Patent Application
20190257397
The present disclosure relates generally to coupling assemblies that couple two or more loads together in tension. More specifically, the present disclosure relates to a coupling assembly that includes a drive assembly that drives an axial movement of a shaft with rotational movements of gears, and a bearing arrangement that minimizes a transmission of rotational and axial movements to housings of the coupling assembly.
Coupling assemblies are often used to join lines, such as cables, attached to heavy loads. Gear arrangements of such coupling assemblies are often used to facilitate the use of a less powerful input force or prime mover to perform tasks on the heavy loads. The gear arrangements may also reduce output speed based on the input of a prime mover having an undesirably high output speed. Example implementations of coupling assemblies provided with a gear arrangement that facilitate the performance of tasks on heavy loads include turnbuckles or load binders. For example, a turnbuckle may be used to adjust a tension between, and/or a total length of, lines attached to heavy loads using a hand-operated tool, such as a wrench, or a motor operated tool, such as a power driver.
Coupling assemblies as discussed herein may be used when transporting solid and/or liquid cargo via barges along bodies of water. The use of barges to transport cargo has become increasingly attractive due to an increase in a desire to transport cargo more efficiently and with less undesirable emissions. Recent studies indicate that transport of cargo by barge is more than 25% more efficient than transport by rail and more than three times as efficient as transport by truck. In addition, transport of cargo by barge results in significantly less undesirable emissions than transport by rail and truck.
In order to increase the efficiency of transport of cargo via barges, a number of barges may be grouped together in a barge “train” or “tow” by cables and pushed or pulled by a single or several boats. For example, as many forty barges may be held together in a group of five rows by eight rows. In such barge “trains” or “tows,” it may be desirable to adjust the tension and/or length of the cables holding the barges together to facilitate control of the barges during the release or addition of barges from the group, or during navigation of a waterway. Coupling assemblies, such as turnbuckles or load binders, are often used for facilitating such adjustments.
However, especially in the case of a power driver, it is often the case that a tool used to operate such a coupling assembly will have a tendency to become misplaced and disengaged from the coupling assembly due to forces generated by movements of components of a respective gear arrangement within the coupling assembly. In particular, such movements may generate forces that are transmitted to the housing or casing of the coupling assembly and cause the entire assembly to move away from the tool being used to adjust the coupling assembly. Thus, continued adjustment of the coupling assembly may require an operator to perform a physically-demanding task of attempting to hold the coupling assembly in place so a tool remains engaged with the coupling assembly. Moreover, the design of such turnbuckles can be cumbersome as they may comprise a lever arm or handle bar that provides a gripping location for the operator to prevent the coupling assembly from rotating or twisting during use.
These and other issues are solved by a coupling assembly and method of coupling loads with the coupling assembly, of the present disclosure.
According to certain aspects of the present disclosure, a coupling assembly may include a first shaft, a first housing including a first housing body that defines a first housing cavity that may be configured to receive the first shaft, and a second housing including a second housing body that may define a second housing bore, the second housing may be configured to attach to the first housing. According to another aspect of the present disclosure, the coupling assembly may include a first gear that is positioned in the second housing bore and may be configured to engage the first shaft proximate to the first housing cavity, a first bearing positioned between the first gear and the second housing body within the second housing bore, a third housing including a third housing body that may define a main cavity and at least one peripheral cavity, a second gear that is positioned in the main cavity and may be configured to engage the first gear, and a second shaft extending through the main cavity and the at least one peripheral cavity, the second shaft may be configured to engage the second gear. According to another aspect of the present disclosure, the coupling assembly may include a second bearing positioned between the second shaft and a wall of the third housing body that may define one of the main cavity and the at least one peripheral cavity. According to a further aspect of the present disclosure, the second shaft may rotate relative to the third housing and cause the first gear to drive the first shaft in an axial movement relative to the first housing and the second housing.
According to certain aspects of the present disclosure, a method of coupling two loads includes providing a coupling assembly, attaching a first housing of the coupling assembly to one of the two loads, attaching a first shaft of the coupling assembly to the other of the two loads, and operating a drive assembly of the coupling assembly to adjust a tension between the two loads. According to another aspect of the present disclosure, providing the coupling assembly may include providing a second housing attached to the first housing, a first gear positioned in the second housing, a threaded engagement between the first shaft and the first gear, a first bearing that is positioned between the first gear and an inner circumferential wall of the second housing and may be configured to support a rotation of the first gear relative to the second housing, a third housing attached to the second housing, a second gear that is positioned in the third housing and may be engaged with the first gear through a gear slot defined by the second housing, and at least one bearing positioned between a second shaft of the drive assembly and a recessed wall of the second housing. According to another aspect of the present disclosure, operating the drive assembly may include rotating the second shaft of the drive assembly.
According to cert aspects of the present disclosure, a coupling assembly may include a first shaft including a threaded external surface and a threaded internal surface, a plug including a plug head and a threaded body engaged with the threaded internal surface, a first housing including a first housing body that defines a first housing cavity configured to receive the first shaft, a second housing including a second housing body that defines a second housing bore, a first gear positioned in the second housing bore and engaged with the threaded external surface, and a first bearing positioned between the first gear and the second housing body within the second housing bore. According to another aspect of the present disclosure, the coupling assembly may include a third housing including a third housing body that defines a main cavity and a peripheral cavity on opposite sides of the main cavity, a second gear positioned in the main cavity and engaged with the first gear, a second shaft extending through the main cavity and each peripheral cavity and being engaged with the second gear, and a pair of bearings positioned in the third housing, each of the pair of bearings may be positioned in a respective peripheral cavity between the second shaft and third housing body. According to another aspect of the present disclosure, the second shaft may rotate relative to the third housing and cause the first gear to drive the first shaft in an axial movement relative to the first housing and the second housing. According to a further aspect of the present disclosure, the plug may be configured to slide relative to the first housing, and a rim of the plug head may engage an inner circumferential wall of the first housing and have a diameter greater than an outer diameter of the external threaded surface of the first shaft.
Aspects of the disclosure will now be described in detail with reference to the figures, wherein like reference numbers refer to like elements throughout, unless specified otherwise. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. For the purposes of this disclosure and unless otherwise specified, “a” or “an” means “one or more”. Still further, using “and” or “or” in the detailed description is intended to include “and/or” unless specifically indicated otherwise.
Aspects of the present disclosure described herein are directed toward a coupling assembly that may include a first shaft, a first housing including a first housing body that defines a first housing cavity that may receive the first shaft, a second housing including a second housing body that may define a second housing bore, a first gear that is positioned in the second housing bore and may engage the first shaft, and a first bearing positioned between the first gear and the second housing body within the second housing bore. The coupling assembly may include a drive assembly provided with a third housing, a second shaft that extends through a main cavity and peripheral cavities defined by a third housing body, and a second gear that may be positioned in the main cavity and configured to engage the first gear through a gear slot defined by the second housing body. The drive assembly may further include at least one bearing, or a plurality of bearings according to an aspect of the present disclosure, that supports rotational movement and/or limits an axial displacement of the second shaft and the second gear. Rotation of the first gear by the second gear, which may be driven by a tool rotating the second shaft, rotates a threaded engagement between the first gear and the first shaft such that a threaded inner surface of the first gear axially displaces a thread outer surface of the first shaft, and drives an axial movement of the first shaft.
The plurality of bearings in the third housing can optimize a transmission of a driving force that rotates the first gear, and at the same time prevents the movements of the second shaft and the second gear from being transmitted to the first, second, and third housings. The first bearing provided in the second housing supports the rotation of the first gear and serves as a buffer between an inner circumferential wall of the second housing and outer most surfaces of the first gear and the first shaft. Accordingly, the rotational movement of the first gear, and the axial movement of the first shaft, are not transmitted to the second housing or the first housing which is attached to the first housing.
The arrangement of bearings in the coupling assembly may isolate the first and second housings from the movements of the first gear, the second gear, and the first shaft. As a result, the coupling assembly will not be subject to vibrations or other movements of its internal components that may complicate keeping the coupling assembly in a position to remain engaged with a tool, in particular a power driver, and be continuously operated. More generally, the coupling assembly according to the present disclosure will not move away from the tool to the point of disengagement as a result of the movements of the components of the coupling assembly. As such, no lever arm or handle bar is needed for gripping by an operator to prevent the coupling assembly from rotating or twisting during use. Thus, the coupling assembly can be less cumbersome, weigh less, and less likely to snag on obstacles than coupling assemblies that require a lever arm or handle bar to prevent twisting.
As assembled, the housing end-face 206 may engage (e.g. abut) one side of a first washer 214 of the coupling assembly 100. An opposite side of the first washer 214 may be configured to engage an end-face 221 of a first gear body 220 of the first gear 110. The first gear body 220 may define a first cylindrical portion 222 that is disposed between a first lip 223 and a second lip 225, which may also be defined by the first gear body 220. A first gearing component 224 may be provided on (e.g. formed with, attached to) the first cylindrical portion 222 between the first lip 223 and the second lip 225.
Gearing components as defined herein may include a structural component of one gear configured to mesh with and drive or be driven by a structural component of another gear. Accordingly, a gearing component may include a plurality of teeth (helix tooth, spur tooth, bevel tooth, etc.), cogs, or a helical spiral (e.g. threads, a worm). According to an aspect of the present disclosure, the first gearing component gearing 224 may include teeth such as cylindrical or enveloping teeth, and thereby define a worm gear of a worm drive. According to an aspect of the present disclosure, the diameter of each of the first and second lips 223, 225 may be equal to or greater than a diameter of an addendum circle or outer diameter defined by the first gearing component 224.
The first gear body 220 further defines a second cylindrical portion 226 that may have an outer diameter less than that of the first cylindrical portion 222, and extend along a longitudinal axis of the first gear 110 from the second lip 225 to the exposed end 111. A first gear bore 227 of the first gear 110 is defined by a first threaded inner surface 228 of the first gear body 220, and extends from the end-face 221 to the exposed end 111. The second cylindrical portion 226 may be configured to receive or have fitted thereon a first bearing 230, and the first threaded inner surface 228 may be configured to engage the first shaft 102 as discussed in more detail herein.
As illustrated, the coupling assembly 100 further includes a second washer 232 that may engage and maintain (aid in maintaining) the first bearing 230 in a respective functional position between the second lip 225 and a wall (see
In an assembled state of the coupling assembly 100, the first housing 106, the spacer 210, and the second housing 108 are orientated relatively so that the first attachment bores 208, the spacer bores 212, and the second attachment bores 240 are aligned so that each combination of bores may receive one or more first set screws 242. As a result, the second housing 108 may be attached to the first housing 106 with the spacer 210 positioned between an outer surface of the first housing 106 and an inner surface of the second housing 108 (see
The coupling assembly 100 includes a plug 244 having a plug head 246 and a threaded body 248. The threaded body 248 is configured to engaged (i.e. be threaded to) a second threaded inner surface 252 defined by a first shaft body 250 of the first shaft 102. The first shaft body 250, further defining a threaded external surface 254, extends from shaft arms 256 that have eyeholes 258 formed therein to receive a respective screw or bolt 118. The second threaded inner surface 252, and a portion of an inner surface of the first shaft body 250 not including second threaded inner surface 252, define a first shaft cavity 259.
The main cavity 262 is configured to receive a second gear 270 between second bearings 276 that are also configured to be positioned in the main cavity 262. The second gear 270 includes a second gearing component 272 configured to engage (i.e. mesh) with the first gearing component 224 of the first gear 110. According to an aspect of the present disclosure, the second gearing component 272 may be defined by a body of the second gear 270 in a configuration of a worm (e.g. cylindrical or enveloping worm), such that the first gear 110 and the second gear 270 define a worm drive. According to another aspect of the present disclosure, the first and second gears 110, 270 may be screw gears. The body of the second gear 270 may further define a second gear bore 276 that is configured to receive the second shaft 116. The second shaft 116 may be supported for rotation within the third housing 114 by a pair of third bearings 280, each third bearing 280 being positioned in a respective peripheral cavity 264.
As illustrated in
According to an aspect of the present disclosure, various components of the coupling assembly 100 may be formed from materials that are resistant to corrosion (e.g., stainless steel). For example, sub-components or the entirety of one or more of the first shaft 102, the second shaft 116, the first housing 106, the second housing 108, the third housing 114, the first gear 220, and the second gear 270 may be formed of stainless steel. According to an aspect of the present invention, incorporation of steel components in the coupling assembly 100 may provide improved resistance to corrosion as compared to other coupling assemblies known in the art. As such, the coupling assembly 100 of the present disclosure may withstand repeated use in various weather conditions with little or no change to its respective functionality, as compared to the reduced capabilities of other coupling assemblies known in the art given the same use.
According to another aspect of the present disclosure, one advantage of the construction of the coupling assembly 100 is that various components can be disassembled, and sub-components, such as the first and second washers 214, 232 and the first gear 110 relative to the second housing 108, may be easily replaced. For example, in a situation where portions of the threaded external surface 254 of the first shaft 102 have become overly worn or even stripped, the first set screws 242 may be removed and the second housing 108 detached from the first housing 106. The second housing 108 may continue to be engaged with the first shaft 102, with the plug 244 exposed and freely removable. Accordingly, the plug 244 may be rotated and detached from the first shaft 102. According to an aspect of the present invention, the second shaft 116 may then be held in place so the first gear 110 does not rotate with the first shaft 102 that is rotated and threaded out of the second housing 102 to thereby be replaced.
An operation of the coupling assembly 100 according to the present disclosure, will be described with reference to
In more specific terms, a tool such as a driver or a wrench, may engage a shaped recess 302 (e.g. socket) defined by/formed within the drive head 290. The engagement with the shaped recess 302 causes a rotational movement of the tool about a drive axis 300 of the drive assembly 112 to be transferred to the second shaft 116. A stepped portion 304 of the second shaft 116 is disposed between the collar 292 and the drive shaft 294, and defines a bearing surface of the second shaft 116. More specifically, the stepped portion 304 may rotate relative to components of one of the third bearings 280. The stepped portion 304 together with the retention ring 124, which is received in a shaft groove 306 formed adjacent to the distal end 122 of the second shaft 116, locate and at least in part maintain an axial position of the drive shaft 294 with respect to the third housing 114 during rotation.
The shaft slot 296 defined by the drive shaft 294 is configured to receive a key 310 defined by a body of the second gear 270. The key 310 protrudes within the second gear bore 274 to extend along the drive axis 300; the drive shaft 294 and the second gear 270 being coaxial with the drive axis 300. It will be understood by those having ordinary skill in the art that a key may be formed to extend from the drive shaft 294 and engage in a slot defined in an inner surface of the second gear 270. In either of the configurations discussed herein, during the operation of the coupling assembly 110, the rotation of the second shaft 116 will be transmitted to the second gear 270 via an engagement between the key 310 and the shaft slot 296 such that the second gear 270 rotates about the drive axis 300.
The second bearings 276 maintain an axial position of the second gear 270 within the main cavity 262 relative to the third housing 114 during the operation of the coupling assembly 100. More specifically, each second bearing 276 is positioned between, and may engage, a respective end of the second gear 270, and a first combined wall defined by: (1) a first side wall 330 of the third housing 114; (2) an end of a respective third bearing 280; and (3) a second side wall 340 of the second housing 108. The first side wall 330 is defined by/formed within the third housing body 260, and defines in part the main cavity 262. The second side wall 340 is defined by/formed within the second housing body 234, and defines the gear slot 238 within the second housing 108.
According to an aspect of the present disclosure, the second bearings 276 may be thrust bearings (e.g. thrust ball bearings, spherical roller thrust bearings, fluid bearings, etc.) and serve as axial buffers along the drive axis 300 between the second gear 270 and the first and second side walls 330, 340. Thus, the second bearings 276 may absorb and minimize a transmission of axial movement of the second gear 270 and the second shaft 116 to the second and third housings 108, 114 during the operation of the coupling assembly 100. In addition, the second bearings 276 may be coated with a friction reducing coating, formed of a material for which a coefficient of friction therewith is small, and/or be embedded with a lubricant (e.g. oil). Accordingly, the second gear 270 may rotate relative to components of the second bearings 276, while at the same time, components of the second bearings 276 may rotate relative to a respective first combined wall. As a result, a minimal amount of the rotational movement of the second gear 270 is transmitted to the second and third housings 108, 114.
Upon the transfer of the rotational movement of a tool via the shaped recess 302, the third bearings 280 support, and more importantly facilitate, the combined rotation of the drive shaft 294 (second shaft 116) and the second gear 270 relative to the third housing 114 and the second housing 108. According to an aspect of the present disclosure, the third bearings 280 may be roller bearings (e.g. needle roller, cylindrical roller, spherical roller, etc.). Each third bearing 280 may include an outer surface (e.g. an outer surface of an outer race) that is received in and engages a respective annular wall 332 of the third housing 114, and a respective recessed wall 342 of the second housing 108. As illustrated in
The bearing arrangement limits any axial movement of the second shaft 116 and second gear 270 from the second and third housings 108, 114. In addition, the bearing arrangement optimizes an efficiency (i.e. reduces resistance to an optimal degree) of the rotational movement of the second gear 270 to drive a rotation of the first gear 110 during the operation of the coupling assembly 100.
The rotation about the drive axis 300 by the second gear 270 drives a rotation of the first gear 110 about the translational axis 350, which is transverse to the drive axis 300. As discussed above, the first gear 110 may provide a worm gear, and the second gear 270 may provide a worm, of a worm drive. Accordingly, a speed ratio between the second gear 270 and the first gear 110 may be such that the first gear 110 constitutes a speed reducing gear. For example, a single revolution of the second gear 270 may cause the second gearing component 276 (worm) to advance the first gear 110 (worm gear) only one tooth and a space of the first gearing component 224. It will be understood that different configurations of the first and second gearing components 224, 276 may be provided to obtain a desired speed reduction during the operation of the coupling assembly 100.
The rotation of the first gear 110 within the second housing bore 236 results in a progressive change in the engagement between the first threaded inner surface 228 of the first gear 110 and the threaded external surface 254 of the first shaft 102. As the first gear 110 remains in a substantially stationary position relative to the translational axis 350, the rotation of the threaded engagement between the first gear 110 and the first shaft 102 causes the first shaft 102 to progress through the first gear 110 and the second housing 108. The direction of the progression during the operation of the coupling assembly 110 is determined by a direction of rotation of second shaft 116, as discussed in more detail with reference to
The first bearing 230 is positioned radially between the second cylindrical portion 226 of the first gear 110, and a second inner circumferential wall 400 of the second housing 108. Outer circumferential surfaces of the first lip 223 and the second lip 225 are disposed radially inward of an engagement between the first bearing 230 and the second inner circumferential wall 400. As noted above, the diameter of each of the first and second lips 223, 225 may be equal to or greater than the diameter of an addendum circle or outer diameter defined by the first gearing component 224 of the first gear 110. Accordingly, none of the first gearing component 224, first lip 223, or the second lip 225 engages the second inner circumferential wall 400 (see also
Further, the first bearing 230 is positioned in second housing 108 as part of a configuration that limits an axial movement of the first gear 110. More specifically, the first bearing 230 is positioned on the second cylindrical portion 226 of the first gear 110 axially between the second lip 225, and a second combined wall defined by the second washer 232 and a third side wall 402 of the second housing 108. The second washer 232 may be fitted into an annular recess defined in the third side wall 402. In combination with an engagement between the first washer 214 and the first lip 223, engagements of opposite sides of the first bearing 230 with the second lip 225 and the second combined wall respectively, limits axial movement of the first bearing 230 during the operation of the of coupling assembly 100. Concurrently, an axial movement of the first gear 232 is limited by: (1) engagements of opposite sides of the first washer 214 with the first housing end-face 206 and the first lip 223 respectively; and (2) the engagement between the first bearing 230 and the second lip 225.
According to an aspect of the present disclosure, each of the first and second washers 214, 232 may be a thrust washer. The first bearing 230 and the first and second washer 214, 232 may dynamically limit (i.e. absorb and limit the transmission of) movement of the first gear 110 along the translational axis 350. Further, each of the first and second washers 214, 232 may be coated with a friction reducing coating, and/or formed of a material for which a coefficient of friction therewith is small (e.g. brass), to allow for relative rotational movement of the first gear 110.
With further reference to
The plug 244 is configured to guide the movement of the first shaft 102 within the first housing 106 and maintain a coaxial alignment between the first shaft body 250 and the first housing body 208. Thus, the plug 244 prevents the first shaft body 250 from drifting toward a side of first inner circumferential wall 422 (e.g. a bottom side) as the first shaft 102 progresses through the first housing 106. Such drifting may cause the first shaft body 250 to come in contact with first inner circumferential wall 422 in an unbalanced manner and impede movement of the first shaft 102, and cause the first shaft 102 to apply a torque to the components in second housing including the first gear 110. In addition, because the rim 414 has a greater diameter than an outer diameter of the threaded external surface 254 of the first shaft 102, the outermost surface of the first shaft body 250 may not contact (e.g. uniformly slide against) the first inner circumferential wall 422 of the first housing 106. Thus, a frictional surface area between the first shaft 102 and the first housing 106 is limited to the rim 414 of the plug 244. Accordingly, frictional resistance to the movement of the first shaft 102, as well as transmission of movement from the first shaft 102 to the first housing 106, is minimized. Further, wear to the threaded external surface 254 is reduced over time, and an operational life of the coupling assembly 100 may be optimized as a result.
As the movements of the first gear 110, the second gear 270, and the first shaft 102 are in effect, isolated from the first and second housings 106, 108, little or no force is required to maintain the coupling assembly 100 in a position to engage a tool, in particular a power driver, and be continuously operated without necessitating attempts by an operator to prevent the assembly from twisting away from the tool (by gripping a lever arm/handle bar or implementing other methods). Accordingly, while loads are connected in tension via respective connections with the screws 118 or with other devices (e.g. hooks) attached to the screws 118, an operator can operate the drive assembly 112 with a tool and the coupling assembly 100 will not move, or be required to be held with substantial effort so the tool remains engaged with the second shaft 116 and thereby the drive assembly 112. In other words, the coupling assembly 100 will not move away from the tool to the point of disengagement as a result of the movements of the components of the coupling assembly 100. Thus, the coupling assembly 100 can be used quickly because an operator: (1) does not have repeatedly reengage the tool with the second shaft 116; (2) does not risk physical injury trying to secure a twisting assembly housing; and (3) may be less likely to have to rest multiple times as a result of becoming fatigued from having to hold the coupling assembly 100 during an operation.
More simply, the second shaft is driven in a clockwise direction (first rotational direction 440), which causes the first gear 110 to rotate in a direction away from the plane indicated by section line 4-4 (second rotational direction 450). Rotation of the first gear 110 causes the shaft 102 to move in a direction away from (axial direction 460) the end wall 420 of the first housing 106 via the threaded engagement between the first gear 110 and the first shaft 102. As the first shaft 102 moves through the first housing 106, the rim 414 of the plug 244 slides along the first inner circumferential wall 422 and guides the movement of the first shaft 102.
In block S506, it may be determined whether a tension or length between loads is to be increased or reduced. If it is determined that the tension needs to be reduced/length increased, the second shaft 116 of the drive assembly 112 is driven in a first direction in block S508 to move the first shaft 102 in an axial direction away from the first housing 106, as in
If it is determined that the tension/length needs to be increased/reduced in length, the second shaft 116 of the drive assembly 112 is driven in a second direction in block S512 to move the first shaft 102 in an axial direction toward the first housing 106. In block S514 it is determined whether the plug 244 is in contact with the end wall 420 of the first housing 106.
If it is determined in blocks S510 or S514 that the plug 244 is in contact with the second housing 108 or the end wall 420 respectively, the method 500 may end. On the other hand, if it is determined in blocks S510 or S514 that the plug 244 is not in contact with the second housing 108 or the end wall 420 respectively, whether or not a desired tension/length between the connected loads will be evaluated in block S516. A result of the evaluation could result in the end of the method 500 or a determination in block S506 of whether the tension should be increased/length decreased between the connected loads.
It will be appreciated that the foregoing description provides examples of the disclosed coupling assembly and techniques for implementing the coupling assembly. These examples given above are merely illustrative and are not meant to be an exhaustive list of all possible designs, aspects, applications or modifications of the disclosure. Further, it is contemplated that other implementations of the disclosure may differ in detail from the foregoing examples. All references to the disclosure or examples thereof are intended to reference the particular example being discussed at that point and are not intended to imply any limitation as to the scope of the disclosure more generally. All language of distinction and disparagement with respect to certain features is intended to indicate a lack of preference for those features, but not to exclude such from the scope of the disclosure entirely unless otherwise indicated.
