counterbore 15 extends inwardly from the rearward end 14, defining
a radial shoulder 16 at its inner end (see FIG. 10). The ends of
the hoses 11 and 12 fit into the counterbores 15 of the two members
10, with the hose ends abutting the shoulders 16. The periphery of
the hose is bonded to the surface of the coupling member 10 within
the counterbore. The wall thickness of the hose approximates the
width of the shoulder 16, so that the inner surface of the hose is
substantially flush with the surface of the bore 13 beyond the
hose.
At their forward ends, the coupling members 10 include both inside
and outside threads which form inclined planes. There are two
identical inside threads 18 and 19, which commence at diametrically
opposed longitudinal shoulders 20 and 21, and extend through arcs
of 90.degree.. Similarly, there are two outside threads 22 and 23
that are diametrically opposite and are 90.degree. segments. The
longitudinal shoulders 24 and 25 at the entrances to the outside
threads 22 and 23, respectively, are spaced midway between the
shoulders 20 and 21. The threads 18, 19, 22 and 23 are square in
shape and are on similar helices.
The flanks of the inside threads 18 and 19 formed by their axially
outer surfaces 26 and 27, respectively, extend radially to the
outer peripheral surface 28 of the member 10. Axially inwardly and
at the root of the inside thread 18 is an inside surface 29 which
is a fragment of a cylinder and provides the member 10 with a
relatively thin wall at that location. A similar surface 30 is
located axially inwardly of the thread 19. The surfaces 29 and 30
have substantially the same diameter as the crests of the outside
threads 22 and 23.
The outer surface 26 of the inside thread 18 continues in the same
helix beyond the inner end of the thread at the shoulder 25,
extending beneath and parallel to the outside thread 23. In a like
manner, the surface 27 of the inside thread 19 has a continuation
beneath the outside thread 22. The extensions of the surfaces 26
and 27 terminate at the shoulders 21 and 20, respectively, and with
the adjacent outside threads define helical grooves. In other
words, the continuation of the surface beyond the outer surface of
one inside thread extends through an additional arc of 90.degree.
to the angular location where the other inside thread begins.
The axially outer surface 32 of the outside thread 22 continues
angularly on the same helix beyond the inner end of the thread 22,
extending beneath and in parallelism with the inside thread 18. The
surface 32, including its continuation, describes a total arc of
180.degree. and has its inner end at the shoulder 25. On the
opposite side of the member 10, the axially outer surface 33 of the
outside thread 23 has a similar extension beneath the inside thread
19, terminating at the shoulder 24. Thus, each outside thread has
an outer surface which continues beneath an inside thread and ends
at the angular location where the other outside thread starts. The
surfaces 26 and 27 are spaced from the outside threads 23 and 22,
respectively, a distance equal to the thickness of the inside
threads 18 and 19. This is the same distance as that between the
surfaces 32 and 33 and the inside threads 18 and 19, and
corresponds to the thickness of the outside threads 22 and 23.
The outside surfaces 26, 27, 32 and 33 of the threads are all flat
and perpendicular to the longitudinal axis of the member 10. The
outer ends of the threads, both inside and outside, fall in the
same plane, which is radial with respect to the coupling member 10.
With the helices of the threads being similar and their arcs
90.degree., the inner ends of the threads likewise are in the same
radial plane.
Projecting axially forwardly from the coupling element 10 are two
diametrically opposed tabs 34 and 35 which are shaped as
cylindrical segments. The tabs 34 and 35 are positioned at the
beginning of the outside threads 22 and 23, respectively, and
extend angularly inwardly a short distance with respect to these
threads. Hence, the forward edge of the tab 34 is formed by the
shoulder 24 that also forms the outer end of the outside thread 22.
The shoulder 25 provides the forward edge of the other tab 35. The
rearward edges 37 and 38 of the tabs 34 and 35, respectively, are
parallel to the edges provided by the shoulders 24 and 25.
Intermediate the tabs 34 and 35 are relatively deep narrow recesses
39 and 40 which extend inwardly axially beyond the inside threads
18 and 19 and terminate in inner end walls 41 and 42 which fall in
a radial plane. The inner and outer circumferential walls 43 and
44, respectively, of the recess 39 are cylindrical segments. The
same is true of the inner and outer walls 45 and 46 of the recess
40. The shoulders 24 and 25 at the entrances to the outside threads
22 and 23 extend axially inwardly to the end walls 41 and 42 of the
recesses 39 and 40, respectively, and act as one end for each
recess. The other ends of the recesses 39 and 40 are formed by
extensions of the tab edges 37 and 38, respectively.
A flat radial surface 47 interconnects the central bore 13 of the
coupling member 10 and the recesses 39 and 40. An annular groove 48
in the midpart of the surface 47 receives an O-ring 49, which
projects above this surface and acts as a seal when the coupling is
secured. The surface 47 is in a plane within which also falls the
surfaces 26 and 27 at the locations of the inner ends of the
outside threads 22 and 23. The surfaces 32 and 33 at the inner ends
of the inside threads 18 and 19 are also in this plane.
Prior to securing the coupling, the entrances to the inside threads
of one coupling unit 10 are placed adjacent to the entrances to the
outside threads of the other coupling unit 10. In the example of
FIGS. 6 and 8, the entrance to the inside thread 18 of the coupling
unit 10 on the left is adjacent the entrance to the outside thread
23 of the other coupling unit on the right. Also, the entrance to
the inside thread 19 of the latter coupling unit 10 can be seen
next to the entrance to the outside thread of the coupling unit 10
located to the left in this view. In this position, the outer
surfaces of the inside threads are brought into engagement with
each other and, similarly, the outer surfaces of the outside
threads are pressed together. As illustrated in FIG. 6, the
surfaces 26 and 27 of one coupling unit 10 engage the surfaces 26
and 27, respectively, of the other. This brings the outer surface
32 of the coupling unit 10 shown on the left into engagement with
the outer flank surface 33 of the outside thread 23 of the other
coupling section 10 shown on the right. When this is done, the tab
34 of each coupling section 10 enters the recesses 40 of the other
coupling section 10. Similarly, the tab 35 of each coupling section
received in the recess 39 of the other section. These tabs, by
fitting within the recesses, help guide in two coupling sections to
assume an axially aligned position.
The coupling is most easily prepared for rotation to the secured
position by first being given reverse rotation as the two sections
are pushed together, so that the rearward edges of the tabs are in
abutment. With the parts assembled in the manner shown in FIGS. 6
and 8, this brings the rearward edges 37 of the tabs 34 into
contact with the rearward edges 38 of the tabs 35. The tabs are
proportioned such that, when the rearward edges are so in
engagement, there is a small gap between the entrances of the
threads that are to be meshed when the coupling is mated.
With the end faces of the coupling sections held together, they are
then rotated relative to each other for just over a quarter turn,
bringing the coupling to its fully mated position, as shown in
FIGS. 7 and 9. (For purposes of illustration, the left-hand
coupling section 10 is shown in the same position in FIGS. 6-9,
while the right-hand coupling section 10 is rotated in mating the
coupling.) The outside thread 22 of the left-hand coupling section
10 meshes with the inside thread 19 of the coupling section
positioned to the right, while the outside thread 23 of the left
coupling section meshes with the inside thread 18 of the other. The
rotation brings the shoulders at the entrances to the outside
threads and the forward edges of the tabs into abutment. That is to
say, the shoulders 25 of the two coupling halves are brought into
interengagement, as are the shoulders 24. Also, the shoulders 20 at
the outer ends of the inside threads 18 are engaged by the
shoulders 21 at the entrances to the inside threads 19 when the two
coupling halves are brought into interengagement by being rotated
from the position of FIGS. 6 and 8 to that of FIGS. 7 and 9. The
inside threads enter the helical grooves formed by the outside
threads and the extensions of the flank surfaces 26 and 27 of the
inside threads. The outer flank surfaces 26 and 27 of one coupling
section 10 engage the continuations of the flank surfaces 26 and 27
of the other coupling section when the coupling is mated. As a
result of this, the coupling is entirely closed off from the
outside when mated, leaving no gaps or openings. The entire lengths
of the threads are in engagement and concealed, protected from any
injury when the coupling is secured. The long area of thread
engagement gives strength to the assembled coupling.
When the coupling is mated, the radial surfaces 47 of the two
sections are brought into adjacency. This causes the O-rings 49 to
press against each other and form an effective seal. The inside of
the mated coupling is smooth, with no restrictions to the free flow
of fluid. The full diameter of the hoses 11 and 12 is maintained
throughout the length of the coupling.
Rotation of the coupling members 10 in mating and separating the
coupling is facilitated by longitudinal grooves 50 in the outer
surface 28 of each coupling member. These grooves allow the
coupling members to be gripped more securely, and have the added
advantage of conserving material.
A detent is provided to hold the parts in the mated position. The
detent may be simply longitudinal ridges 51 and 52 on the two tabs
34 and 35, which are adapted to enter complementary longitudinal
grooves 53 and 54 in the outer circumferential walls 44 and 46 of
the recesses 39 and 40. When the tabs 34 and 35 enter the recesses
39 and 40, the ridges 51 and 52 slide along the outer
circumferential surfaces 44 and 46, deflecting the tabs 34 and 35
slightly inwardly. When the grooves 53 and 54 are reached, the tabs
spring outwardly, forcing the ridges 51 and 52 into their mating
grooves 53 and 54. Reverse rotation will release the detent by
forcing the ridges 51 and 52 out of the grooves 53 and 54, again
allowing the ridges 51 and 52 to slide along the circumferential
surfaces of the recesses as the coupling sections are
unthreaded.
Alternative to the O-ring seals 49, an integral seal may be
provided on the end face 47, as shown in FIGS. 14 and 15. The
integral seal is merely a lip 56 which is thin and deflectable,
projecting outwardly from the outer edge of the surface 47 and
curved so as to incline inwardly. When the two lips 56 are in
engagement, they form a seal, and the fluid pressure within the
coupling bearing against the inner surfaces of the sealing lips 56
urges them more tightly together to enhance the sealing effect. The
radial surfaces 47 are recessed axially a short distance when the
integral seal is used, compared with the O-ring version, so that
they are not quite as close together when the coupling is
mated.
The hose may be attached to the coupling through the arrangement
shown in FIGS. 16 and 17, rather than by bonding. In this
construction, the coupling includes an annular recess 57 at its
rearward end, dimensioned to receive the wall of a hose 58, and may
have a cylindrical outer surface 59 at that end. The annular recess
57 includes a circumferential groove 60 in its inner wall. With the
hose 58 received in the recess 57, a suitable heated tool 61 is
brought into engagement with the outer periphery 59 of the coupling
in radial alignment with the groove 60, locally heating and
softening the material of the coupling. The tool is pressed against
the surface of the coupling to force the softened material inwardly
toward the groove 60. When the material then cools, it has a slight
groove 62 in its outer surface and is deflected inwardly at this
location so as to force the hose into the groove 60, thereby
locking the hose to the coupling. This forms a permanent attachment
between the hose and the coupling.
The foregoing detailed description is to be clearly understood as
given by way of illustration and example only, the spirit and scope
of this invention being limited solely by the appended claims.
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