Patent Abstract:
A pressure-relieving safety assembly, comprising a sleeve and collar, protects against human injury and loss of life by blocking flow of fluid from a ruptured high pressure conduit and provides pressure relief for escaping fluid. This pressure-relieving assembly includes a sleeve that encircles the high-pressure line and is secured to, at one or both ends of the line, a coupling. The sleeve is secured to the coupling(s) by a collar having raised portions that provides a path for fluid that has escaped from the conduit at a burst or pin-hole failure location, to flow towards the ends of the conduit, indicating to the user that a conduit failure has occurred. The sleeve lowers the fluid velocity while the path provided by the collar prevents the fluid pressure from building up behind the sleeve.

Full Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of U.S. Provisional Application No. 61/068,538, of the same title, filed Mar. 7, 2008, which is incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates generally to pressurized conduits such as hoses and tubes, more particularly to systems and methods for protecting against human injury and loss of life due to catastrophic failures in the form of bursts or pin-hole failures in such high pressure fluid conduits, and specifically to a sleeve and collar safety assembly that encloses the length of a high pressure conduit. 
     2. Description of the Prior Art 
     As is well known within the hydraulics industry, injury resulting from hose bursts and pin-hole leaks can occur in a matter of milliseconds. Hydraulic systems may operate at very high pressures and a leak of pressurized fluid can penetrate the skin, causing severe tissue damage and burns. 
     Hydraulic hoses, especially those found on construction equipment, tractors and other equipment, are exposed and therefore vulnerable to wear, which can result in leakage and failure. While a protective encasement, or sleeve, can help reduce wear of a hydraulic hose due to abrasion, a sleeve on its own does not prevent high pressure streams from bursting through the sleeve itself. In the past, problems that have affected the design of such systems have included hose pin hole streams or bursts as well as whipping, where an unmitigated flow of fluid from the end of a hose causes uncontrolled movement of the hose and hose end, posing great danger to an operator. Under high operating pressures or heavy weight, the hose and/or fitting can come loose or blow off the hose, causing the end of the hose to whip with great force. 
     In those situations where wear is unavoidable, rigid spiral hose protectors, spiral plastic sleeves and cloth hose sleeves are sometimes used to help prevent wear. Prior nylon protective sleeves comprising mesh tubing can be slid over single hoses or bundles of hoses and held in place with plastic cable ties or other similar fasteners. These sleeves somewhat help to protect hose from wear and may prolong the life of the hose. 
     Protection methods for high pressure fluid conduits such as hydraulic pipe, tube, and hose, are known. Such protection typically includes a tubular encasement that is overlaid on the outer surface of the conduit, extends substantially over the full length of the conduit, and may be attached to one or both distal ends of the conduit. Other hose protection systems involve outer metal armoring with a bonded coupling. These currently available high pressure conduit protection methods and systems do not protect against pressure build up of the escaped fluid behind the encasements. The resulting damage to the encasement and/or subsequent release of a high pressure stream and or mist of dangerous fluid renders the encasement virtually useless for protection to operators or bystanders. Further, some prior available high pressure conduit safety assemblies employ removable fasteners for an encasement surrounding a hydraulic conduit. This is a dangerous situation because should the sleeve become detached from the conduit, the operator would be directly exposed to conduit failure. Also, these methods of hose protections are bulky and highly reduce the flexibility of the hose assembly. In the case of metal enclosures, their bulk and inflexibly render their use impractical in certain applications requiring flexible connection. 
     One example of a flexible protection assembly for high pressure hoses can be found in U.S. Pat. No. 4,345,624 to Rider. Rider attempts to provide protection to equipment operators (and persons standing nearby) by providing a blow-out guard that comprises a double layer of material and wire sheath fixedly attached over an end portion of the hose. The goal of this system in anticipation of a hose burst is to allow the fluid to escape through interstices of the wire sheath, with the intent of reducing the fluid stream to a fine spray. However, inhalation of certain fluids in the form of a spray or mist may be detrimental to one&#39;s health. Further, when the material carried by the hose is at a very high temperature or when the wire sheath suffers wear and/or fails to carry out its intended duty, danger arises without warning. 
     SUMMARY 
     The present invention is directed to systems and methods, which provide operator protection, and preferably a warning, after a high pressure conduit has incurred damage in the form of a burst, pin-hole failure, or other damage. An example of a safety and warning system that provides superior protection of persons operating equipment employing high pressure conduit systems can be seen in embodiments of the present invention. 
     ISO 3457, EN474-1, and similar so called “line of sight” protection standards or guidelines state that for hoses carrying material (a fluid) at a pressure of 725 pounds per square inch (psi) or higher, wherein the hose assembly is located within one meter of an operator, or if the material carried within the hose exceeds 50 degrees Celsius, protection is required. Currently available flexible textile systems that attempt to provide such protection fail to meet these requirements, resulting in the potential for serious injury to operators, or even loss of life when unrestricted high pressure material bursts through any existing protective flexible textile encasement. 
     It would be beneficial to contain any and all material from a hose burst or pin-hole failure so that a person standing nearby would be entirely protected from danger. A hose can unpredictably burst or develop a pin-hole at any location along its length, making protection very challenging. Therefore, it would be beneficial to provide a safety assembly for a hydraulic conduit in which the securement of the encompassing sleeve or encasement is reliable and fixed. However, it would not only be of benefit to shield the hose assembly, but also to reduce pressure build up behind a protective outer hose sleeve to avoid accumulation of material and eventual failure of the sleeve. 
     Whereas there is no provision in the currently available hose protection systems for relieving pressure of fluid that has escaped from a hydraulic hose and builds up behind an encasement surrounding the hose, no protection exists against the imminent burst of the encasement itself and the ensuing high pressure and/or high temperature stream of fluid. The present pressure relief assembly provides pressure relief for escaped fluid from a high pressure conduit such that the escaped fluid hits a sleeve that surrounds the conduit, slows in velocity, and drains toward one or both ends of the conduit, via a channel, preferably provided by a collar. The escaping fluid does not have opportunity to accumulate behind the sleeve, build in pressure, burst through the protective sleeve and pose danger to the operator standing next to the conduit. Rather, the fluid from a pin-hole, or contained burst, drains out of the sleeve at the end portion(s) of the conduit, which in turn alerts the operator to the failure of the conduit. 
     The process of compressing the collar around the sleeve to secure the sleeve fixedly to one or, preferably both, distal ends of the conduit results in at least one raised portion depending on the method used for compression or the tool itself. The raised portion(s) provide(s) the fluid with an escape route. Preferably, the collar is compressed sufficiently to provide secure attachment of the hose to the sleeve, yet has enough structure to provide a channel from which fluid can escape. 
     Any type of compression method can be used to secure the collar to the sleeve. For example, if using a crimping tool, dies having a tapered generally trapezoidal shape in cross-section, may be retracted to produce the raised portion(s). Upon compression of the collar, the “flowing” metal, which follows the shape of the dies&#39; contact surfaces, forms raised portions. Therefore the shape, size, or cross-section of the raised portion is easily variable depending upon the desired use of the present invention. Additional collars could be used, or collars could be attached to one another or “stacked” in an adjacent fashion along certain portions of the length of the hydraulic conduit for additional stability and/or security. 
     An important advantage of the various embodiments of the present invention is that the sleeve is held in place securely, yet just enough of a channel is provided by the raised portion(s) of the ferrule through which fluid from a hose failure can flow. The various embodiments of the present invention are low-cost, simple to manufacture and implement at time of manufacture or as a retrofit, and are lightweight, elegant, and effective. 
     Thus, in accordance with embodiments of the present invention a method of slidably disposing an impervious sleeve over a fluid conduit having a collar disposed on each end secured thereto might include at least partially radially compressing the collar to engage a coupling associated with each end of the fluid conduit so that the sleeve is held securely to the conduit and comprises a channel through which fluid that escapes from damaged portions of the conduit can flow safely to the end portions of the conduit. Other methods of attaching the sleeve can be employed in accordance with the present invention, for example various types of clamps, which may be fashioned to form channel ends. 
     It would therefore be of benefit to provide a system that would decrease the velocity and pressure of the escaping fluid and provide a safe channel through which the escaped fluid could flow. It would also be highly desirable to provide a system that would alert the operator to dangerous fluid escape from the conduit. 
     Thus, a hose system in accordance with the present invention might comprise a high pressure hose, with an impervious sleeve disposed over the hose. This preferably defines an interstitial space between the sleeve and the hose. Also, the impervious sleeve is preferably impervious to streams of high pressure fluid resulting from a pinhole puncture of the hose, and/or capable of containing bursting of the hose, at a pressure above a rated pressure of the hose. Typically, a coupling, or the like is disposed in each end of the hose and in accordance with the present invention a collar is disposed on each end of the sleeve. The collar is preferably compressed to secure the end of the sleeve between the collar and a ferrule that secures the coupling in the end of the hose. This compression also preferably defines ends of a fluid channel, defined by the interstitial space. As discussed above, this fluid channel preferably provides a path for fluid in the interstitial space to flow out of the interstitial space and to thereby also provide an indication of a failure of the hose. 
     Another advantage afforded by embodiments of the present invention is that when failure in a hose is close to the end of the sleeve, the force behind the fluid tends to pull yarn out of the woven matrix of the sleeve material. Thus, sleeve fabric unsupported by the collar tends to fail at the edge. In accordance with embodiments of the present invention, the end of the fabric making up the hose sleeve is supported and such “pull-out” is avoided. 
     The foregoing has outlined rather broadly the features and technical advantages of the present invention in order that the detailed description of the invention that follows may be better understood. Additional features and advantages of the invention will be described hereinafter which form the subject of the claims of the invention. It should be appreciated by those skilled in the art that the conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention as set forth in the appended claims. The novel features which are believed to be characteristic of the invention, both as to its organization and method of operation, together with further objects and advantages will be better understood from the following description when considered in connection with the accompanying figures. It is to be expressly understood, however, that each of the figures is provided for the purpose of illustration and description only and is not intended as a definition of the limits of the present invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are incorporated in and form part of the specification in which like numerals designate like parts, illustrate embodiments of the present invention and together with the description, serve to explain the principles of the invention. In the drawings: 
         FIG. 1  is a partially fragmented environmental view of an embodiment of the present safety and indicator apparatus and system; 
         FIG. 2  is a perspective view of a collar of the present invention, before attachment to a sleeve of the present invention and coupling; 
         FIG. 3  is a standalone perspective view of an embodiment of the collar of  FIG. 2  after the collar has been compressed; 
         FIG. 4  is front view of an embodiment of the collar shown in  FIGS. 2 and 3 ; and, 
         FIG. 5  is a perspective view of an end portion of the pressure relief assembly of  FIG. 1  showing the channel through which pressure-relieved fluid may flow. 
     
    
    
     DETAILED DESCRIPTION 
     Referring to  FIGS. 1 and 5 , embodiment  100  of the present safety and indicator apparatus and system is shown. In various embodiments of the present invention, the high pressure conduit may comprise hydraulic fluid conduits, such as hydraulic hose, line or pipe. However, it should be understood that the present assemblies can be used in conjunction with conduits or bundles of conduits of virtually any type or size including conduits in the farming, heavy duty equipment, aerospace, power, medical, oil, automotive, and other industries. In other various embodiments of the present invention, high pressure fluid in the form of a liquid may be carried by high pressure conduits employing the present invention. However, it should be understood that the present assemblies can be applied to conduits carrying any type of material, including high pressure hydraulic fluids such as synthetic compounds, mineral oil, water and water-based mixtures, or any other material. 
     Referring back to  FIG. 1 , illustrated embodiment of pressure relief assembly  100 , employs an embodiment of the present invention that includes impervious sleeve  108  encircling high pressure conduit  114 , which is attached securely by collar  104  to the conduit, over ferrule  118  of coupling  116 . In the illustrated use of the present invention, pressure relief assembly  100  is disposed on conduit  114 . As noted, pressure relief assembly  100  may comprise a sleeve  108  and collar  102 . Sleeve  108  may comprise a full-length, but preferably otherwise slightly oversized, sleeve, which encircles the entire circumference of conduit  114 , providing an interstitial space between the conduit  114  and the inner surface of sleeve  108 . Sleeve  108  extends along the entire length of conduit  114 , so that a burst, pin-hole failure, or other form of damage to conduit  114  is surrounded by impervious sleeve  108 . Sleeve  108  may be “impervious” in that it may comprise any material with the ability to slow the velocity of a high velocity and/or high-temperature stream or burst of escaping material from a location of damage along the length of conduit  114 . Preferably, this material is impermeable to a point that it only allows contained fluid to seep through the sleeve, with little, or no, discernible energy. As such, sleeve  108  may comprise a woven textile fabric having metal interwound therewithin, a non-textile fabric, a primarily metal-infused fabric, or any other type of fabric. However, preferably, the material comprising sleeve  108  is an impervious material which will stop the stream of fluid produced by a pin-hole puncture or other breach in conduit  114  at an elevated pressure, such as at twice the rated pressure of a hose. Such a sleeve material is disclosed in U.S. patent application Ser. No. 12/040,596, entitled “Line of Sight Hose Cover,” filed on Feb. 29, 2008, the disclosure of which is incorporated herein by reference. As such, the sleeve preferably absorbs the energy of a pinhole hose failure or fluid escaping from a hose burst. The sleeve  108  may provide enough interstitial space to form a channel  112 . Sleeve  108  could provide any amount of interstitial space, so long as enough excess sleeve material exists to form a channel  112 . Channel  112  may comprise any size of opening capable of delivering fluid that has escaped from a burst or otherwise damaged conduit along the length of the conduit towards the conduit&#39;s distal end(s).  FIG. 5  shows a lowered velocity stream or trickle of fluid  105  exiting the sleeve  108  through channel  112 . As discussed in greater detail below, this trickle of fluid acts as a warning to an operator that the subject conduit has experienced a failure. 
     Sleeve  108  is affixed to the conduit  114  by a collar  102 . Collar  102  may comprise a ferrule-like band such as shown in  FIG. 2 , which may be swaged or crimped to snugly and concentrically encircle the sleeve  108  and attach it to the conduit  114 , such as illustrated in FIGS.  1  and  3 - 5 . The collar  102  may be disposed at any point along a ferrule  118 . In typical hydraulic conduit construction, a coupling, such as illustrated as coupling  116  may have threaded portion  115 , wrenching flat portion  113 . The other end of coupling  116  would typically include stem  117 , insertable into the end of conduit  114 . Threaded portion  115  allows other components to be attached to the conduit  114  to close a hydraulic circuit. To secure stem  117  in conduit  114  ferrule  118  is concentrically affixed about the conduit, typically by crimping, rolling, swaging, or other compression methods. Ferrule  118  may comprise carbon steel, stainless steel, Monel, cast iron, titanium, nano materials, aluminum, brass, and other machinable alloys as well as certain plastics such as resin polymer material. The contrast of the tough material of the ferrule  118  with the sometimes flexibility of a fluid conduit  114  such as a hose cause a weak point in the conduit at a location at or near end  119  of ferrule  118 . As such, it is important to avoid additional stresses along conduit  114  at these locations. Therefore, although collar  102  can be positioned at any location along conduit  114 , preferably collar  102  would be disposed at a location along ferrule  118 . Referring back to  FIG. 1 , it would be preferable to terminate sleeve  108  at or near nut  113 , to ensure that the entire length of fluid conduit  114  is enclosed. 
     It should be understood by one of ordinary skill that collar  102  may be affixed to conduit  114  and protective sleeve  108  after the sleeve has been placed around the conduit. Conversely, collar  102  may be partially compressed with raised portions  104  already formed before placing the collar  102  onto the sleeve. The collar could then be tightened over the sleeve once it has been properly positioned over ferrule  118 . 
     Turning again to  FIG. 1 , the collar  102  may comprise any material, including metal or metal alloy such as aluminum, or steel, brass, copper, polymer, composite, brass, or any other material that can securely retain the sleeve  108  to the ferrule  118 . The collar  102  may comprise raised portions  104  which may help define channel  112  by providing an end of channel  112 . The seams  110  of sleeve  108  may provide a natural location for channel  112 . However, it should be understood that by virtue of providing a raised portion  104 , the collar  102  preferably creates a low-pressure fluid escape path or channel  112  no matter its circumferential location around the sleeve  108 . Collar  102  may be affixed to the ferrule  118 , with sleeve  108  therebetween, by any method that will create a secure fitting between the collar  102 , sleeve  108 , and ferrule  118 . For example, collar  102  can be attached to ferrule  118  by crimping, swaging, rolling, or other compression methods, or by using hand tools. Another method of creating or attaching a collar could be injection molding of the collar around the ferrule and forming the channel ends discussed below through this molding. As a further alternative, the collar may be secured by over-molding a metal, plastic, or other type of collar. Because the diameter of ferrule  118  determines the inside diameter of the collar  102 , it is preferable to provide a compression tool sized correctly for the particular size of conduit  114 . Any method can be used to attach collar  102  to ferrule  118  depending upon the availability of tooling as well as the intended function of the present embodiment and intended dimension and shape of collar  102 . Raised portions  104  are shown as relatively pronounced. However, raised portions  104  may be less pronounced and still provide the desired channel end. Further, only two raised portions  104  are shown. However, any number could be formed. 
     A goal of the pressure relief assembly  100 , which is the safety and well-being of persons standing nearby and/or operating or maintaining the hydraulic system, commonly known as line of sight protection, is achieved by providing a secure means of attachment of the sleeve to the conduit, penetration resistance by sleeve  108 , and preferably a pressure relief path for escaping fluid. As such, other embodiments of collar  102  can be contemplated. For example, collar  102  may comprise pinch or ear clamps, or any other type of clamp. Conversely, collar  102  may comprise a very wide collar or band, having various thicknesses, shape and/or size of raised portions  104 , and composition. An advantage of using a formable collar  102  is that it is a standalone, continuous, effective component that requires no additional fasteners such as screws, ties, or other fasteners, making use of the collar  102  simple, easy, efficient, and cost-effective, which may be crimped using a number of different methods and/or mechanisms. 
       FIG. 2  shows an embodiment of uncompressed collar  102 ′ before compression for attachment to sleeve  108  and ferrule  118 . Referring to  FIG. 2 , uncompressed collar  102 ′ has a smooth inner surface  124  and a smooth outer surface  122 . Again, uncompressed collar  102 ′ may comprise any type of material, including any formable or workable material such as metals, certain composites, some ceramics, glassy-metallics, shock and impact absorbing materials, noise or vibration reducing materials, high-strength polymers, or any other type of material capable of providing secure attachment of sleeve  108  to collar  118 . In certain embodiments the collar might have ridges or shallow teeth defined on inner surface  124 . When the uncompressed collar  102 ′ is compressed around ferrule  118 , preferably the material of the collar  102 ′ will flow along a path of least resistance and may flow in a uniform manner resulting in a more-or less homogenous collar  102  having raised portions  104 . This may be accomplished in accordance with the present invention by only partially compressing uncompressed collar  102 ′, as described in greater detail below. 
     As shown in  FIG. 3 , uncompressed collar  102 ′ is formed by compression methods into collar  102  having raised portions  104 .  FIG. 3  illustrates the compressed shape of collar  102 . In embodiments of the present invention, a crimping or swaging tool having retractable dies can be used to compress the collar onto the conduit  114 . Such a crimping or swaging tool might have any number of dies. Many such crimping or swaging tools have six or eight dies. To create raised portions  104 , one or more dies may be retracted to a desired distance that may be directly proportional to the resultant height of the raised portion  104  (embodied by side  130  of raised portion  104  in the illustrated embodiment). The illustrated embodiment may be created by retracting two dies. Outer surface  134  of raised portion  104  comprises a smooth, relatively even surface illustrating even distribution of the material of compressed collar  102 . In embodiments of the present invention, uncompressed collar  102 ′ is compressed in a compressed location  106  and not compressed in raised portion  104  by virtue of retracting two dies in a crimping tool, resulting in raised portions  104 . An advantage of the present embodiment is that by compressing the collar  102  directly onto the sleeve  108  and ferrule  118 , the task of both firmly attaching the sleeve  108  to the conduit  114 , and providing channel  112  for escaping fluid to flow, is completed in one step. In typical compression or crimping of ferrule about a stem, all of the dies are used to create a uniform compression of a ferrule, resulting in elongation of the ferrule along the longitudinal dimensions of the body (conduit) that it surrounds. Thusly, upon compression of the collar  102  with a compression mechanism which may comprise retractable portions or dies, the collar  102  may not elongate, because its material traverses the surface of the retracted die. However, elongation still may occur in addition to the creation of the raised portion  104 . Preferably, the material properties of collar  102 ′ are retained or enhanced upon formation of collar  102  through compression methods. 
     Referring to  FIGS. 3 and 4 , raised portion  104  comprises a top portion  128 , whose shape is defined by the surface of the retracted die or forming portion of the compression tool, which may have an arched shape, and indention  126  also created by the compression tool (not shown). In embodiments of the present invention, the resulting indention  126  is an acute angle between compressed portion  106  and the side  130  of raised portion  104 . This angle could be any angle or shape including obtuse angles or other shapes and need not be symmetrical (or tidy). Thus, a raised portion created by hand, with a hand tool, would suffice in accordance in accordance with the present invention. As shown in  FIG. 4 , raised portion  104  has a smooth inner surface  132  and outer surface  134  and has maintained a uniform thickness that is equal to the thickness of the remaining crimped portion  106  of the collar  102  indicating uniformity (homogeneity) and therefore strength of the collar  102 . 
     Since typical crimping machines comprise tapered dies that accommodate the concentric surface of a ferrule, longitudinal lines or ridges may form on the crimped ferrule after crimping as a result of material flow into the spaces between the dies at their tapered end. When compressing a formable or workable metal such as aluminum, however, ridges may not occur since the amount of force required to compress the collar  102  to the ferrule  118  is less than that required to compress a steel ferrule  118  to a conduit  114  for example. A significant advantage of the collar  102  of the present embodiment is that it can be retrofitted in the field because extreme pressure for compression is not needed. When using collars  102  of a relatively soft material, hand tools may be employed, allowing pressure relief assembly  100  to be assembled in a retrofit fashion very quickly, and in the field. 
     In summary, many industries can take advantage of the embodiments of the present safety and indicator apparatus systems and methods for high pressure conduits. The pressure relief assembly  100  comprises a channel that is created by a method of attaching a collar  102  to a protective sleeve  108 . The pressure relief assembly  100  can be applied to any high pressure conduit  104  in a retrofit manner or during production. The resultant protection and warning system is effective for conduits carrying even very high pressure fluids. The warning system preferably prevents injury to the operator and/or damage to the associated equipment, as the operator, upon seeing a trickling stream of fluid coming out of channel  112 , could simply turn off the system. The collar  102  is a standalone product, requiring no fasteners such as those used in pinch clamps. The size, shape, number, and cross section of the raised portion of the collar  102  can be varied depending upon the intended use of the present embodiment as can the desired unit cost. The raised portion  104  and the uncompressed collar  102 ′ can embody virtually any cross section, including square, elliptical, oblong, or oval-shaped cross sections and can vary in size, shape, diameter, weight, thickness, width, or height. For example, one might envision a narrower initial collar  102 ′ or a shorter raised portion  104 . The diameter of the uncompressed collar  102 ′ can vary depending upon the size of the conduit  114  and/or its overlaying sleeve  108 . The material of the collar  102  would preferably comprise flow properties that would allow it to conform to the shape of the compression tool and retain strong molecular structure, although many materials may be contemplated in the construction of both the sleeve  108  and the collar  102 . 
     Although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims. Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification. As one of ordinary skill in the art will readily appreciate from the disclosure of the present invention, processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized according to the present invention. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps.

Technology Classification (CPC): 5