Patent Application
20220025999
The present technology pertains to tubings and hoses, and more specifically to the reinforcement of garden and other fluid carrying hoses for improved burst characteristics and pressure cycling performance thereof.
Flexible hoses are commonly used to convey fluids over a wide range of temperatures and pressurizations, both of which may change in accordance with use case and/or environmental conditions. For example, a garden hose might be used to convey water from a relatively high-pressure source such as a municipal water supply or from a relatively low-pressure source such as a cistern; the same garden hose might also be used to convey cold water during early spring and hot water during late summer.
On top of these varying fluid characteristics that garden hoses must be able to handle, hoses are commonly subjected to moderately rapid pressure cycling, i.e., in which the hose is used for many short periods rather than for a prolonged period of time. Such pressure cycling can noticeably increase the wear and tear experienced by hoses and other tubings, or otherwise noticeably reduce their durability, as each pressurization cycle produces a shear force and expansion of the hose wall. Repeated pressure cycling typically leads to a bursting type failure in which the hose wall splits at or near the area which has experienced the greatest amount of shearing force. In conventional garden hoses, this failure point is typically located directly behind the ferrule attached to the open end of the hose.
In conventional hoses, reinforcement is achieved by strengthening the entirety of the hose, along its full end-to-end length. For example, many hoses are manufactured by extruding layers of PVC or other material and wrapping reinforcement yarns between the layers in order to provide greater strength and durability. However, the use of reinforcement yarns can increase manufacturing costs and lead to a hose that is undesirably stiff or rigid, as these yarns obtain better burst performance by sacrificing pliability. Some hoses are manufactured with a greater wall thickness but are similarly hampered by increased manufacturing costs while also being much heavier and more difficult to use.
Accordingly, it would be desirable to provide a lightweight, easy to manipulate, burst-resistant hose without making adaptations along the full end-to-end length of the hose.
In an aspect of the invention, there is provided a reinforced hose comprising: a hollow hose tubing having first and second open ends; a ferrule installed on the hose tubing about the first open end; a pressure sleeve concentrically installed over an outer surface of the hose tubing, the pressure sleeve having first and second terminal ends with a hollow cylindrical tube formed therebetween, wherein: an inner diameter of the pressure sleeve is larger than an outer diameter of the hose tubing; the first terminal end of the pressure sleeve is longitudinally aligned with the first open end of the hose tubing; and the second terminal end of the pressure sleeve extends longitudinally beyond a proximal end of the ferrule such that the longitudinal length of the pressure sleeve is greater than that of the ferrule, the proximal end of the ferrule being the portion thereof farthest from the first open end of the hose tubing; and a first interference joint coupling the outer surface of the hose tubing to an inner surface of the pressure sleeve, the first interference joint comprising a contact patch located between the second terminal end of the pressure sleeve and the proximal end of the ferrule.
In a further aspect, the inner surface of the pressure sleeve is in contact with the outer surface of the hose tubing along the full longitudinal length of the pressure sleeve; and a portion of the pressure sleeve, located between the proximal end of the ferrule and the first open end of the hose tubing, is compressed between the outer surface of the hose tubing and an inner surface of the ferrule.
In a further aspect, the ferrule is crimped in place on top of concentric layers formed by the pressure sleeve and the hose tubing, such that the portion of the pressure sleeve is compressed.
In a further aspect, the reinforced hose further comprises a second interference joint coupling the outer surface of the hose tubing to the inner surface of the pressure sleeve, the second interference joint located between the proximal end of the ferrule and the first open end of the hose tubing.
In a further aspect, one or more of the first interference joint and the second interference joint comprises a contact patch formed by heat shrinking the pressure sleeve onto the outer surface of the hose tubing.
In a further aspect, the first and second interference joint comprise a single contact patch formed by a single heat shrinking operation.
In a further aspect, the ferrule is crimped in place about the first open end of the hose tubing; and the ferrule is encapsulated along its full longitudinal length by the pressure sleeve.
In a further aspect, the outer surface of the hose tubing is in direct contact with an inner surface of the ferrule.
In a further aspect, the pressure sleeve is installed on top of the crimped ferrule such that the outer surface of the ferrule is in contact with the inner surface of the pressure sleeve along a second contact patch.
In a further aspect, the second contact patch between the outer surface of the ferrule and the inner surface of the pressure sleeve: has a longitudinal length substantially equal to that of the ferrule; and is located between the proximal end of the ferrule and the first open end of the hose tubing.
In a further aspect, the second contact patch comprises a second interference joint.
In a further aspect, the second interference joint comprises a heat shrink joint that radially compresses the ferrule and hose tubing along the second contact patch.
In a further aspect, the first interference joint comprises a heat shrink joint along the first contact patch.
In a further aspect, the first and second interference joints are formed in a single, continuous heat shrink operation.
In a further aspect, the reinforced hose further comprises: a second ferrule installed about the hose tubing at the second open end; a second pressure sleeve concentrically installed over an outer surface of the hose tubing, the second pressure sleeve having first and second terminal ends with a hollow cylindrical tube formed therebetween, wherein: an inner diameter of the second pressure sleeve is larger than an outer diameter of the hose tubing; the first terminal end of the second pressure sleeve is longitudinally aligned with the second open end of the hose tubing; and the second terminal end of the second pressure sleeve extends longitudinally beyond a proximal end of the second ferrule, such that the longitudinal length of the second pressure sleeve is greater than that of the second ferrule, the proximal end of the second ferrule being the portion thereof farthest from the second open end of the hose tubing; and a third interference joint coupling the outer surface of the hose tubing to an inner surface of the second pressure sleeve, the third interference joint comprising a contact patch located between the second terminal end of the second pressure sleeve and the proximal end of the second ferrule.
In a further aspect, the concentric arrangement of layers comprising the hose tubing at the second open end, the second ferrule, and the second pressure sleeve is installed in the same order as the concentric arrangement of layers comprising the hose tubing at the first open end, the first ferrule, and the first pressure sleeve.
In a further aspect, the concentric arrangement of layers comprising the hose tubing at the second open end, the second ferrule, and the second pressure sleeve is installed in a different order as compared to the concentric arrangement of layers comprising the hose tubing at the first open end, the first ferrule, and the first pressure sleeve.
In a further aspect, the hollow cylindrical tube formed between the first and second terminal ends of the pressure sleeve comprises a continuous smooth surface having a constant inner diameter.
In a further aspect, the pressure sleeve has a constant inner diameter prior to installation over the crimped ferrule.
In a further aspect, the hose tubing comprises one or more of polyvinyl chloride (PVC), thermoplastic elastomer (TPE), thermoplastic polyurethane (TPU), nylon, polyethylene, and synthetic and natural rubber.
In order to describe the manner in which the above-recited and other advantages and features of the disclosure can be obtained, a more particular description of the principles briefly described above will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. Understanding that these drawings depict only exemplary embodiments of the disclosure and are not therefore to be considered to be limiting of its scope, the principles herein are described and explained with additional specificity and detail through the use of the accompanying drawings in which:
Various embodiments of the disclosure are discussed in detail below. While specific implementations are discussed, it should be understood that this is done for illustration purposes only. A person skilled in the relevant art will recognize that other components and configurations may be used without parting from the spirit and scope of the disclosure. Additional features and advantages of the disclosure will be set forth in the description which follows, and in part will be obvious from the description, or can be learned by practice of the herein disclosed principles.
It will be appreciated that for simplicity and clarity of illustration, where appropriate, reference numerals have been repeated among the different figures to indicate corresponding or analogous elements. In addition, numerous specific details are set forth in order to provide a thorough understanding of the embodiments described herein. However, it will be understood by those of ordinary skill in the art that the embodiments described herein can be practiced without these specific details. In other instances, methods, procedures and components have not been described in detail so as not to obscure the related relevant feature being described. The drawings are not necessarily to scale, and the proportions of certain parts may be exaggerated to better illustrate details and features. The description is not to be considered as limiting the scope of the embodiments described herein.
Hoses are often used in a manner in which they are repeatedly pressurized (i.e., used to convey a pressurized fluid such as water from a spigot) for short bursts of time. For example, in a common scenario a garden hose might be turned on and off 5-10 times per day by a homeowner watering plants that are spread about various different locations. Pressure cycling alone can ultimately cause failures in hoses due to the shear forces and expansion experienced in the hose wall during each cycle. Exacerbating this effect is the fact that garden hoses are used over wide ranges of fluid pressure and temperature.
The most common failure mode for many garden hoses is bursting, typically at the portion of the hose wall where the shearing forces are at a maximum during pressurization. In particular, garden hoses are prone to bursting at the ferrule or other coupling attachment point, where the end hardware of the hose is crimped into or otherwise attached to the hose wall. For example,
For example, when subjected to an impulse test in which water at a fixed temperature is cycled between an upper and lower pressure threshold (e.g., from 0-100 PSI (pounds per square inch)), hoses such as the two hoses 110, 120 were observed experiencing burst failures directly behind the ferrule after only a few hundred pressurization cycles of the pressure impulse test with a water temperature of 120° F. By contrast, reinforced garden hoses according to aspects of the present disclosure were observed withstanding over 1,000 pressurization cycles of the same pressure impulse test (at the same 120° F. water temperature) without failure, before the impulse test was ended—still without the reinforced hoses experiencing a bursting or other failure.
In another example, a PLC was used to control and run a pressure impulse test for 120 hours or 43,000 pressurization cycles. Cold water, at a temperature of 70° F. was cycled between 0-100 PSI at six pressure cycles per minute. Conventional, un-reinforced hoses such as the two hoses 110, 120 seen in
Disclosed is hose having a reinforced pressure sleeve (also referred to herein as a “burst sleeve”) provided at one or more of its open ends, such that the reinforced hose exhibits greater durability and handling characteristics and moreover is resistant to bursting and kinking. In some embodiments, the presently disclosed hose having a reinforced pressure sleeve provides at least a 10-15% improvement in life cycle durability when compared to conventional, non-pressure sleeve-reinforced hoses. Additionally, in some embodiments a greater than 15% improvement in life cycle durability can be achieved when stronger and/or thicker materials are chosen for the pressure sleeve, as will be discussed in greater detail below. In some embodiments, the reinforced pressure sleeve can be installed underneath the ferrule at a hose end and/or can be installed on top of the ferrule at the hose end. It is appreciated that although a ferrule is referenced in the following discussion and is depicted in the instant figures, that this is for purposes of example and is not to be construed as limiting—other end coupling hardware and assemblies for garden hoses can be reinforced with pressure sleeves in either the over or under configuration, all without departing from the scope of the present disclosure.
Reinforced hose 210 is an example of the pressure sleeve over ferrule configuration, in which pressure sleeve 216 is installed such that it encapsulates the ferrule at the open end of the hose (i.e., the end hardware of the hose typically having male or female threading allowing the hose to be connected to spigots, nozzles, etc.). Pressure sleeve 216 may encapsulate the ferrule fully, as is illustrated, or may encapsulate the ferrule only partially. In addition to the ferrule, pressure sleeve 216 also encapsulates a portion of the outer surface of the hose tubing that is immediately below the proximal end of the ferrule (i.e., the far end of the ferrule, away from the open end of the hose through which fluid enters/exits). In some embodiments, it is contemplated that pressure sleeve 216 is affixed or otherwise coupled to hose 210 without the use of adhesives and/or mechanical fasteners. For example, the pressure sleeve can comprise a heat shrink material such as polyolefin, such that the pressure sleeve is installed onto the reinforced hose and then coupled or otherwise affixed via the application of heat, although it is appreciated that various other heat shrink materials can be utilized without departing from the scope of the present disclosure.
In some embodiments, pressure sleeve 216 can be installed onto hose 210 during manufacture, i.e., after the manufacture of the hose tubing itself but prior to the attachment of a ferrule or end coupling to the open end of the hose. For example, pressure sleeve 216 can be slid down the length of the hose tubing (toward the opposite open end) to allow a ferrule to be crimped onto the closer open end. With the ferrule in place, pressure sleeve 216 can then be moved back towards the closer open end and longitudinally aligned with the crimped ferrule. With suitable alignment achieved, a heat shrink operation can be applied to shrink pressure sleeve 216 to encapsulate the crimped ferrule and reinforce the transition zone between the wall of the hose tubing and the bottom end of the ferrule. In some embodiments, a complete end coupling assembly (e.g., threaded for male or female attachment to spigots, nozzles, etc.) can be fit in place to the ferrule prior to heat shrinking pressure sleeve 216 in place. As will be discussed in greater depth below with respect to
Returning to the discussion of reinforced hose 210 having a pressure sleeve over ferrule configuration, regardless of the longitudinal extent to which pressure sleeve 216 reaches toward the terminal end of reinforced hose 210, pressure sleeve 216 is sized and installed such that it will cover the transition zone between the outer tubing of the hose and the lower lip/circumference of the ferrule installed on the hose. For reference, this transition zone is indicated at 231 on the non-reinforced hose 230—recall from
Having briefly discussed the pressure sleeve over ferrule configuration of reinforced hose 210, the disclosure turns now to the pressure sleeve under ferrule configuration—an example of which is illustrated by reinforced hose 220. In particular, a pressure sleeve 226 is installed such that the pressure sleeve's full length makes contact with the outer surface of hose 220 but—unlike in the pressure sleeve over ferrule configuration—does not encapsulate or otherwise make contact with the outer surface of the ferrule at the open end of hose 220. Instead, the ferrule encapsulates the upper portion of pressure sleeve 226, in the pressure sleeve under ferrule configuration of reinforced hose 220.
In some embodiments, pressure sleeve 226 can be fitted on the tubing of hose 220 in a first step, and a ferrule or other end connector hardware can be subsequently installed on top of both the pressure sleeve and the hose tubing in a second step (e.g. by crimping the ferrule to radially compress the hose wall and pressure sleeve between the inner and outermost ferrule portions). In instances where pressure sleeve 226 comprises a heat shrink material, a heat shrinking operation can be applied as an intermediate step before crimping on the ferrule. For example, after pressure sleeve 226 has been situated about the outer surface of the hose tubing near its open end, the pressure sleeve can be shrunk onto the hose tubing via a hot water bath/dip or other application method causing sufficient heat transfer into pressure sleeve 226 to trigger shrinking. In some embodiments, the heat shrinking operation can be applied or performed after the ferrule has been crimped in place on top of pressure sleeve 226 (although such a scenario might require that the pressure sleeve OD, in a non-shrunken state, closely match the ID of the ferrule—otherwise, as pressure sleeve 226 contracts from the heat shrinking operation, its outer surface will pull away from the crimped attachment with the ferrule).
Other heat shrinking methods such as the use of a heat gun or radiant heat may also be employed, although these methods risk overheating the actual hose material itself and causing undesirable warping, weakening or other damage. Depending on the size differential, and in particular the diameter differential, between the hose tubing, the pressure sleeve and the ferrule, in some embodiments the ferrule can be crimped onto a first end of pressure sleeve 226 and the tubing of hose 220 subsequently or simultaneously inserted into the second end of the pressure sleeve.
As illustrated, the pressure sleeve extends beyond the proximal end of the ferrule (i.e., towards the midpoint of the hose's length) in both reinforced hose 210 and reinforced hose 220. By extending beyond the ferrule, pressure sleeves 216, 226 can provide the additional benefit of strain relief, and in some embodiments the total length of the pressure sleeve can be increased or decreased in order to impart a greater or lesser degree of strain relief functionality to the reinforced hose. Additionally, a more rigid pressure sleeve, whether by way of increased wall thickness or material choice, can in some embodiments also be utilized to provide additional strain relief to the reinforced hoses 210, 220. In some embodiments, both reinforced hoses 210, 220 can be configured with pressure sleeves that are substantially similar or identical.
Advantageously, the use of the presently disclosed pressure sleeves, whether in the over or under ferrule configuration, specifically targets and reinforces the area in which conventional or non-reinforced hoses are most prone to suffering burst failures, i.e., the transition zone 231 between hose wall and ferrule. Unlike other reinforcement techniques such as adding additional hose/tubing layers, additional reinforcement yarns, using thicker hose/tubing walls or reinforcement yarns, the disclosed pressure sleeves do not require integration along the full length of the hose. The aforementioned reinforcement techniques are achieved by making modifications to the input components to the continuous process in which the hose or tubing is manufactured—such reinforcements therefore must be applied to the entire length of the hose, even when it is only the transition zones 231 near the ferrules that are in need of reinforcement against bursting. Extraneous reinforcement running the whole length of the hose increases weight and can negatively impact handling characteristics, making the hose more difficult to lift or, in the case of a more rigid hose, more difficult to maneuver and manipulate. Moreover, full-length hose reinforcement techniques come at an increased cost to both the manufacturer and the consumer.
By applying selective reinforcement to just the most sensitive, burst-prone zones, the reinforced hoses 210, 220 of the present disclosure eliminate the inefficiencies and inconveniences associated with full-length hose reinforcement as discussed above. Moreover, when pressure sleeves are installed at one or both ferrules/open ends of a hose, the hose tubing itself can be built thinner while still maintaining or exceeding the performance achieved by the (non-pressure sleeve reinforced) tubing at its original thickness. A thinner hose/tubing wall not only reduces manufacturing costs but can also reduce shipping costs due to its corresponding lower weight. To end users, a thinner hose wall results in better handling characteristics, i.e., because the thinner hose can be both lighter and more flexible, while the use of pressure sleeves to reinforce the thinner hose tubing provides burst protection and greater durability specifically targeted to the region of hose wall near the ferrules that is the source of most failures and user complaints. Further still, the strain relief functionality imparted by the pressure sleeves can be useful with thinner hose walls, which might otherwise be more prone to kinking in the absence of the pressure sleeves/strain relief.
The disclosure turns now to
As illustrated, pressure sleeve 320 has an inner diameter (ID) that is larger than the outer diameter (OD) of hose tubing 310; in other words, pressure sleeve 320 is sized such that it can encompass hose tubing 310 within its interior volume. This allows pressure sleeve 320 to fit over hose tubing 310 during the installation or manufacturing process. Moreover, the ID of pressure sleeve 320 can be sized such that it accounts for the OD of hose tubing 310 and any tolerance variation in this OD. For example, if hose tubing 310 is manufactured with an OD tolerance of ±0.05 inches, then the ID of pressure sleeve 320 in its non-shrunken state will be greater than the hose tubing OD+0.05 inches. In such a scenario where the pressure sleeve ID is only slightly larger than the hose tubing OD, pressure sleeve 320 will be tight-fitting when installed on hose tubing 310, even prior to the application of a heat shrink process. A lubricant can be utilized to reduce friction and resistance when installing a tight-fitting pressure sleeve onto a hose tubing.
Rather than using a tight-fitting pressure sleeve and lubricants, in some embodiments pressure sleeve 320 can be sized to have an ID that is appreciably larger than the OD of hose tubing 310 (e.g., at least 10-25% larger than the hose tubing OD). In this manner, pressure sleeve 320 can be easily installed onto hose tubing 310 without requiring the application of force to overcome the frictional resistance that arises with a tight-fitting pressure sleeve. Additionally, a “loose” pressure sleeve can be manually installed onto a hose tubing or integrated with an automated manufacturing process for such tubings (e.g., pressure sleeves could be installed onto sections of hose tubing as they come out of an extruder, with the pressure sleeves either pre-cut or cut in real-time during installation). Moreover, the use of a “loose” fitting pressure sleeve 320 can permit a single/uniform size strategy to be employed in manufacturing reinforced hoses having different ODs—a pressure sleeve that is sized to fit around the largest OD hose tubing can be installed and shrunk onto various other hose tubings having smaller ODs, given the wide range of shrink percentage exhibited by pressure sleeve 320, and advantageously reduces manufacturing costs and complexity by significantly reducing the total number of pressure sleeve sizes that need to be maintained in inventory.
As indicated by the directional arrows between the components depicted in
In some embodiments, one or more pressure sleeves 320 can be placed about hose tubing 320 and then allowed to move or float freely along the longitudinal length of the hose tubing (e.g., because the ID of the pressure sleeves is sufficiently larger than the OD of the hose tubing). Such a configuration might be utilized when wishing to install the pressure sleeve(s) during the manufacture of hose tubing 310 (i.e., through an in-line step, e.g., as the hose tubing comes out of an extruder) without having to reduce the speed of hose tubing manufacture to match the process speed of aligning and heat shrinking a pressure sleeve 320 onto one or both ends of the hose tubing. In this manner, the pressure sleeve(s) 320 can be allowed to float along the length of hose tubing 310 until a separate alignment and heat shrinking process is performed at a subsequent time. This process can be performed manually or can be automated.
Pressure sleeve 320 is first brought into alignment with the open end of hose tubing 310 onto which it will be shrunk (if two pressure sleeves are installed, then each pressure sleeve is brought into alignment with its respective open end of hose tubing 310). For under the ferrule configurations such as the one depicted in
After pressure sleeve 320 and hose tubing 310 are brought into the desired alignment, a heat shrink process is applied to bring the inner surface of pressure sleeve 320 into tight contact with the outer surface of hose tubing 310, eliminating any gap between the pressure sleeve ID and hose tubing OD that was previously present, e.g., due to a “loose” fitting un-shrunken pressure sleeve. As mentioned previously, the pressure sleeve can be shrunk onto the hose tubing via a hot water bath or dip. Other heat application methods causing sufficient heat transfer into pressure sleeve 320 to trigger shrinking can also be utilized without departing from the scope of the present disclosure. In some embodiments, the heat shrinking operation can be applied or performed after the ferrule has been crimped in place on top of pressure sleeve 226 (although such a scenario might require that the pressure sleeve OD, in a non-shrunken state, closely match the ID of the ferrule—otherwise, as pressure sleeve 226 contracts from the heat shrinking operation, its outer surface will pull away from the crimped attachment with the ferrule).
Other heat shrinking methods such as the use of a heat gun or the application of radiant heat may also be employed. In some scenarios, these indirect heat transfer methods (“indirect” when considered in comparison to the “direct” method of submerging the pressure sleeve into a hot water or other fluid bath) can be utilized on the same manufacturing line as the hose tubing itself, although these methods risk overheating the actual hose tubing material itself and causing undesirable warping, weakening or other damage.
In the example of
The disclosure turns next to
As illustrated in
With ferrule 430 and/or fitting 440 in place on the open end of hose tubing 410, pressure sleeve 420 can then be moved towards the same open end of hose tubing 410, up and over the outer surface of ferrule 430—into the aligned position for installation of pressure sleeve 420 via a heat shrink process. This step is shown in
In some embodiments, the installation of fitting 440 can provide an alignment mechanism that brings the open ends of pressure sleeve 420 and hose tubing 410 into the desired relative position for heat shrinking. As seen in
In both the sleeve under ferrule and sleeve over ferrule configurations (depicted in
In the sleeve under ferrule configuration of
In the sleeve over ferrule configuration of
The duration of the hot water bath or heat-shrinking process (applied to either the sleeve over ferrule configuration or the sleeve under ferrule configuration) depends on factors that include the temperature of the process, heat transfer coefficients, thickness of the pressure sleeve, material composition of the pressure sleeve, etc. As mentioned previously, the temperature of the heat-shrinking process may, in some embodiments, be reduced to ensure that the hose tubing or other components besides the pressure sleeve do not experience undesired thermal contraction, melting, etc.
If the flanged portion of fitting 440 is not wider than the OD of the non-shrunken pressure sleeve 420, this flanged portion may still provide either a visual guide/reference point for manual alignment of the open ends of the pressure sleeve and the hose tubing, or can achieve the same functionality described above if the flanged portion of fitting 440 is wider than the ID of the non-shrunken pressure sleeve 420.
Once pressure sleeve 420 has been shrunken over the ferrule 440 in the desired alignment position, the shrunken pressure sleeve provides a compressive force in the radial direction that reinforces the hose tubing against shear forces that otherwise typically cause burst failures in unreinforced hoses at the transition point between the ferrule and the hose tubing wall.
