Patent Description:
The present disclosure relates to tube cleaning and particularly to propelling foam pellets by compressed gas through hydraulic hose, tubes, piping, conduits, and the like for cleaning interior surfaces thereof. The compressed gas used here is preferably chosen from any regularly available gases and mixtures thereof, including but not limited to air, nitrogen, carbon dioxide, argon, and/or helium, or other suitable gases. Compressed gas-propelled foam pellets or projectiles are used for cleaning the interior surface of a variety of conduits including hydraulic and pneumatic lines wherein the foam projectile removes particulate matter, wipes the interior wall, and absorbs surface film. Preferably, for effective cleaning of the interior wall, the projectile is compressible, and its outer diameter is greater than the conduit bore diameter. The projectile acts as a seal against the interior wall such that the full force of the compressed gas is able to move the projectile through a conduit.

Foam projectiles are available in a range of diameters for use in cleaning conduits in a corresponding range of diameters. Foam projectiles are especially useful in certain applications where the tubing to be cleaned has a plurality of sharp bends as in an air handling system or air conditioner.

Handheld pneumatic guns of the type described in <CIT> are used to position a projectile for entry into a conduit, and to propel the projectile through the conduit with compressed gas. A pneumatic gun of this type includes interchangeable nozzles in different sizes to accommodate different size projectiles for application over a range of conduit diameters.

The pneumatic gun includes a pivoting breech ring for interchanging nozzles and for hand loading projectiles one-by-one into the nozzle. In a first position, the breech ring pivots open for breech loading of a projectile into the gun nozzle. The breech ring is then closed manually. By positioning the gun muzzle adjacent a conduit opening and pulling the trigger, an operator can fire a compressed gas charge that propels the projectile through the conduit. When the projectile passes through the conduit, the compressed gas charge is completely dissipated. This loading and firing sequence are repeated for each projectile loaded into the pneumatic gun.

The steps of opening and closing a pneumatic gun breech for each projectile adds to the complexity and time consumed for completing a conduit cleaning work schedule.

In the event a conduit is obstructed or blocked and the projectile travels into but not through a conduit, the compressed gas charge is not dissipated and acts to force the air gun violently away from the conduit opening. Thus, the potential for obstructed conduits presents a safety hazard for an air gun operator and creates a need for fail-safe dissipation of compressed gas charges in these circumstances.

<CIT> ( hereinafter the '<NUM> patent), discloses a pneumatic air gun for conduit cleaning with foam projectiles, comprising a hand grip with actuating trigger, projectile loading chamber with a quick load port, a nozzle, and a compressed gas circuit including an air flow control valve for directing air in propelling a projectile and for dissipating an air charge in the event of a conduit obstruction.

In one aspect of the pneumatic air gun, a projectile loading chamber surmounts the gun's handgrip and includes a quick load port through which projectiles are loaded axially into a nozzle fitted to the front of the projectile chamber, also known as the "breech", and terminating in a tapered nipple. A door or port closure member in the breech chamber is spring- biased to a normally closed position over the port. For loading the gun, foam projectiles are pushed through the port closure into a nozzle, with the closure then returning to closed position. The breech chamber as well as the nozzle interior behind the projectile then receive a compressed gas charge when the trigger is pulled. Compressed gas propels the projectile through a conduit, cleaning its interior wall. Another projectile may then be loaded and fired in the same way. The nozzle is mounted in a pivoting breech ring that terminates the projectile chamber so that the chamber may be broken open" in a manner similar to a double-barrel shotgun for interchange of a range of nozzle and projectile sizes for cleaning conduits in a corresponding range of diameters.

In another aspect of the pneumatic air gun, compressed gas flows from a source through the gun's handgrip and through a trigger-actuated air flow control valve into the breech. In the event pressurized air remains in the gun after firing a projectile, by reason of an obstructed conduit, the air pressure is dissipated backwards through the air flow control valve when the operator releases the trigger. The built-up compressed gas is diverted harmlessly through an exhaust circuit opened as the trigger is released. Trigger release also stops further flow of compressed gas into the gun chamber.

A shortcoming of the '<NUM> patent is that in operation the apparatus is coupled to the tube to be cleaned solely by forcing the nozzle nipple into the end of the tube and holding it there by operator pressure. air pressure is maintained until the trigger is released; thus, if the tube is fully blocked, the apparatus may become instantaneously and uncontrollably decoupled from the tube. This arrangement can be effective in shortening the cycle time for cleaning a plurality of tubes, but it requires close attention in operation. Further, the axial breech loading mechanism, including the port closure mechanism, requires a relatively large projectile loading chamber and a concomitantly large gun housing.

Published German patent application <CIT> discloses one or more compressible sponge plugs that are driven through the hose or passage to be cleaned by the application of compressed air. In the uncompressed condition the sponge plug is larger in diameter than the passage. The diameter of the air jet, which is directed axially at the sponge plug, is smaller than the diameter of the passage. The method is applied to a hose e.g. by the use of an adaptor with compressed air inlet and a downstream compressed air outlet connecting to the hose to be cleaned. In the side of the adaptor is an opening for the insertion of the sponge plug. The opening is sealed off with a cover.

Published US patent application <CIT> discloses an apparatus for the rapid loading, launching and retrieval of foam pellets for tube cleaning. The apparatus uses a block configuration to allow gravity feed and rapid firing of pellets into tubes. The apparatus includes a hopper feeder attachment, which is self-adjusting during pellet jams.

What is needed in the art is a) an improved mechanism for loading a projectile into the breech, ready for firing, and b) an improved mechanism for positive but simple coupling and uncoupling of the nozzle to the tube to be cleaned. This need is met by the system according to claim <NUM>.

The present disclosure discloses various projectile launchers and methods of manufacture and use thereof. For example, some embodiments of the present disclosure are directed to various apparatuses for cleaning the interior surface of a tube by pneumatically firing a projectile and/or fluid (e.g., a liquid, a gas) through the tube.

In some embodiments, there is a system, comprising: a projectile launching apparatus configured for cleaning an inner surface of a tube by forcing a projectile through said tube along said inner surface, wherein said projectile launching apparatus comprising: a) a main body including an exterior surface, wherein said main body containing a breech chamber terminating in an exit port, wherein said breech chamber is provided with a loading port in a side thereof for radially loading said projectile into said breech chamber; b) a slide disposed over said exterior surface of said main body external to said breech chamber, wherein said slide being axially movable between a first position where said loading port is exposed for loading of said projectile into said breech chamber and a second position where said loading port and said breech chamber are sealed; c) an air gun operatively connected to said main body in pneumatic communication with said breech chamber; and d) an exit nozzle connected to said exit port and being connectable to said tube to be cleaned, wherein the exit nozzle comprises a nozzle body having a threaded end connected to the exit port and a hose-barb end, whereby: (i) a hose-coupling is secured to the hose-barb end by a first hose clamp, whereby the projectile launching apparatus is securable to the tube having an entrance end for the tube to be cleaned by inserting the entrance end into the hose-coupling and tightening a second hose clamp, or (ii) a nipple (<NUM>) is secured to the hose-barb end by a first hose clamp, whereby the nipple has a terminal end smaller in diameter than an entrance end of the tube such that the nipple is sealingly insertable into the entrance end before firing of the projectile launcher. The system may be configured such that said main body, said breech chamber, said exit nozzle, and said slide are cylindrical. The system may be configured such that said exit nozzle has a conical inner surface tapering to a diameter smaller than a diameter of said breech chamber. The system may be configured such that said exit nozzle and said exit port are joined by threads. The system may be configured such that said exit port comprises female threads and said exit nozzle comprises male threads. The system may be configured such that said exit nozzle terminates in a cylindrical port. The system may further be comprising: a clamp configured for positively attaching said projectile launching apparatus to said tube to be cleaned. The system may be configured such that said exit nozzle terminates in a nipple that reduces in width in a direction away from said main body. The system may be configured such that said projectile is in a form of a foam pellet. The system may be configured such that said projectile is conformable to said inner surface of said tube. The system may be configured such that said air gun comprises: a) a main housing; b) a hand grip having a trigger mechanism attached to said main housing, wherein said trigger mechanism includes a trigger; c) a fitting in said hand grip configured for receiving a compressed gas from a source; d) a first passage extending from said fitting through said trigger mechanism to said breech chamber; and e) a second passage extending from said breech chamber through said trigger mechanism to an exhaust port in said hand grip, wherein said first passage is opened to said source and said second passage is closed when said trigger is actuated against an internal spring, and wherein said first passage is closed and said second passage is opened when said trigger is released. The system may be further comprising: an assembly connectable to a second end of said tube for arresting said projectile after exiting said tube. The system may be configured such that the assembly includes at least a vented container in hydraulic or pneumatic communication with said second end of said tube. The system may be configured such that said vented container includes a removable cap. The system may be configured such that said assembly includes a hose and a fitting, wherein said hose includes a first end portion and a second end portion, wherein said first end portion is connectable to said second end of said tube, wherein said fitting is disposed in said removable cap configured for receiving said second end portion of said hose. The system may be configured such that said fitting includes a vent port. The system may be configured such that said removable cap includes a vent port. The system may be configured such that said removable cap includes an entry port arranged such that said projectile enters said vented container tangentially to an inner wall of said vented container. The system may be further comprising: an absorbent material disposed in said vented container.

The present disclosure will now be further described, by way of example, with reference to the accompanying drawings, in which:.

Throughout the following description, specific elements are set forth in order to provide a more thorough understanding of the disclosure. However, some embodiments of this disclosure may be practiced without some of these elements. In other instances, well known elements have not been shown or described in detail to avoid unnecessarily obscuring the disclosure. Accordingly, the specification and drawings are to be regarded as illustrative rather than restrictive. It is to be further noted that the drawings may not be to scale.

Note that various terminology used herein can imply direct or indirect, full or partial, temporary or permanent, action or inaction. For example, when an element is referred to as being "on," "connected," or "coupled" to another element, then the element can be directly on, connected, or coupled to another element or intervening elements can be present, including indirect or direct variants. In contrast, when an element is referred to as being "directly connected" or "directly coupled" to another element, then there are no intervening elements present.

As used herein, various singular forms "a," "an" and "the" are intended to include various plural forms (e.g., two, three, four, etc.) as well, unless specific context clearly indicates otherwise.

As used herein, various presence verbs "comprises," "includes" or "comprising," "including" when used in this specification, specify a presence of stated features, integers, steps, operations, elements, or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or groups thereof.

As used herein, a term "or" is intended to mean an inclusive "or" rather than an exclusive "or. " That is, unless specified otherwise, or clear from context, "X employs A or B" is intended to mean any of a set of natural inclusive permutations.

As used herein, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in an art to which this disclosure belongs. Various terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with a meaning in a context of a relevant art and should not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

As used herein, relative terms such as "below," "lower," "above," and "upper" can be used herein to describe one element's relationship to another element as illustrated in the set of accompanying illustrative drawings. Such relative terms are intended to encompass different orientations of illustrated technologies in addition to an orientation depicted in the set of accompanying illustrative drawings. For example, if a device in the set of accompanying illustrative drawings were turned over, then various elements described as being on a "lower" side of other elements would then be oriented on "upper" sides of other elements. Similarly, if a device in one of illustrative figures were turned over, then various elements described as "below" or "beneath" other elements would then be oriented "above" other elements. Therefore, various example terms "below" and "lower" can encompass both an orientation of above and below.

As used herein, a term "about" or "substantially" refers to a +/-<NUM>% variation from a nominal value/term. Such variation is always included in any given value/term provided herein, whether or not such variation is specifically referred thereto.

Features described with respect to certain embodiments may be combined in or with various some embodiments in any permutational or combinatory manner. Different aspects or elements of example embodiments, as disclosed herein, may be combined in a similar manner.

Although the terms first, second, can be used herein to describe various elements, components, regions, layers, or sections, these elements, components, regions, layers, or sections should not necessarily be limited by such terms. Thus, a first element, component, region, layer, or section discussed below could be termed a second element, component, region, layer, or section without departing from various teachings of this disclosure.

Features described with respect to certain example embodiments can be combined and sub-combined in or with various other example embodiments. Also, different aspects or elements of example embodiments, as disclosed herein, can be combined and sub-combined in a similar manner as well. Further, some example embodiments, whether individually or collectively, can be components of a larger system, wherein other procedures can take precedence over or otherwise modify their application. Additionally, a number of steps can be required before, after, or concurrently with example embodiments, as disclosed herein. Note that any or all methods or processes, at least as disclosed herein, can be at least partially performed via at least one entity in any manner.

Example embodiments of this disclosure are described herein with reference to illustrations of idealized embodiments (and intermediate structures) of this disclosure. As such, variations from various illustrated shapes as a result, for example, of manufacturing techniques or tolerances, are to be expected. Thus, various example embodiments of this disclosure should not be construed as necessarily limited to various particular shapes of regions illustrated herein, but are to include deviations in shapes that result, for example, from manufacturing.

Any or all elements, as disclosed herein, can be formed from a same, structurally continuous piece, such as being unitary, or be separately manufactured or connected, such as being an assembly or modules. Any or all elements, as disclosed herein, can be manufactured via any manufacturing processes, whether additive manufacturing, subtractive manufacturing, or other any other types of manufacturing. For example, some manufacturing processes include three dimensional (3D) printing, laser cutting, computer numerical control routing, milling, pressing, stamping, vacuum forming, hydroforming, injection molding, lithography, and so forth. Further, the term "projectile" as used herein refers generically to any object or material, whether solid, liquid, or gas expelled from the projectile launching apparatus described and claimed hereinbelow.

Referring now to <FIG>, a projectile launching apparatus <NUM> comprises a main body <NUM>, a slide <NUM> disposed on an exterior surface <NUM> of main body <NUM>, a first embodiment of a gas gun <NUM> operatively connected to main body <NUM> via a coupling <NUM>, and an exit nozzle <NUM> connected to main body <NUM> via an exit port <NUM> in main body <NUM>. Preferably but not necessarily, main body <NUM>, slide <NUM>, exit nozzle <NUM>, and exit port <NUM> are cylindrical, which may include a right circular cylinder, an oblique circular cylinder or others.

Main body <NUM> is provided with an internal breech chamber <NUM>, preferably cylindrical, which may include a right circular cylinder, an oblique circular cylinder or others, for receiving a projectile <NUM> to be launched. Projectile <NUM> is preferably a soft pellet, such as a urethane foam sponge. Breech chamber <NUM> is open to the exterior of main body <NUM> by a radial loading port <NUM> whereby projectile <NUM> may be entered into breech chamber <NUM>.

Slide <NUM> is preferably a cylinder, which may include a right circular cylinder, an oblique circular cylinder or others, close-fitting on its inner bore to main body exterior surface <NUM>. Axial travel <NUM> of slide <NUM> is limited in a first direction <NUM>, whereby loading port <NUM> is uncovered, by a first stop <NUM> disposed in a first circumferential groove in surface <NUM> that engages a step <NUM> formed in the bore <NUM> of slide <NUM>. Axial travel <NUM> of slide <NUM> is limited in a second and opposite direction <NUM>, whereby loading port <NUM> is covered, by a second stop <NUM> in the form of a retaining ring disposed in a second circumferential groove in surface <NUM> that engages an end <NUM> of slide <NUM>. For example, slide <NUM> may be disposed over the exterior surface of main body <NUM> external to breech chamber <NUM>, where slide <NUM> can be axially movable between a first position where loading port <NUM> is exposed for loading of projectile <NUM> into breech chamber <NUM> and a second position where loading port <NUM> and breech chamber <NUM> are sealed.

First stop <NUM> is a first U-cup containing an O-ring for sealing the forward end of breech chamber <NUM> against the inner surface of slide <NUM>; similarly, a second U-cup and O-ring <NUM> is disposed in a third circumferential groove in surface <NUM> for sealing the rear end of breech chamber <NUM> against the inner surface of slide <NUM>. Preferably, the outer surface <NUM> of slide <NUM> is knurled to improve the grip by an operator when opening and closing the breech chamber <NUM>.

A first embodiment of gas gun <NUM> comprises a housing containing a first passage <NUM> extending between an inlet port <NUM> and an outlet port <NUM>. An inlet fitting <NUM> is disposed in inlet port <NUM> for connection to a source <NUM> of a compressed gas, e.g., air. Outlet fitting <NUM> is disposed in outlet port <NUM> for connecting air gun <NUM> to breech inlet passage <NUM> in main body <NUM>. A valve <NUM>, shown schematically in first passage <NUM>, is activated by pivotable trigger <NUM> to admit compressed gas to breech chamber <NUM> to fire projectile <NUM> from projectile launching apparatus <NUM>. In the event that the target tube is plugged against passage of the projectile, back pressure <NUM> in the tube is relieved via a second passage <NUM>.

Referring now to <FIG>, a second and currently preferred embodiment of an air gun <NUM> is substantially as disclosed in incorporated <CIT>. Hand grip <NUM> is provided with a compressed gas supply passage <NUM> and a pressure relief passage <NUM>, each terminating in a cylindrical valve chamber <NUM> holding a trigger valve assembly <NUM> having a valve slide <NUM> slidably disposed within a valve body <NUM>. Valve slide <NUM> is actuated by trigger knob <NUM> to control the flow of air from compressed gas source <NUM> to breech chamber <NUM>, and, when required, to ambiance. Valve slide <NUM> is fitted with a spring recess <NUM> receiving a coil spring <NUM>.

When air flow control valve assembly <NUM> is in the position shown in <FIG>, flow of compressed gas from supply passage <NUM> through the valve is blocked.

When the trigger is pulled, thereby moving the valve slide to the left in <FIG>, the compressed gas flows (line 122a) through the valve interior and into breech chamber <NUM> to propel a projectile out of the projectile launcher. Simultaneously, O-ring <NUM> seals the valve interior wall from exhaust port <NUM>. When the trigger is released, spring <NUM> urges valve slide <NUM> to return to the rest position shown in <FIG>, wherein the compressed gas supply is again shut off and exhaust port <NUM> is opened, allowing return flow (line 124a) from breech chamber <NUM> through the valve interior into exhaust passage <NUM>.

In the event a compressed gas charge propels projectile <NUM> into a conduit that is blocked preventing passage of the projectile, the air overpressure existing within breech chamber <NUM> represents a potentially hazardous situation for an operator. Allowing the chamber pressure to drop to an atmospheric pressure ends the potentially dangerous condition.

Referring again to <FIG>, and also <NUM> through <NUM>, exit nozzle assembly <NUM> is disposed in exit port <NUM>, preferably via a male/female threaded connection <NUM> (<FIG>) or other conventional connecting arrangement.

In one embodiment, an exit nozzle assembly <NUM> comprises a nozzle body <NUM> having preferably a male-threaded end <NUM> for connection to exit port <NUM> and a hose-barb end <NUM> for receiving a hose/coupling <NUM> secured to hose-barb end <NUM> by a first hose clamp <NUM>. Preferably, nozzle body <NUM> has a conical inner surface tapering to a diameter smaller than the diameter of breech chamber <NUM> such that projectile <NUM> is radially compressed as projectile <NUM> passes through the nozzle body. Projectile launcher <NUM> is secured to a tube <NUM> to be cleaned by inserting the entrance end of tube <NUM> into hose-coupling <NUM> and tightening second hose clamp <NUM>.

Other suitable arrangements for coupling hose/coupling <NUM> to exit port <NUM> and to nozzle body <NUM>, e.g., by compression fittings, screw threads, quick connect, welding, etc., may be used.

In another embodiment <NUM> of an exit nozzle assembly, with respect to first embodiment <NUM>, hose/coupling <NUM> and second hose clamp <NUM> are replaced by a nipple <NUM> preferably secured to nozzle body <NUM> by first hose clamp <NUM>, or by any of the suitable attachment arrangements cited hereinabove. Nipple <NUM> has a terminal end <NUM> smaller in diameter than the entrance end of tube <NUM> such that nipple <NUM> may be sealingly inserted into the entrance end of tube <NUM> before firing of projectile launcher <NUM>. Preferably, the outer surface <NUM> of nipple <NUM> is conically tapered, allowing a single nipple to be used in cleaning a range of tubes having different diameters larger than the diameter of terminal end <NUM>. Preferably, nipple <NUM> is formed of a soft polymer or elastomer or another suitable material to enhance the seal with tube entrance <NUM>. Additionally, a range of sizes of nipples <NUM> may be provided as needed to increase the range of tube sizes that may be cleaned.

Referring now to <FIG>, alternative embodiments <NUM>,<NUM> are shown for catching a projectile and/or fluid and/or debris exiting from tube <NUM>.

Catching embodiment <NUM> comprises a container <NUM>; optionally an absorbent material, such as an oil-absorbent towel <NUM> disposed in container <NUM>; a threaded container lid <NUM>; a fitting <NUM> disposed in an opening in lid <NUM>; a hose <NUM> extending between vented fitting <NUM> and the exit end of tube <NUM>; and a clamp <NUM> for securing hose <NUM> to tube <NUM>. In some applications, hose <NUM> and clamp <NUM> may be eliminated and fitting <NUM> attached directly to the exit end of tube <NUM>. Embodiment <NUM> includes a vent <NUM>, shown as being an element of fitting <NUM>, but may alternatively be formed in any component of the embodiment.

Catching embodiment <NUM> comprises a container <NUM>; optionally an absorbent material, such as an oil-absorbent towel <NUM> disposed in container <NUM>; a threaded container lid <NUM>; a fitting having a first part 408a disposed in a non-central opening in lid <NUM> and a second part 408b engaging first part 408a; a hose <NUM> extending between fitting 408b and the exit end of tube <NUM>; and a clamp <NUM> for securing hose <NUM> to tube <NUM>. In some applications, hose <NUM> and clamp <NUM> may be eliminated and fitting 408b attached directly to the exit end of tube <NUM>. Embodiment <NUM> includes a vent <NUM> and vent shield <NUM>, shown as being an element of lid <NUM>, but insertable into any component of the embodiment.

Catching embodiment <NUM> is distinguished from catching embodiment <NUM> in that fitting part 408a extends through lid <NUM> and includes an elbow bend <NUM> that causes the path of material being caught to be turned to enter container <NUM> substantially tangential to the inner wall thereof.

In operation, inlet fitting <NUM> is connected to compressed gas source <NUM>, then the entrance end of tube <NUM> to be cleaned is entered into hose/coupling <NUM> and clamp <NUM> is tightened. Slide <NUM> is moved toward tube <NUM>, thereby exposing loading port <NUM>. Projectile <NUM> is inserted into breech chamber <NUM> via loading port <NUM>. Slide <NUM> is then moved or axially or laterally slid away from tube <NUM>, thereby closing loading port <NUM>. Catching embodiment <NUM> or <NUM> is attached to the exit end of tube <NUM>. The projectile launcher is now ready to be fired. The trigger is pulled, discharging the projectile <NUM> into and through tube <NUM> into catching embodiment <NUM> or <NUM>. The catching container <NUM>/<NUM> is unscrewed from its respective cap <NUM>/<NUM>, and the captured material is discarded.

Claim 1:
A system, comprising:
a projectile launching apparatus (<NUM>) configured to clean an inner surface of a tube (<NUM>) by forcing a projectile (<NUM>) through the tube (<NUM>) along the inner surface, wherein the projectile launching apparatus (<NUM>) comprises:
a) a main body (<NUM>) including an exterior surface (<NUM>), wherein the main body (<NUM>) contains a breech chamber (<NUM>) terminating in an exit port (<NUM>), wherein the breech chamber (<NUM>) is provided with a loading port (<NUM>) in a side thereof for radially loading the projectile (<NUM>) into the breech chamber (<NUM>);
b) a slide (<NUM>) disposed over the exterior surface (<NUM>) of the main body (<NUM>) external to the breech chamber (<NUM>), wherein the slide (<NUM>) is axially movable between a first position where the loading port (<NUM>) is exposed for loading of the projectile (<NUM>) into the breech chamber (<NUM>), and a second position where the loading port (<NUM>) and the breech chamber (<NUM>) are sealed;
c) an air gun (<NUM>, <NUM>) operatively connected to the main body (<NUM>) in pneumatic communication with the breech chamber (<NUM>); and
d) an exit nozzle (<NUM>) connected to the exit port (<NUM>) and being connectable to the tube (<NUM>) to be cleaned, characterized in that the exit nozzle comprises a nozzle body (<NUM>) having a threaded end (<NUM>) connected to the exit port (<NUM>) and a hose-barb end (<NUM>), whereby:
(i) a hose-coupling (<NUM>) is secured to the hose-barb end (<NUM>) by a first hose clamp (<NUM>), whereby the projectile launching apparatus is securable to the tube (<NUM>) having an entrance end for the tube to be cleaned by inserting the entrance end into the hose-coupling (<NUM>) and tightening a second hose clamp (<NUM>), or
(ii) a nipple (<NUM>) is secured to the hose-barb end (<NUM>) by a first hose clamp (<NUM>) , whereby the nipple has a terminal end (<NUM>) smaller in diameter than an entrance end of the tube (<NUM>) such that the nipple is sealingly insertable into the entrance end before firing of the projectile launcher.