CA1209171A - Coupling for fluid flow system - Google Patents

Abstract

COUPLING FOR FLUID FLOW SYSTEM
ABSTRACT OF THE DISCLOSURE
A detachable coupling for connecting a fire hydrant barrel to a fire hose includes a socket in the barrel and a nozzle permanently but replaceably mounted in the socket. The socket has radially inwardly extending coupling lugs, and nozzle has radially outwardly extending coupling flanges. To mount the coupling nozzle in the barrel socket, the socket is selectively inserted into an opening in the socket with the lugs and flanges so aligned that the nozzle flanges pass by the socket lugs. The nozzle is then rotated to axially align the lugs and flanges.
Releasable locking means constituted as a locking ring threadably mounted on the nozzle is used against the socket to draw the nozzle lugs back into overlying locked relation with respect to the flanges. A
resilient O-ring seal is also provided in the locking ring between the socket and nozzle to prevent leakage between the coupling and the hydrant barrel.

Description

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COUPLING FOR FLUID FLOW SYSTEM
_ BACKGROUND OF THE INVENTION
.
1. Field of the Invention.
.
The present invention relates to fluid flow system couolers, and specifically to a detachable coupling for connecting a vessel such as a fire hydrant barrel and a conduit such as a fire hose

2. Description of the Prior Art.
There are numerous couplings for connecting portions of fluid flow systems in the prior art. In some applications, ease of repair or replacement to damaged or worn couplings is of critical importance.
In particular, this is the case with respect to fire hydrants and the couplings mounted thereon. Once a fire hydrant has been placed in service, it is not easily removed for repair or replacement of portions of the hydrant. because many hydrants must be placed adjacent areas of high vehicle traffic, the chance for such damage occurring over their service life is great.
Typically, the body or barrel of a fire hydrant is cast iron in construction. As shown in U.S. Patents 3,692,042 to Dashner, granted September 19, 1972; and 4,141,574 to Stansifer et al, granted February 27, 1979, the nozzle receiving sockets on such cast iron hydrant barrels are machined and threaded for acceptance of a nozzle upon which a fire hose or nozzle cap can be placed. This hydrant design is also shown in a flyer by the Clow Corporation of Oskaloosa, Iowa entitled "Features of the Clow Contemporary Hydrant." The machining of such large and bulkly cast iron parts is exPensive and time consuming. Damage to the threads of a fire hydrant made in this manner requires replacement or remachining of the nozzle, a difficult and expensive task requiring considerable equipment.

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One attempt to alleviate this machining and field repair problem is discussed in the January 4, 1982 issue of Desian News, pages 84-85. Some fire hydrants are manufactured with the nozzle assemblies sealed in the cast iron hydrant barrels with molten lead. To replace a damaged nozzle secured to a hydrant in this manner also required a considerable amount of time and expense. According to the Design News article, Waldes Kohinoor, Inc., of Long Island City, New York, produces a fire hydrant nozzle which is not screwed or sealed intn the hydrant barrel, but retained in a nozzle opening in the barrel by an external-type retaining ring. A major drawback of this design is that the nozzle must be inserted from the inside of the hydrant barrel to position it in the nozzle opening. In addition, to properly insert or remove such a nozzle from a hydrant, a hydraulic ram or yoke puller is required and a special retaining ring pliers is necessary to manipulate the retaining 2û ring.
Another form of nozzle which is secured to a fire hydrant without the hydrant being threaded is the AMLOK nozzle for use on the AMERICAN B-62-B hydrant and manufactured by American Valve and Hydrant of Birmingham, Alabama. This nozzle does not require threading of the hydrant barrel, but it is still necessary to machine certain portions of the hydrant barrel for acceptance of the sealing surface of the nozzle. The AMLûK noz71e has locking lugs in both the nozzle and fire hydrant socket for mainiaining the nozzle on the socket. A separate steel pin is provided to prevent rotation of the nozzle once 7 nstalled in the hydrant barrel. Normal insertion of the AMLOK nozzle sometimes fails to positively seal the nozzle against the hydrant barrel. Because of this, American Valve and Hydrant furnishes a spacer 12~9~1 with each replacement nozzle which can be placed between the nozzle and the hydrant barrel socket.
Rising labor costs, both in the initial manufacturing stages and for repair, greatly diminish the economical efficiency of the various hydrant coupling configurations described above. None of these prior art devices discloses a detachable replaceable coupling for use with a vessel (such as the barrel of a fire hydrant) in which the vessel proper needs no machining and the coupling can be easily replaced without removing the vessel from its regular location.
SUMMARY OF THE INVENTION
The present invention presents a detachable coupling for connecting a vessel having an open socket with a conduit of a fluid flow system The coupling includes a generally cylindrical nozzle which can be connected to a conduit in any usual or preferred manner. The nozzle can be inserted into a circular opening provided by the vessel socket. The socket has a plurality of radially extending and spaced apart coupling lugs. At a first end, the nozzle has a plurality of radially extending and spaced apart coupling flanges. When this first end of the nozzle is inserted into the socket opening, the flanges are carried axially past the lugs. The nozzle is rotatable after insertion so that each coupling flange is aligned upon one of the coupling lugs. Positioned outside of the socket is a releasable locking means operative on the nozzle and socket to force the nozzle axially outwardly from the socket so that the coupling flanges are drawn against the coupling lugs. Means are provided for preventing rotation of the nozzle with respect to the socket when the coupling flanges are drawn against the coupling lugs, and sealing means between the nozzle and the socket prevents leakage between the vessel and the coupling.

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BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevational view of a fire hydrant having at least three detachable couplings of the present invention mounted thereon;
FIG. 2 is an enlarged fragmentary vertical sectional view taken along line 2--2 of FIG. 1 illustrating a first embodiment of the invention;
FIG. is an enlarged fragmentary vertical sectional view taken along line 3--3 of FIG. 2;
FIG. 4 is an enlarged sectional view also taken on the line 2--2 of FIG. 1, but showing a detachable coupling with nozzle aligned for insertion into a socket of a hydrant barrel;
FIG. 5 is an enlarged fragmentary vertical sectional view taken along line 5--5 of FIG. 4;
FIG. 6 is a fragmentary sectional view taken along line 6--6 of FIG. 3;
FIGS. 7A and 7B are an enlarged fragmentary sectional view of an O-ring cavity formed by a locking collar on the coupling nozzle and of an O-ring in that cavity as seen at the bottom of the coupling nozzle in FIGS. 4 and 2, respectively, and illustrating the relationships and operation of those elements and of a hydrant barrel socket in sealing the coupling to the socket; and FIG. 8 is an exploded side elevational view with parts in section and parts broken away of a second form of the present invention showing a coupling with nozzle aligned for insertion into a socket of a hydrant barrel and showing a fire hose aligned for attachment onto the nozzle.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The following description of the present invention is in terms of a detachable coupling positioned on a fire hydrant. However, it is understood that the coupling of the present invention ~2~917~

is suitable for use in a number of other fluid flow systems, such as pumps, valves and pipelines.
A fire hydrant 10 has a vessel or barrel 12 secured upon a standpipe 14. As shown, sockets 16 are provided on the barrel 12 for connecting fire hoses to the fire hydrant lû. In the usual case, the barrel 12 is provided with a pumper or engine socket 18 for connection of the hydrant 10 to a fire engine or pumper (not shown) and is provided with at least one hose socket 20 for connection to a fire hose to deliver water to a fire.
A detachable coupling 22 of the present invention is shown mounted on the barrel 12 of the fire hydrant in FIG. 2. The coupling 22 connects the barrel with a conduit of a fluid flow system to allow fluid (not shown) to flow from the barrel 12 into the conduit, or vice versa. The coupling includes a nozzle 24 which, as shown in FIGS. 2 and 3, is insertable into a circular opening 26 provided in the socket 18. The nozzle 24 is generally toroidal and, at a first interior end portion 30 thereof, includes a plurality of radially outwardly extending and spaced-apart coupling flanges 28. See FIGS. 3 and 5.
Each coupling flange 28 is provided with an exteriorly facing slide surface 32. The nozzle 24 also has an annular insertion stop shoulder 34 concentric with , outside of and set back from its first end portion 30. The socket 18 of barrel 12 has a plurality of radially inwardly extending and spaced apart coupling lugs 36 extending into its circular opening 26. See FIGS. 3 and 5. Each coupling lug 36 has an interiorly facing surface 38 and an opposite exterially facing surface 40. A plurality of gaps 42 are defined in the opening 26 as being the space between adjacent coupling lugs 36 proximate the periphery of the circular socket opening 26.

~Z(~'7i To insert the nozzle 24 of coupling 22 into the opening 26 of the socket 18, the nozzle is placed in an insertion position so that each of its flanges 28 is axially aligned with one of the gaps 42 between the lugs 36 (as seen in FIGS. 4 and 5). The nozzle 24 is then inserted into the opening 26 of the socket 18. In so doing, the coupling flanges 28 pass through gaps 42 and are carried axially past the coupling lugs 36 (toward the barrel 12) until the exteriorly facing surfaces 40 of the lugs 36 abut the insertion stop shoulder 34 on the nozzle 24. At this point, the exteriorly facing slide surfaces 32 of the flanges 28 have cleared the interiorly facing surfaces 38 of the lugs 36 so that rotation of the nozzle 24 in the socket 18 is possible. To place the nozzle 24 in position for coupling, it is rotated in the direction of arrows 44 in Figures 5 and 6 until each flange 28 is aligned with one of the lugs 36 as shown in Figure

3.
2û Detachable coupling 22 includes a releasable locking means 45 which locks the nozzle 24 in fixed relationship with respect to the socket 18 by forcing the nozzle axially outwardly from the socket 18 so that the flanges 28 are drawn against the lugs 36.
The releasable locking means includes a locking collar 46 which is threadably mounted on the nozzle 24, as shown in FIGS 2 4, 7A and 7B. Preferably, the locking collar 46 is cylindrical and has a first interiorly facing socket engaging surface 48 at one side thereof. A resilient O-ring 5û is positioned on the nozzle 24 to seal the coupling 22 to the hydrant barrel 12 when the nozzle 24 is locked to the socket 18. The O-ring 50 is seated in an annular O-ring cavity 52 which is disposed between the socket 18 and the nozzle 24. Preferably, the O-ring cavity 52 is in the locking collar 46, as best shown in FIGS. 7A and 12~9'~

7B. As shown, 0-ring cavity 52 is defined by an outer cylindrical surface 54 of the nozzle 24, and beveled surface 56, plane radially extending surface 58 and cylindrical surface 60 of the locking collar 46.
To lock the nozzle 24 onto the socket 18, with the parts as shown in FIG. 3 but positioned as shown in FIG. 7A, the locking collar 46 is rotated so that the socket engaging surface 48 of the locking collar is forced against an outer peripheral surface 62 of the socket 18. Further rotation of the locking collar 46 on the nozzle 24 causes exteriorly facing slide surfaces 32 of the flanges 28 to be drawn against the interiorly facing surfaces 38 of the lugs 36. When the locking collar 46 is fully tightened on the nozzle 24, axial movement of the nozzle 24 with respect to the socket 18 is effectively prevented.
FIG. 7A shows the relationship of the 0-ring 50 to other associated elements with the nozzle 24 fully inserted into the socket 18, but prior to locking the nozzle onto the socket. As shown, the 0-ring 50 is dimensioned so that a portion of the 0-ring 50 extends outwardly from the 0-ring cavity 52. FIG. 7B shows the deformation of the 0-ring 50 when the nozzle 24 is locked on the socket 18. This deformation provides a positive seal between the surface 62 of the socket 18 and surface 54 of the coupling 22. Fluid pressure existing inside the hydrant barrel 12 acts on the 0-ring 50 to force it into even firmer sealing relation to surfaces 62 and 3û 54.
In FIG. 2, the nozzle 24 is shown locked onto the socket 18 of the barrel 12. The locking collar 46 is threadably advanced on the nozzle 24 so that socket engaging surface 48 and outer peripheral surface 62 are pressed together. The coupling flanges 28 on the nozzle 24 are drawn back out against the ~2~9~

coupling lugs 36 of the socket 18, and the 0-ring 50 is deformed to prevent leakage at the coupling.
Rotation limiting and preventing means are provided to properly align and then prevent further rotation of the nozzle 24 with respect to the socket 18 as the coupling flanges 28 are drawn against the coupling lugs 36. qt least one of the couPling lugs 36 has a stop shoulder 64 at a first end portion 66 thereof and a slide shoulder 68 at a second end portion 70 thereof. The stop shoulder 64 and slide shoulder 68 extend axially of the coupling lug 36 inside the barrel 12, as shown in Figures 4 and 6.
Stop shoulder 66 extends further axially inside of the barrel 12 then does slide shoulder 68, as best shown in Figure 6.
Upon insertion of the nozzle 24 into the socket 18 and rotation thereof, flange 28 as shown in phantom in Figure 6, rotates with the nozzle 24 until it contacts stop shoulder 64 on the lug 36. In so doing, the flange 28 passes or slides over the slide shoulder 68, with the exteriorly facing slide surface 32 of the flange 28 passing across an interiorly facing slide surface 72 on tne slide shoulder 68.
Slide shoulder 68 does not extend axially far enough inside of the barrel 12 to interfere with the rotational movement of the flange 28 when the nozzle 24 is fully inserted into the socket 18. However, the extra axially extension of stop shoulder 66 does prevent rotational movement of the flange 28 even when the nozzle is fully inserted. As stated, in Figure 5, arrows 44 illustrate the direction of rotational motion of the nozzle 24 and flanges 28 over slide shoulder 68 and onto lugs 36~
nnce the nozzle 24 is rotated in the socket 18 such that the flange 28 contacts stop shoulder 66, the nozzle is properly rotationally aligned for 12~9~1 _ 9 locking onto the socket 18~ This radial positioning is shown in Figure 3. As best shown in Figure 6, the stop shoulder 66 and slide shoulder 68 act together to define a recess 73 on the interiorly facing surface 38 of the lug 36. This recess is formed for acceptance of the coupling flange 28 when the nozzle 24 is moved outwardly in the process of releasably locking it onto the socket 18. Rotation of the locking collar 46 on the nozzle 24 urges the nozzle 24 outwardly from the socket 18 so that the slide surface 32 of the flange 28 is drawn against the interior surface 38 of the lug 36. In so doing, flange 28 is seated in the recess 73 on the lug 36 so that rotational movement of the nozzle 24 is prevented by stop shoulder 64 and slide shoulder 68, as shown in Figures 3 and 6.
Removal of the nozzle 24 from the socket 18 is effected by simply reversing the process. The locking collar 46 is rotated on the nozzle 24 in direction to move it away from the socket 18 a sufficient amount so that the nozzle 24 can be moved axially allowing the exteriorly facing slide surface 32 of the flange 28 to clear the interiorly facing slide surface 72 of the slide shoulder 68. The nozzle 24 is then rotated to position as shown in Figure 5 and withdrawn from the socket 18.
In the first embodiment of the present invention, the nozzle 24 (as shown in Figures 2 and 4) has a first externally threaded portion 74 upon which the locking collar 46 is threadably mounted and a second externally threaded portion 76 more proximate a second end portion 78 of the nozzle 24. The second threaded portion 76 has separate distinct threads from those of the first threaded portion 74. The second threaded portion 76 is provided on the nozzle 24 for attaching other portions of the fluid flow system (such as a conduit or hose) on the coupling 22. In 126~9~L7~

addition, the second threaded portion 76 provides means for securing an internally threaded nozzle cap 80 on the second end portion 78 of the nozzle 24 as shown in Figure 2. A gasket 82 is placed between the nozzle 24 and the nozzle cap 80 and the nozzle cap is threadably mounted on the second threaded portion 76 of the nozzle. This is to prevent leakage between these two elements and thus seal off the coupling 22 until it is needed.
A second embodiment of the detachable coupling of the present invention is shown in Figures 1, 2 and 8. As stated, the usual fire hydrant 10 has a barrel 12 with at least one hose socket 20 provided thereon. Each such hose socket is provided with a generally circular opening 84. A detachable coupling 22 includes a nozzle 86 which is insertable in the opening 84 of the socket 20.
The nozzle 86 is generally toroidal and, at a first interior end portion 90 thereof, includes a pair of radially outwardly extending and spaced-apart coupling flanges 88. See FIGS. 2 and 8. The nozzle 86 also has a raised annular band 92 providing an annular insertion stop shoulder 94 spaced from the first end portion 90 of the nozzle. The socket 20 has a plurality of radially inwardly extending and spaced-apart coupling lugs 96 extending into its circular opening 84. A pair of gaps 98 are defined in the opening 84 as being the space between adjacent lugs 96 proximate the periphery of the opening 84.
As in the previous embodiment, the flanges 88 are aligned with the gaps 98 and the nozzle 86 is inserted into the opening 84 in the socket 20 until the flanges 88 are carried axially past the lugs 96.
When fully inserted, the insertion stop shoulder 94 of the nozzle 86 abuts outer outwardly facing peripheral surfaces 100 of the coupling lugs 96. The nozzle 86 is then rotated in the socket 20 to align the flanges 88 upon their respective couplin0 lugs 96 for locking, as shown in Figure 2.
A locking collar 102 is threadably mounted on the nozzle 86 to provide a means for locking the nozzle onto the socket 20. When the nozzle 86 is positioned in the socket 20 for locking (as in Figure 2), the locking collar 102 is advanced on the nozzle 86 to draw the flanges 88 against the coupling lugs 96. In so doing, an interiorly facing socket engaging surface 104 on the locking collar 102 is pressed against an outer peripheral surface 106 of the socket 20.
To seal the coupling 22 to the hydrant barrel 12 when the nozzle 86 is locked on the socket 20, a resilient 0-ring 108 is mounted in an 0-ring cavity llû between the locking collar 102, the outer surface of annular band 92 and the socket 20. The 0-ring cavity 110 has a beveled portion 112 to retain and maintain the 0-ring 108 in position for a tight seal. The 0-ring 108 is dimensioned so that a portion of the 0-ring lû8 extends outwardly from the 0-ring cavity llû when the locking collar 102 is in a non-locked position. Upon rotation of the locking collar 102 on the nozzle 86 to tighten against socket 20, the 0-ring 108 is deformed to contact all the surfaces adjacent the 0-ring cavity 110 and seal the coupling 22 to the barrel 12. Fluid pressure inside the barrel further deforms 0-ring 108 to force it even more tightly against surface 106 of socket 20 and the outer cylindrical surface of annular band 92.
At least one of the coupling lugs 96 has a stop shoulder 114 and slide shoulder 116 at opposite ends thereof. The combination of stop shoulder 114, slide shoulder 116 and coupling lug 96 forms a recess 117 on the coupling lug 96 for acceptance of one of lZ~

the flanges 88 as the nozzle 86 is locked on the socket 20. when the flange ~8 is seated in this recess 117, the nozzle 86 is prevented from rotation in the opening 84.
In this second embodiment of the detachable coupling of the present invention, the nozzle 86 is provided with only one externally threaded portion 118. The locking collar 102 is thus threadably mounted on the nozzle 86 from a second end portinn 120 of the nozzle 86, with the extent of movement of the locking collar 102 on the nozzle 86 being limited by the raised annular band 92, as illustrated in Figure 8. As perhaps best seen in FIG. 8, a conduit 121 in this embodiment includes a fire hose 122, and a mounting collar 124 at an inner end of the hose 122.
The mounting collar 124 has an internally threaded portion 125 cooperating with the threaded portion 118 of the nozzle 86. THe conduit also includes a sealing means, such as a gasket 126, mounted between the end of the hose 122 of the nozzle 86. The collar 124 is threadably mounted on and sealed to the nozzle 86 (which, in turn, is locked on the socket 2û) to allow fluid (not shown) to flow from the barrel 12 into the conduit 121.
As shown in Figure 1, a nozzle cap 128 is threadably mounted on the nozzle 86 when the hose 122 is detached.
Conclusion The present invention provides a detachable coupling for connecting a vessel and conduit of a fluid flow system. The coupling, which is useful in many applications, includes a socket in the vessel and a nozzle (insertable in the socket) on the conduit.
The nozzle and socket have a plurality of coupling lugs and coupling flanges, respectively, which are used to align and secure the nozzle in the socket.

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The nozzle can be locked with respect to the socket both axially and rotationally and sealing means are provided to prevent leakage between the socket and the nozzle. A device of this configuration provides a detachable coupling for a vessel where the vessel needs no machining and the coupling can be easily replaced. The use of this coupling reduces labor costs, both in the initial manufacturing stages and during replacement or repair of the coupling.
Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.

Claims (12)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows: :

1. A detachable coupling for connecting a vessel and a conduit of a fluid flow system, the coupling comprising:
a socket in the vessel, the socket having a circular opening and having a plurality of spaced apart coupling lugs each extending radially inwardly in the opening;
a generally cylindrical nozzle on the conduit, a first end of the nozzle having a plurality of spaced apart coupling flanges each extending radially outwardly therefrom, the first end of the nozzle being selectively insertable into the socket opening to carry the flanges axially past the lugs, the nozzle then being rotatable to position such that each coupling flange is aligned upon one of the coupling lugs;
releasable locking means operative on the nozzle and socket outside of the socket for locking the nozzle in fixed relationship with respect to the socket, the locking means forcing the nozzle axially outwardly from the socket so that the coupling flanges are drawn against the coupling lugs; and sealing means between the locking means and socket for sealing the coupling to prevent leakage between the socket and nozzle.

2. The coupling of Claim 1 wherein the socket has an outer peripheral surface being constituted as a sealing surface, and the releasable locking means comprises:
a locking collar threadably mounted on the nozzle, the locking collar having a surface mating with the sealing surface of the socket when the locking collar is positioned on the nozzle so that the coupling flanges are drawn against the coupling lugs.

3. The coupling of claim 2 wherein an annular O-ring cavity is provided between the locking collar and the socket sealing surface and wherein the sealing means comprises:
a resilient O-ring mounted on the nozzle adjacent the locking collar to prevent leakage between the locking collar surface and the socket sealing surface and between the locking collar and the nozzle.

4. The coupling of claim 3 wherein:
a portion of the O-ring cavity is beveled in cross section to retain and urge the O-ring in position to effectively seal the coupling.

5. The coupling of claim 3 wherein:
the O-ring cavity is in the locking collar.

6. The coupling of claim 1 and further comprising:
means or preventing rotation of the nozzle with respect to the socket when the coupling flanges are drawn against the coupling lugs.

7. The coupling of claim 6 wherein the rotation prevention means comprises:
a stop shoulder at a first end of at least one of the coupling lugs of the socket, the stop shoulder extending axially inside the vessel to limit rotation of the nozzle with respect to the socket opening and align the coupling flange upon its respective coupling lug; and a slide shoulder at a second end of said coupling lug of the socket, the slide shoulder extending axially inside the vessel, the stop shoulder and slide shoulder together defining a recess on an inside side of the coupling lug for acceptance of the coupling flange when the nozzle is urged outwardly from the socket opening, and the slide shoulder being dimensioned so that the coupling flange slides passed it upon rotation with respect to the socket opening but limits rotation of the nozzle when the flange is seated in the recess.

8. The coupling of claim 1 wherein:
the vessel includes a fire hydrant barrel.

9. The coupling of claim 1 wherein:
the conduit includes the nozzle, a hose and an internally threaded hose mounting collar at an end of the hose, said collar having a collar sealing means mounted therein, the nozzle being threaded externally proximate a second end of the nozzle, and the hose mounting collar being threadably mounted on the second end of the nozzle to operably seal the hose to the nozzle.

10. The coupling of claim 9 and further comprising:
a nozzle cap for covering the second end of the nozzle when the hose and collar are removed from the nozzle, the nozzle cap being threadably mounted on the second end of the nozzle.

11. The coupling of claim 1 wherein:
the nozzle has a first set of external threads proximate its first end and a separate second set of external threads proximate a second end of the nozzle, the conduit includes the nozzle and a hose, the hose is threadably mounted on the second set of threads on the nozzle, and the releasable locking means includes a locking collar threadably mounted on the first set of threads on the nozzle.

12. The coupling of claim 1 wherein:
a portion of the nozzle is threaded externally proximate a second end of the nozzle, the nozzle has a raised annular band proximate its first end and adjacent the threaded portion, the releasable locking means includes a locking collar threadably mounted on the threaded portion of the nozzle, the extent of travel of the locking collar on the nozzle is limited by the annular band, the conduit includes the nozzle and a hose, and the hose is threadably mounted on the threaded portion of the nozzle adjacent the second end of the nozzle.