Patent Publication Number: US-10766749-B2

Title: Portable winch

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     The present application claims priority to U.S. Provisional Patent Application No. 62/047,544, “PORTABLE WINCH,” filed on Sep. 8, 2014, the entire contents of which are hereby incorporated by reference for all purposes. 
    
    
     TECHNICAL FIELD 
     The present application relates to a portable pulling tool that can be actuated by an external source. 
     BACKGROUND AND SUMMARY 
     Heavy and cumbersome objects may need to be lifted and/or moved around garages, construction sites, farms, etc. As such, these objects may be heavy enough to require the use of equipment such as winches, hoists, or alternate pulling tools for moving and/or lifting. However, moving and hoisting equipment may be electrically operated and access to electricity may not be easily available at all sites. Accordingly, battery operable and/or externally actuatable moving and hoisting equipment may be desirable. 
     One example system for an externally actuatable winch is shown by Ying in U.S. Pat. No. 7,789,375. Herein, a portable winch assembly includes a planetary reduction gearbox with a primary sun gear configured to be coupled to and driven by a handheld torquing device such as an electric drill. Other than the primary sun gear, the planetary reduction gearbox further includes a first set of planet gears driven by the primary sun gear as well as a second set of planet gears driven by a secondary sun gear. The rotation of the primary sun gear and the planetary gear system enables rotation of a drum with a cable. 
     The inventors herein have identified potential issues with the above example system. Specifically, the portable winch assembly in U.S. Pat. No. 7,789,375 may be exposed to mechanical overload and resulting degradation. For example, torque provided by the handheld torquing device to the portable winch assembly may be amplified by the planetary reduction gearbox. The amplified torque may exceed structural design parameters of the portable winch assembly resulting in mechanical degradation of the assembly and its components. In addition, incorporating two sets of planetary gears for providing gear reduction may increase manufacturing costs of the portable winch assembly leading to higher costs for the consumer. 
     The inventors herein have recognized the above issues and identified various approaches to at least partly address the above issues. In one example approach, a system for a pulling tool is provided comprising a drum having an output end, an externally actuatable input shaft, an output driven shaft, a torque-limiting device positioned within the drum, the torque-limiting device including a torque-limiting mechanism situated between the externally actuatable input shaft and the output driven shaft, and a transmission including an input and a ring gear, the input coupled to the output driven shaft and the ring gear coupled to the output end of the drum. In this way, a pulling tool may be powered by external actuation while reducing incidences of torque overload. 
     For example, a pulling tool assembly may include a drum for winding a cable or wire rope. The drum may be positioned between a first end housing and a second end housing, and an output end of the drum may be configured with splined teeth. The drum may in turn include a torque-limiting device positioned within a spool of the drum. The torque-limiting device may include a torque limiter situated between an input drive shaft and an output driven shaft. The input drive shaft may be actuatable by an external actuator and may transmit applied torque to the output driven shaft via the torque limiter. The output driven shaft, in turn may be coupled to an input of a transmission. In one example, the input of the transmission may comprise a sun gear of a planetary gear set. Further, the transmission may include a differential planetary gear system. The transmission may further include a rotatable ring gear that meshes with the splined teeth on the output end of the winch drum. Rotational torque may be transmitted from the external actuator via the input drive shaft and output driven shaft to the transmission which in turn drives the drum to either release or retract the cable. 
     In this way, a pulling tool assembly may be actuated by an external device while reducing a likelihood of mechanical degradation by torque overload. By positioning the torque-limiting device between the input drive shaft and the output driven shaft, torque greater than a predetermined threshold may not be relayed to the transmission. Thus, the transmission may experience less degradation. Further, the pulling tool assembly may be operated as a handheld device as the torque-limiting device may reduce potential of torque overload. By using only a single set of differential planetary gears for torque amplification, the pulling tool assembly may have reduced manufacturing costs. Additionally, by not providing a motor within the pulling tool assembly and by using a planetary gear set and not a separate braking device, costs may be further reduced enabling the pulling tool assembly to be more affordable to a consumer. 
     It should be understood that the summary above is provided to introduce in simplified form a selection of concepts that are further described in the detailed description. It is not meant to identify key or essential features of the claimed subject matter, the scope of which is defined uniquely by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows a perspective view of an example pulling tool assembly as viewed from front, in accordance with the present disclosure. 
         FIG. 2  depicts a perspective view of the example pulling tool assembly of  FIG. 1  as viewed from a side. 
         FIG. 3  illustrates an exploded view of the example pulling tool assembly of  FIG. 1 . 
         FIG. 4  portrays a perspective view of a torque-limiting device within the example pulling tool assembly of  FIG. 1 . 
         FIG. 5  depicts a sectional view of a pulling tool drum within the example pulling tool assembly of  FIG. 1 , according to the present disclosure. 
         FIG. 6  shows a front view of the example pulling tool assembly of  FIG. 1 . 
         FIG. 7  presents a cross-sectional view of the example pulling tool assembly of  FIG. 6 . 
     
    
    
     DETAILED DESCRIPTION 
     The following detailed description provides information regarding a pulling tool assembly, such as the example pulling tool assembly of  FIGS. 1-7 , actuatable by an external actuator. The pulling tool described herein could be a variety of pulling tools including, but not limited to, a winch, as hoist, or an alternate pulling tool. Thus, while a winch may be described below, it should be noted that this is an example of a pulling tool and may also be used as a hoist or another type of pulling tool. The pulling tool assembly may include a drum positioned between two end housings (as shown in  FIG. 7 ), and a torque-limiting device may be situated within a spool of the drum (as shown in  FIG. 5 ). The torque-limiting device may be positioned between an externally actuatable input shaft and an output driven shaft (as shown in  FIG. 4 ). Further, the output driven shaft may drive a planetary gear transmission, which in turn may drive the drum (as shown in  FIG. 3 ). The pulling tool assembly may be used as a handheld tool or may also be attached to an external structure for stronger support when desired. 
     Regarding terminology used throughout this detailed description, torque-limiting device may also be referred to as a torque limiter or an overload limiter. Further, the drawings shown in  FIGS. 1-7  are drawn approximately to scale. Further, the pulling tool may also be referred to herein as a winch or hoist. 
       FIG. 1  depicts a perspective view of an example pulling tool (e.g., winch) assembly  70  (also termed winch  70 , herein). Specifically, perspective view  100  in  FIG. 1  illustrates a view from a front end of winch assembly  70 .  FIG. 2  depicts a perspective view  200  as observed from a first side of the winch assembly  70 . A description of  FIGS. 1 and 2  follows below. 
     Winch assembly  70  includes two end housings comprising a first end housing  110  and a second end housing  120  which may be mechanically coupled together. Coupling methods may include joining the first end housing  110  to second end housing  120  via bolts, rivets, screws, or other methods. The two end housings  110  and  120  may be coupled such that they may be dis-assembled for repair and/or replacement. It will also be noted that first end housing  110  and second end housing  120  may include additional components that may not be described in detail herein. 
     As depicted in  FIGS. 1 and 2 , the first end housing  110  is situated opposite the second end housing  120 , with respect to a centerline  80  of the winch assembly  70 , the centerline  80  being perpendicular to an axis of rotation  85  of the winch  70  (also referred to herein as a rotational axis or drum axis of the winch  70 ). The first end housing  110  forms a rear end of the winch assembly  70  and second end housing  120  forms a front end of the winch assembly  70 . A winch drum  170  is located within winch assembly  70 . Specifically, winch drum  170  may be positioned between first end housing  110  and second end housing  120 . However, winch drum  170  may be exposed towards its bottom surface. As such, winch drum  170  may be at least partially enclosed within the two end housings  110  and  120 . Winch drum  170  may comprise a first flange  171 , a second flange  172 , and a spool  175 . 
     Winch  70  may be a portable handheld device that may be gripped via handle  122 . As shown in  FIGS. 1-2 , the handle  122  may include a series of ridges  125  on a bottom surface facing toward the winch drum  170 , the ridges  125  formed to fit a user&#39;s fingers. Handle  122  may comprise a top flat portion  123  situated opposite the ridges  125  formed as finger holds. First end housing  110  and second end housing  120  may form a first inclined portion  132  and a second inclined portion  134  towards the top of winch assembly  70 . Handle  122  may be coupled in-between first inclined portion  132  and second inclined portion  134 . As such handle  122  may be attached to first inclined portion  132  at first end  136  and may be attached to second inclined portion  134  at second end  138 . First inclined portion  132  and second inclined portion  134  may be inclined in a direction parallel to centerline  80 . Handle  122  may, accordingly, extend from second inclined portion  134  to first inclined portion  132  in a direction parallel to centerline  80 . Further, first inclined portion  132  may angle away from second inclined portion  134  while second inclined portion  134  may be inclined towards first inclined portion  132 . As such, each of first inclined portion  132  and second inclined portion  134  incline away from a fairlead  150  which will be described below. 
     As shown in  FIGS. 1-2 , the handle  122  is positioned directly above the drum  170 . More specifically, the handle  122  is positioned at the centerline  80  and is centered along the drum axis  85 . Said another way, the handle  122  is positioned at the center of the winch, with respect to the drum axis  85 , and is thus centered over a center of the drum  170 . Further, the handle is positioned over a center of gravity of the pulling tool. For example, as seen in  FIG. 6  and described further below, a center portion of the handle  122  is shifted (e.g., angled) toward a back of the pulling tool. In this way, the handle  122  allows the winch to be handheld and the central positioning of the handle  122  keeps the winch level when being held and operated by a user. 
     As an alternative to being a handheld device, winch  70  may be mounted on or attached to an external support. As shown in  FIGS. 1 and 2 , a plurality of tie rods  112  are situated towards a first surface of the winch  70 . For example, the first surface of winch  70  may be a bottom surface (as shown in  FIGS. 1 and 2 ). Herein, the bottom surface may be below winch drum  170 . A strap or similar connecting device may be attached or hooked to the plurality of tie rods  112 , thereby enabling mounting of or attaching of winch  70  onto a support structure. In the embodiment of  FIGS. 1 and 2 , the plurality of tie rods  112  are located proximate to the bottom of the winch  70 , below the winch drum  170 . Further, the plurality of tie rods  112  are positioned proximate to a bottom of an interior surface of the two end housings  110  and  120 . The depicted embodiment includes two tie rods arranged below winch drum  170 . The two tie rods  112  at the bottom of winch assembly  70  substantially form a bottom surface of the winch  70 . While two tie rods  112  are shown in the given example, in other examples, a higher number or lower number of tie rods may be used. 
     As observed from  FIG. 2 , the plurality of tie rods  112  are spaced away from each other and are also spaced a distance from a bottom side of spool  175  of winch drum  170 , the bottom side ( 173  of  FIG. 3 ) of spool  175  opposite a top side ( 176  of  FIG. 3 ) of spool  175 , the top side ( 176  of  FIG. 3 ) closer to the handle  122  than the bottom side ( 173  of  FIG. 3 ). By arranging the plurality of tie rods  112  with substantial space between each other, and at substantial distance from a bottom side of spool  175  of winch drum  170 , the plurality of tie rods  112  may be accessible for easier attachment to an external support. To elaborate, each of plurality of tie rods  112  may be spaced away from each other such that an opening is formed at a bottom of the winch  70  between the two tie rods  112 , as shown in  FIG. 2 . It will be appreciated that the plurality of tie rods  112  may not have any other component included between each other. In other examples, additional tie rods may be placed between the two depicted tie rods  112 . Further, each of plurality of tie rods  112  may be spaced away from and below the base (or bottom surface) of spool  175  of winch drum  170 . No other component may be located between a tie rod and the base of the winch drum. Thus, the positioning of the plurality of tie rods away from each other, and at a distance from the bottom surface of the winch drum  170  enables ease of access for hooking a strap or a cable from an external support. Other embodiments may position the plurality of tie rods at different locations than shown in  FIGS. 1 and 2 . 
     The plurality of tie rods  112  may be coupled to each of the two end housings  110  and  120 . In one example, mechanical coupling methods may be utilized. Mechanical coupling methods may include joining via bolts, nuts, screws, rivets, etc. As such, each of the plurality of tie rods  112  may extend from the first end housing  110  to the second end housing  120 , and vice versa. To elaborate, each of the plurality of tie rods may have a first end  114  and a second end  116 . The first end  114  of each tie rod  112  may be attached to first end housing  110 , and the second end  116  of each tie rod  112  may be joined to second end housing  120 . Each of the plurality of tie rods  112  may be cylindrical. Alternatively, the plurality of tie rods  112  may have rectangular, square, or another cross section. In other embodiments, the tie structures  112  may be of different shapes including being thinner or thicker than depicted in  FIGS. 1 and 2 . 
     In addition to the plurality of tie rods  112  that may be used for securing winch assembly  70  to an external support, winch  70  may also include an anchor fixture (not indicated in  FIGS. 1 and 2 ) for connecting winch  70  to the external support. Anchor fixture will be described in more detail in reference to  FIG. 6  below. 
     As shown in  FIGS. 1-2 , a fairlead  150  is located on a side of winch  70  between the first end housing  110  and the second end housing  120 . Fairlead  150  may be coupled to each of the two end housings via one of several fastening methods including bolting, riveting, etc. Other coupling methods may also be used. Fairlead  150  is a distinct structural member of the winch assembly  70 . As such, fairlead  150  guides movement of a cable or wire rope as it is wound onto or unwound from a winch drum in the winch assembly. As shown in  FIGS. 1 and 2 , fairlead  150  extends from first end housing  110  to second end housing  120  in a direction parallel to the axis of rotation  85 . Accordingly, fairlead  150  may define a distance between first end housing  110  and second end housing  120 . Further, fairlead  150  includes a central opening (e.g., centrally positioned between an inner surface of the first end housing  110  and an inner surface of the second end housing  120 ) for passage of the cable or wire rope there through. Edges of the fairlead  150  surrounding the central opening may be chamfered (e.g., curved away from an interior of the winch) to provide a smoother surface and reduce wear on the cable as the cable passes through the central opening. The width of the opening of the fairlead  150  (e.g., in a direction of a long axis of the fairlead that extends from the front to rear end) is approximately the same as the width of the spool  175 . Additionally, the fairlead  150  may be made of cast iron with radius edges for greater wear resistance against the winch rope. Additionally, the curved edges and opening of the fairlead allows for proper spooling of the rope on the drum  170 . The fairlead height is narrow enough to keep a hook which may be coupled to an end of the rope from being pulled into the tool/drum. Further, as best seen in  FIG. 5 , described in further detail below, the drum  170  has a large amount of freeboard (e.g., the distance between the drum or top layer of rope wound around the drum and the outside of the drum flanges  171  and  172 . Additionally, the center of the opening of the fairlead  150  is positioned vertically above the axis of rotation  85  of the drum  170 . As such, the fairlead  150  is positioned closer to a top surface  127  of the winch  70  than the bottom surface formed by the tie rods  112 . As explained further below, the top surface  127  is positioned between the winch drum  170  and the handle  122 . 
     Second end housing  120  includes a front circular frame end  160  (e.g., first end cap) which in turn may include a rotatable dial  162 . Winch  70  may be unlocked by rotating dial  162  between a locked position  164  and an unlocked position  166 . When in the locked position, winch assembly  70  may not be back-drivable so that a load may be held when external actuation is stopped. To release the load and enable free spooling, winch assembly  70  may be unlocked by rotating dial  162  to unlocked position  166 . 
     A window  124  may also be included on the top surface  127  of winch assembly  70  for viewing cable movement and spooling. The window  124  may be formed across the top, outward-facing surface, with respect to the winch drum  170 . For example, window  124  may be positioned in the top, outward-facing surface of both the first end housing  110  and the second end housing  120 . As such, the window  124  extends across the top, outward-facing surface, in a direction of the axis of rotation of the winch  70 , from the first end housing  110  to the second end housing  120 . In this way, the window  124  may be positioned above the winch drum  170  in order to allow a user to view the winch drum  170 . Window  124  may also be situated underneath handle  122  and between first inclined portion  132  and second inclined portion  134 . As such, the window  124  is positioned between the drum  170  and the handle  122 . The window  124  allows the winch drum  170  to be readily visible to user, while at the same time protecting a user&#39;s fingers when gripping the winch via the handle  122 . 
     First end housing  110  includes a rear circular frame end  140  (e.g., second end cap) which may be configured with a central circular opening. A portion of an externally actuatable input drive shaft may project outwards through central circular opening of rear circular frame end  140 . As shown in  FIG. 2 , second end  282  of externally actuatable input drive shaft  264  (not shown in  FIGS. 1 and 2 ) protrudes outside of a rear portion of winch assembly  70  where it may be coupled to an external actuator, e.g. a battery powered drill. 
     Thus, an example assembly for a portable winch may comprise two end housings coupled to each other. A winch drum may be positioned within the two end housings wherein the winch drum includes an input side and an output side. A plurality of tie rods may be mechanically coupled to the two end housings and the plurality of tie rods may be positioned around a first side (e.g. bottom side) of the winch drum. Further, a fairlead may be located between the two end housings and may be coupled to each of the two end housings. The example assembly may also include a space between the tie rods and a bottom surface of the winch drum allowing access for hooking the tie rods to a support. Furthermore, the example assembly may also comprise an anchor fixture to attach the portable winch to an external support. As will be explained below, a torque limiting device or a torque limiter may also be included inside the winch drum of the example assembly. 
     Turning now to  FIG. 3 , it shows an exploded view  300  of winch assembly  70 . First end housing  110  towards the rear end of winch assembly  70  is shown towards the extreme right hand side of exploded view  300 . Second end housing  120  with front circular frame end  160  towards the front end of winch assembly  70  is shown at the extreme left hand side of the exploded view  300 . Various components that may be enclosed within the two end housings  110  and  120  are portrayed in between. It will be noted that all components that are depicted in exploded view  300  may not be described. 
     As mentioned earlier in reference to  FIGS. 1 and 2 , winch  70  may include winch drum  170  which comprises first flange  171 , second flange  172 , and spool  175 . Second flange  172  may include an output end  177  of winch drum  170 . As will be observed, output end  177  of winch drum  170  has a plurality of teeth  208 . Plurality of teeth  208  may also be termed splined teeth  208  herein. Plurality of teeth  208  may be cast onto the output end  177  of the winch drum  170 , or alternatively may be machined onto the output end  177 . Winch  70  also includes transmission  210 . In the example shown, the transmission  210  is a differential planetary gear train system. Transmission  210 , therefore, may comprise sun gear  214 , a plurality of planet gears  212 , a fixed ring gear  216 , and a rotatable ring gear  218 . The planet gears  212  may be affixed between carrier plates (not indicated). Further, each of the plurality of planet gears  212  may include two sets of teeth formed in a stepped manner. A first set of teeth on each of the plurality of planet gears  212  may mesh with fixed ring gear  216  while a second set of teeth on each of the plurality of planet gears  212  may mesh with rotatable ring gear  218 . It will be appreciated that fixed ring gear  216  and rotatable ring gear  218  may have a different number of teeth. Rotatable ring gear  218  of transmission  210  may engage plurality of teeth  208  on the output end  177  of winch drum  170 . Thus, torque provided to an input (sun gear  214 ) of transmission  210  may be transmitted to winch drum  170  via rotatable ring gear  218  meshing with splined teeth  208  on winch drum  170 . 
     Transmission  210  may receive input torque from an output driven shaft  262  which may be coupled via a torque-limiting device  250  to input drive shaft  264 . Torque-limiting device  250  may include a torque-limiting mechanism  251  which will be described later. The input drive shaft  264  is actuatable by an external actuator. In one example, the external actuator may be a handheld battery powered actuator. Second end  282  of input drive shaft  264  is adapted to be coupled to the external actuator, and thus, may receive torque from the external actuator when the external actuator is coupled to the second end  282 . 
     At least a portion of input drive shaft  264  located opposite second end  282  may be splined. As shown in  FIG. 3 , a first end  266  of input drive shaft  264  is splined. As such, the splined portion of first end  266  of input drive shaft  264  may fit into torque-limiting device  250 . Torque-limiting mechanism  251  of torque-limiting device  250  may include a first cam  252  and a second cam  254 , which may be held together by a compression spring  256 . Specifically, splined portion of first end  266  of input drive shaft  264  may fit into first cam  252  of torque-limiting mechanism  251 . Output driven shaft  262  may be attached to second cam  254  and also may be supported by needle bearing  258 . In the depicted example, output driven shaft  262  may be a d-shaft. First cam  252  and second cam  254  may interlock with each other enabling transmission of torque from input drive shaft  264  to output driven shaft  262 . Further details of the torque-limiting device  250  will be explained below in reference to  FIG. 4 . 
     The input drive shaft  264 , torque-limiting device  250  (or overload limiter  250 ), and output driven shaft  262  may be substantially enclosed within winch drum  170 . Specifically, spool  175  of winch drum  170  may completely surround torque-limiting device  250 , and substantially enclose the input drive shaft  264  and output driven shaft  262 . For example, a significant portion of each of the input drive shaft  264  and output driven shaft  262  may be situated within spool  175  of winch drum  170  while a relatively smaller portion of each of the two shafts may protrude outside of spool  175 . As will be shown and described in reference to  FIG. 5 , at least a portion of input drive shaft  264  may extend outside of winch drum  170  to enable coupling with an external actuator. Further, a section of output driven shaft  262  may project outwards of winch drum  170  to provide coupling with transmission  210 . In contrast to the input drive shaft  264  and output driven shaft  262 , torque limiting device  250  may be fully enclosed within spool  175  of winch drum  170 . 
     Torque from the external actuator may be used to rotate winch drum  170  to enable winding and unwinding of a cable. The external actuator, such as a battery powered drill, may be coupled to second end  282  of input drive shaft  264 . Upon actuation of the external actuator, input drive shaft  264  may rotate (e.g., rotate with rotation of the external actuator) and in turn transmit applied torque to output driven shaft  262  via torque-limiting device  250 . To elaborate, input drive shaft  264  may drive first cam  252 , which being interlocked with second cam  254  may drive second cam  254 . Output driven shaft  262  may then be propelled by second cam  254 . The rotation of output driven shaft  262  may be transmitted to sun gear  214  of transmission  210 . Sun gear  214  may then drive the plurality of planet gears  212  which may transmit their rotation to rotatable ring gear  218 . Winch drum  170  may then be rotated as the plurality of teeth  208  mesh with rotatable ring gear  218 . 
     As one example, the input drive shaft  264  and drum  170  are arranged so that they turn clockwise to power the winch in (e.g., wind a rope or cable into and around the drum). For example, if the external actuator is a drill, the drill turns clockwise, thereby rotating the input drive shaft  264  and, as a result, the drum, clockwise. Since drills have a performance bias in the clockwise direction, powering the winch in, in the clockwise direction, may provide an increased amount of input torque. As a result, the winch rope or cable is powered into and wound around the drum via the power from the drill. In this way, the winch does not include a motor or another type of internal power source inside the winch. Instead, the winch drum is powered by the external power source. Further, the clockwise direction of the winch power-in operation allows the rope to be wound onto the drum at the top of the drum. Further, the arrangement of the input drive shaft  264  at the rear side of the winch allows for a left side input when being held by a user. For example, during winch operation, a user may hold the winch via the handle  122  with their right hand while they hold the external drive source (e.g., drill) with their left hand against the input drive shaft  264 . In this way, the user may stand behind the winch (e.g., opposite the fairlead), so that the fairlead faces away from the user and is exposed to whatever is being pulled or hoisted. As such, the relative arrangement of the fairlead, handle, and input drive shaft  264  provides for a winch that is easier to hold and operate. In an alternate embodiment, the input drive shaft  264  and drum  170  may be arranged so that they turn counterclockwise to power the winch in. 
     It will be appreciated that transmission  210  in winch assembly  70  may not be back-drivable. For example, transmission  210  may not be back-driven due to a high ratio in the differential planetary transmission which enables a higher back driving friction. Herein, fixed ring gear  216  may also be attached to second end housing  120  to provide a reaction force load path and to reduce free-spooling. Fixed ring gear  216  may be coupled to second end housing  120  such that it restrains a reverse rotation of transmission  210  including the differential planetary gear train and therefore, the winch drum  170 . 
     Instead, reverse rotation, or free-spooling, of the winch drum may be enabled by a clutch and clutch lock mechanism. For example, reverse rotation of winch assembly  70  may be enabled by unlocking fixed ring gear  216  from clutch housing  222 . Referring to  FIGS. 1 and 3 , dial  162  may be rotated to unlocked position (e.g., free spool position)  166  so that each of spring pins (e.g., clutch pins)  228  may be raised from their respective position within leaf springs  224  and  226 . By raising spring pins  228  to transition into the free spool position, the fixed ring gear  216  may be uncoupled from clutch housing  222  enabling a reverse rotation and free spooling of winch assembly  70 . As such, the clutch (e.g., clutch mechanism) of the winch may include the clutch pins  228 , leaf springs  224  and  226 , and dial (e.g., clutch lock). The leaf springs  224  and  226  may be mounted to an interior of the clutch dial  162  via screws  229 . The fixed ring gear  216  is located within the clutch housing  222 . Further, the leaf springs  224  and  226  may be coupled to the clutch housing  222  via the clutch pins  228 . 
     The spring pins  228  each include a return spring. For example, by rotating the dial  162 , the spring pins  228  are retracted by the returns springs. The return springs provide a minimal retraction force on the spring pins  228  and therefore limit the load under which the winch can be shifted into the free-spool position. For example, the load limit may be set to be no greater than 3% of the winch capacity rating. In this way, the clutch cannot be disengaged (e.g., moved into the free-spool mode) when a load above a threshold load (as determined by the stiffness of the return springs) is being applied to the winch. Upon reengagement of the clutch (e.g., the fixed ring gear  216 ), the leaf springs  224  and  226  deflect if the clutch pins  228  are not aligned with the corresponding grooves in the fixed ring gear  216 . This allows the engagement to be delayed until they are aligned. Alignment occurs when the notches in the fixed ring gear  216  align with the clutch pins  228 . When the clutch pins  228  align with the fixed ring gear notches the pins drop into the fixed ring gear notches effectively locking the fixed ring gear  216 . When the fixed ring gear  216  is locked the geartrain is engaged and therefore the tool can again pull. 
       FIG. 3  also includes the plurality of tie rods  112  which in the depicted example are two in number. As described earlier in reference to  FIGS. 1 and 2 , plurality of rods  112  may be positioned at the bottom surface of winch assembly  70 . To elaborate, plurality of tie rods  112  can be positioned below bottom side  173  of spool  175  of winch drum  170 . Bottom side  173  of spool  175  is opposite to the top side  176  of spool  175 , the top side  176  being closer to window  124  (and the handle  122 ) than the bottom side  173 . An internal support  118  may also be included within winch assembly  70 . In one example, internal support  118  may be shaped similar to tie rods  112  and may be a rod-like cylindrical structure. Other shapes for internal support  118  have been contemplated. Unlike plurality of tie rods  112 , internal support  118  may be coupled to first end housing  110  and second end housing  120  towards the top of winch assembly  70 . Internal support  118  may be situated closer to handle  122  and window  124  than plurality of tie rods  112 . As such, internal support  118  may not be positioned below bottom side  173  of spool  175  of winch drum  170 . Further, internal support  118  may be located on a side of winch assembly  70  that is opposite to fairlead  150  relative to axis of rotation  85 . Internal support  118  may function as an additional brace to a frame of winch assembly  70 . In alternate embodiments, the winch  70  may not include the internal support  118 . 
     A shield  272  to protect winch drum  170  from debris is also portrayed at the extreme right hand side of  FIG. 3 . Shield  272  may be coupled to first end housing  110  within central circular opening of rear circular frame end  140 . Fairlead  150 , as mentioned earlier, may be a distinct structural piece of winch assembly  70 , the fairlead  150  defining a distance between an exterior wall of first end housing  110  and an exterior wall of second end housing  120 . 
     As illustrated in  FIG. 3 , first end housing  110  may cap winch drum  170  at a first side towards first flange  171  while second end housing  120  may cap winch drum  170  at a second side towards second flange  172 . Further, the first side and the second side may be located opposite each other. To elaborate, first flange  171  and second flange  172  are positioned opposite each other. 
     It will also be appreciated that an internal motor (or another type of internal power source) is not included within winch assembly  70 . Therefore, operation of the winch  70  may not be possible without an external actuator. Accordingly, torque to drive the winch assembly  70  may only be provided via external actuation to the externally actuatable input drive shaft  264 . 
     O-ring  292  may enable sealing between winch drum  170  and first end housing  110 . Further, O-ring  292  may reduce water and dust intrusion into the winch assembly  70 . Additional seals as well as other components may also be incorporated in winch assembly  70  without departing from the scope of the present disclosure. For example, an additional O-ring (e.g., O-ring  299  shown in  FIG. 7 ) may be positioned within an O-ring groove  297  in the first end housing  110 . It will be noted that winch assembly  70  may include additional components shown in  FIG. 3  that are not described in this disclosure. As an example, a cable or wire rope may be wound onto winch drum  170  within winch assembly  70  that is not depicted in any of the figures. 
     Turning now to  FIG. 4 , a perspective view of torque-limiting device  250  is illustrated herein. Torque-limiting device  250  may comprise torque-limiting mechanism  251 , compression spring  256 , and spring cap  274 . Torque-limiting mechanism  251  may include a first cam  252  and a second cam  254 . The first cam  252  may be termed a driver cam since input drive shaft  264  may be fitted into, and drive, the first cam  252 . First cam  252  may be interlocked with second cam  254 . Each of the first cam  252  and the second cam  254  may be formed with ramps that oppose each other. Specifically, ramps  452  formed on a first mating surface  294  of first cam  252  may interlock with opposing ramps  454  formed on a second mating surface  296  of second cam  254 . First mating surface  294  of first cam  252  may face second mating surface  296  of second cam  254 , as shown. Ramps  452  and ramps  454  may have opposing angles. Further, ramps  452  and  454  may be formed with specific angles based on a desired torque overload limit. As an example, the angles of ramps  452  and  454  may be different for a lower limit of torque overload than angles chosen for a higher torque overload limit. 
     First cam  252  may, thus, intermesh with second cam  254  via ramps  452  and  454 . Further, first cam  252  may be pressed against second cam  254  by compression spring  256  which may be held by spring cap  274 . As such, compression spring  256  presses directly against first cam  252 . First cam  252  may press against second cam  254  with a force that may be determined by a spring constant of compression spring  256 . In one example, compression spring may be further loaded by twisting a pair of jam nuts  268  against spring cap  274 . Thus, first cam  252  may be interlocked with second cam  254  at a pressure dependent upon a load from jam nuts  268 . In this example, torque-limiting device  250  may include torque-limiting mechanism  251 , with first cam  252  and second cam  254 , compression spring  256 , spring cap  274 , and jam nuts  268 . In other examples, jam nuts  268  may not be included and first cam  252  and second cam  254  may be forced together at a pressure based only on the spring constant of compression spring  256 . 
     Torque may be transmitted from input drive shaft  264  to first cam  252  and thereon, to second cam  254 . If the torque driving first cam  252  exceeds a specific design factor, first cam  252  may ramp up and over ramps  454  of second cam  254 . The specific design factor may be a predetermined torque threshold (e.g., also referred to herein as a load limit or threshold). As such, the first cam  252  may be decoupled from second cam  254  when the predetermined torque threshold is exceeded. The torque-limiting capacity of the torque-limiting device  250  may be a function of ramp angles in the two cams, surface area that is interlocked between the two cams, material of the cams, cam height, friction between cam surfaces and spring force of compression spring  256 . Upon exceeding the predetermined torque threshold, first cam  252  may separate from second cam  254  and may be forced axially towards compression spring  256 . After a decoupling event the force provided by compression spring  256  forces first cam  252  to reengage with second cam  254  and allow torque transfer from input drive shaft  264  to output driven shaft  262 . 
     Spring cap  274 , compression spring  256 , and jam nuts  268  (if present) may be mounted on first end  266  (not shown in  FIG. 4 ) of input drive shaft  264  that includes a splined portion. First cam  252  may also be mounted on the splined portion of input drive shaft  264 . As such, first end  266  of input drive shaft  264  may be splined to reduce friction from axial movement of first cam  252  as it decouples from second cam  254  during a torque overload condition. 
     As shown in  FIG. 4 , needle bearing  258  may be mounted on output driven shaft  262  adjoining second cam  254 . Needle bearing  258  may be a thrust bearing to resist thrust forces received from second cam  254 . Output driven shaft  262  may be further mounted in a bushing  276  which is positioned adjacent to needle bearing  258 . Output driven shaft  262  may rotate within and be supported by needle bearing  258  and bushing  276 . As will be observed n  FIG. 5 , needle bearing  258  and bushing  276  may be supported by winch drum  170 . An output end  261  of output driven shaft  262  may be coupled to input (e.g. sun gear  214 ) of transmission  210 . The needle bearing  258  allows the torque limiting mechanism  251  to rotate relative to the winch drum while axial thrust is generated by compression of spring  256 . As such, friction from axial forces produced along the torque limiting mechanism  251  are reduced, thereby allowing various speed differentials. 
       FIG. 5  portrays a sectional view  500  of winch drum  170  indicating a positioning of input drive shaft  264 , torque-limiting device  250 , and output driven shaft  262  within spool  175  of winch drum  170 . 
     Winch drum  170  may be at least partially hollow to accommodate torque-limiting device  250  as well as input drive shaft  264  and output driven shaft  262 . Each of input drive shaft  264  and output driven shaft  262  may protrude beyond first flange  171  and second flange  172  respectively, of winch drum  170 . Specifically, second end  282  of input drive shaft  264  may extend beyond first flange  171  such that it is exposed towards rear end of winch assembly  70  to enable coupling to an externally actuating device. However, torque-limiting device  250  may be completely enclosed within spool  175  of winch drum  170 . To elaborate, torque-limiting device  250  may not protrude beyond either first flange  171  or second flange  172  of winch drum  170 . Further, input drive shaft  264 , torque-limiting device  250 , and output driven shaft  262  may be situated in an axial direction of the winch drum  170  (e.g., in a direction of the axis of rotation  85  of the winch). Further still, input drive shaft  264 , torque-limiting device  250 , and output driven shaft  262  may be situated along a centrally axial direction of the winch drum  170 . 
     Sectional view  500  of  FIG. 5  also depicts the positioning of torque-limiting device  250  in between input drive shaft  264  and output driven shaft  262 . As described earlier in reference to  FIG. 4 , torque-limiting device  250  may include torque-limiting mechanism  251 , with first cam  252  and second cam  254 , compression spring  256 , and spring cap  274 . Some embodiments may also include jam nuts  268  (not shown in  FIG. 5 ) situated adjacent to spring cap  274 . As elaborated earlier, first cam  252  and second cam  254  may be interlocked with each other via opposing ramps. One set of ramps  454  on second mating surface  296  of second cam  254  can be observed in sectional view  500  locked into a valley  295  on first mating surface  294  of first cam  252 . 
     Output driven shaft  262  may rotate within needle bearing  258  and bushing  276 . Each of needle bearing  258  and bushing  276  may be held by winch drum  170 . Thus, at least a portion of output driven shaft  262  may be supported by winch drum  170 . Splined teeth  208  (or plurality of teeth  208 ) may be cast onto output end  177  of winch drum  170  for meshing with rotatable ring gear  218  of transmission  210 . 
     Turning now to  FIGS. 6 and 7 , they portray a front view  600  of winch assembly  70  as viewed from its front end, and a sectional view  700 . Sectional view  700  is a cross-sectional view of winch assembly  70  in a cross sectional plane along line A-A of  FIG. 6 . Sectional view  700  further shows a cross sectional view along the length of winch assembly  70  from its front end to its rear end. 
     An anchor fixture  126  is depicted on a side in front view  600 . It will be noted that anchor fixture  126 , in the depicted example, is located on the side opposite fairlead  150  (e.g., opposite with respect to the winch drum). Anchor fixture  126  may be used to attach portable winch  70  to an external support via a hook, strap, wire rope, cable, or other means. Anchor fixture  126  may thus provide an additional mode, other than plurality of tie rods  112 , to attach winch assembly  70  to an external support. 
     Dial  162  on front circular frame end  160  of second end housing  120  is also shown in  FIG. 6 . It will be appreciated from front view  600  that dial  162  may be rotated between locked position  164  and unlocked position  166  to lock and unlock the transmission  210  for restraining or allowing reverse rotation. In the locked position, winch assembly  70  may hold static load when the external actuator is inoperative. In the unlocked position, winch assembly  70  may be rotated in a reverse direction (e.g. reverse to direction when winding or retracting a cable) to unwind the cable. 
     Front view  600  also depicts handle  122  of winch assembly  70  that enables winch  70  to be used as a handheld device. Handle  122 , as described earlier in reference to  FIGS. 1 and 2 , may be positioned towards the top of winch assembly  70 , opposite to the bottom surface of winch assembly  70 . Handle  122  may be a cylindrical shaped structure with top flat portion  123  opposite the series of ridges  125  (or finger holds  125 ). Ridges  125  may be fashioned as grooves to enable fitting to a user&#39;s fingers. Also, as described earlier in reference to  FIG. 1 , handle  122  may be coupled in-between first inclined portion  132  and second inclined portion  134 . First inclined portion  132  and second inclined portion  134  may be formed by coupling first end housing  110  and second end housing  120  to each other. 
     Handle  122  may be attached to first inclined portion  132  at first end  136  and may be attached to second inclined portion  134  at second end  138 . First inclined portion  132  and second inclined portion  134  may be inclined in a direction parallel to each other and parallel to centerline  80 . Further, first inclined portion  132  may angle away from second inclined portion  134  while second inclined portion  134  may be inclined towards first inclined portion  132 . As such, each of first inclined portion  132  and second inclined portion  134  incline away from fairlead  150 . Further, each of first inclined portion  132  and second inclined portion  134  incline towards anchor fixture  126 . Handle  122  may also extend along a width of the end housings  110  and  120 . 
     Window  124  is also depicted coupled towards the top of winch assembly  70 . Window  124  may be positioned underneath handle  122 . Further, window  124  may be located vertically above the winch drum  170  to observe spooling of the cable onto winch drum  170 . 
     Sectional view  700  in  FIG. 7  includes sectional view of winch drum  170  as well as sectional views of the two end housings  110 ,  120 , and additional components that form the framework of winch assembly  70 . 
     As described earlier in reference to  FIGS. 3-6 , winch assembly  70  may include first end housing  110  and a second end housing  120 . Winch drum  170  may be positioned in an intermediate location between first end housing  110  and second end housing  120 . Specifically, first end housing  110  may cap (e.g., enclose) a first side of winch drum  170  and second end housing  120  may cap (e.g., enclose) a second side of the winch drum  170 . To elaborate further, rear circular frame end  140  of first end housing  110  may cap winch drum  170  towards the rear of winch assembly  70 . Further, front circular frame end  160  of second end housing  120  may cap winch drum  170  towards the front of winch assembly  70 . As such, the first end housing  110  and second end housing  120  may fully enclose the internal components of winch assembly  70 . 
     Externally actuatable input drive shaft  264 , torque-limiting device  250 , and output driven shaft  262  may be positioned in a central axial position within winch drum  170  and winch assembly  70 , along axis of rotation  85  of the winch. Second end  282  of externally actuatable input drive shaft  264  may project slightly beyond rear circular frame end  140 . Output end  261  of output driven shaft  262  may be coupled to sun gear  214  of transmission  210 . As such, output end  261  may be fitted into sun gear  214 . Further, each of the plurality of planet gears  212  may mesh with sun gear  214  and with ring gear  218 . Ring gear  218  may not be fixed and may rotate to transmit rotational motion from planet gears  212  to winch drum  170  via splined teeth  208  on output end  177  of winch drum  170 . 
     By positioning torque-limiting device  250  in-between input drive shaft  264  and output driven shaft  262 , torque-limiting features of winch assembly  70  may be enhanced. Torque-limiting device  250  may comprise torque-limiting mechanism  251  (including first cam  252  and second cam  254 ), compression spring  256 , and spring cap  274 . In some embodiments, torque-limiting device  250  may also include jam nuts  268  to provide additional load on first cam  252  and second cam  254 . 
     It will be appreciated that torque-limiting device  250  provided within winch assembly  70  may be in addition to a torque limiter that may be present in the external actuator. Thus, operation of the winch assembly  70  may be enhanced. 
     Sectional view  700  also depicts one of the plurality of tie rods  112  extending between first end housing  110  and second end housing  120 . Tie rod  112  may be positioned towards a first side (e.g. bottom surface) of winch assembly  70 . As will be observed, tie rod  112  is placed below or towards an underside of winch drum  170 . Further still, a space “D” may be present between tie rod  112  (shown in  FIG. 7 ) and underside of winch drum  170 . Space “D” between tie rod  112  and base of winch drum  170  may allow easier access to the plurality of tie rods  112 . Additionally,  FIG. 7  depicts O-rings seals  292  and  299 , as described above. 
     Thus, an assembly for a winch may include a winch drum having an output end, an externally actuatable input drive shaft, and an output driven shaft. A torque-limiting device may be positioned within the winch drum wherein the torque-limiting device included a torque-limiting mechanism situated between the externally actuatable input drive shaft and the output driven shaft. The assembly may further include a transmission which comprises an input and a ring gear. The input of the transmission may be coupled to the output driven shaft while the ring gear may be coupled to the output end of the winch drum. The externally actuatable input drive shaft may include a splined shaft at a first end wherein the first end is coupled to the torque-limiting mechanism. 
     The transmission may comprise a differential planetary gear train including the ring gear, the ring gear meshing with a plurality of teeth on the output end of the winch drum. The differential planetary gear train may have a higher resistance to being back-driven. Thus, the transmission in the assembly may not be back-drivable. Further, a cable wound onto the winch drum may be unwound by reversing rotation of the input drive shaft via external actuation. Alternatively, reverse rotation of the differential planetary gear train and winch drum may also be enabled by unlocking a fixed ring gear of the transmission. 
     In another example, a winch assembly may include a first end housing, a second end housing, and a winch drum, with splined teeth on an output end, positioned between the first end housing and the second end housing. An input drive shaft adaptable to being externally actuated and an output driven shaft driving a differential planetary gear train may also be included in the winch assembly. The differential planetary gear train may comprise a rotatable ring gear, the rotatable ring gear meshing with the splined teeth on the output end of the winch drum. Further, a torque-limiting device may be enclosed within the winch drum. The torque-limiting device may comprise a spring loaded cam mechanism and may be placed in-between the input drive shaft and the output driven shaft. 
     In yet another example, a winch assembly may comprise two end housings coupled to each other with a winch drum positioned within the two end housings, the winch drum including an output side. The winch assembly may further include a torque-limiting device positioned inside the winch drum. Further still, a plurality of tie rods may be coupled to the two end housings, the plurality of tie rods positioned around a first side of the winch drum. Additionally, a fairlead may be located between the two end housings and may be coupled to each of the two end housings. 
     In an additional example, an assembly for a winch may include a winch drum with an output side, and a torque-limiting device positioned inside the winch drum. The assembly may also include two end housings coupled to each other and wherein, the winch drum may be positioned within the two end housings. Additionally, a plurality of tie rods may be coupled to the two end housings, the plurality of tie rods positioned around a first side of the winch drum. Further still, a fairlead may be located between the two end housings and may be coupled to each of the two end housings. 
     In another embodiment, a winch may comprise a winch drum with an output side, a torque-limiting device positioned inside the winch drum, and a plurality of tie rods, the plurality of tie rods positioned around a first side of the winch drum. The winch may further include two end housings coupled to each other such that the winch drum may be positioned within the two end housings. Additionally, the plurality of tie rods may be coupled to the two end housings. Further still, a fairlead may be located between the two end housings and may be coupled to each of the two end housings. 
     In yet another embodiment, an assembly may comprise a winch drum positioned within two end housings, and a plurality of tie rods, the plurality of tie rods positioned around a first side of the winch drum. The two end housings may be coupled to each other. Further, the plurality of tie rods may be coupled to the two end housings. The assembly may further include a torque-limiting device positioned inside the winch drum. Further still, a fairlead may be located between the two end housings and may be coupled to each of the two end housings. 
     In an additional embodiment, an assembly may comprise two end housings coupled to each other, a winch drum positioned within the two end housings, a torque limiting device positioned inside the winch drum, and a plurality of tie rods coupled to the two end housings, the plurality of tie rods positioned around a first side of the winch drum. The assembly may further include a fairlead located between the two end housings and coupled to each of the two end housings. 
     In a further embodiment, an assembly may comprise two end housings coupled to each other, a winch drum positioned within the two end housings, a torque limiting device positioned inside the winch drum, and a fairlead located between the two end housings and coupled to each of the two end housings. The assembly may further include a plurality of tie rods coupled to the two end housings, the plurality of tie rods positioned around a first side of the winch drum. 
     In a different example, a winch may comprise a winch drum, an externally actuatable input shaft, and an output driven shaft. The winch may further include a torque-limiting device positioned within the winch drum. Furthermore, the torque-limiting device may comprise a torque-limiting mechanism situated between the externally actuatable input shaft and the output driven shaft. Further still, the winch may include a transmission including an input and a ring gear, the input coupled to the output driven shaft and the ring gear coupled to an output end of the winch drum. 
     In another different example, an assembly may comprise a winch drum, an externally actuatable input shaft, an output driven shaft, and a torque-limiting device. The torque-limiting device may be positioned within the winch drum. The torque-limiting device may further comprise a torque-limiting mechanism situated between the externally actuatable input shaft and the output driven shaft. Further still, the winch may include a transmission including an input and a ring gear, the input coupled to the output driven shaft and the ring gear coupled to an output end of the winch drum. 
     In yet another different example, an assembly may comprise a winch drum, an externally actuatable input shaft, an output driven shaft, and a transmission including an input and a ring gear, the input coupled to the output driven shaft and the ring gear coupled to an output end of the winch drum. The winch may further include a torque-limiting device positioned within the winch drum. Furthermore, the torque-limiting device may comprise a torque-limiting mechanism situated between the externally actuatable input shaft and the output driven shaft. 
     In a different embodiment, an assembly may comprise a winch drum, an externally actuatable input shaft, an output driven shaft, and a transmission. The transmission may include an input and a ring gear, the input coupled to the output driven shaft and the ring gear coupled to an output end of the winch drum. The winch may further include a torque-limiting device positioned within the winch drum. Furthermore, the torque-limiting device may comprise a torque-limiting mechanism situated between the externally actuatable input shaft and the output driven shaft. 
     In a further embodiment, an assembly may comprise a winch drum, and a transmission. The assembly may also include an externally actuatable input shaft, an output driven shaft. The transmission may include an input and a ring gear, the input coupled to the output driven shaft and the ring gear coupled to an output end of the winch drum. The winch may further include a torque-limiting device positioned within the winch drum. Furthermore, the torque-limiting device may comprise a torque-limiting mechanism situated between the externally actuatable input shaft and the output driven shaft. 
     In yet another embodiment, a winch assembly may comprise a first end housing, a second end housing, a winch drum, with splined teeth on an output end, positioned between the first end housing and the second end housing, an input drive shaft adaptable to being externally actuated, and an output driven shaft driving a differential planetary gear train. The differential planetary gear train may comprise a rotatable ring gear, the rotatable ring gear meshing with the splined teeth on the output end of the winch drum. The winch assembly may further include a torque-limiting device enclosed within the winch drum and comprising a spring loaded cam mechanism, the torque-limiting device placed in between the input drive shaft and the output driven shaft. 
     In a different example, a winch assembly may comprise a winch drum, with splined teeth on one end, positioned between a first end housing and a second end housing, an input drive shaft adaptable to being externally actuated, and an output driven shaft. The winch assembly may further include a differential planetary gear train being driven by the output driven shaft. The differential planetary gear train may comprise a rotatable ring gear, the rotatable ring gear meshing with the splined teeth on the one end of the winch drum. The winch assembly may further include a torque-limiting device enclosed within the winch drum and comprising a spring loaded cam mechanism, the torque-limiting device placed in between the input drive shaft and the output driven shaft. 
     In another different example, an assembly may comprise a winch drum, with splined teeth on one end, an input drive shaft adaptable to being externally actuated, and an output driven shaft. The assembly may further include a differential planetary gear train being driven by the output driven shaft. The differential planetary gear train may comprise a rotatable ring gear, the rotatable ring gear meshing with the splined teeth on the one end of the winch drum. The assembly may further include a torque-limiting device enclosed within the winch drum and comprising a spring loaded cam mechanism, the torque-limiting device placed in between the input drive shaft and the output driven shaft. The assembly may also include a first end housing and a second end housing such that the winch drum with splined teeth may be positioned between the first end housing and the second end housing. 
     In this way, a pulling tool assembly (such as a winch) may be actuated by an external actuator. A torque provided by the external actuator may be amplified by the differential planetary gear transmission. A torque limiter may be included to ensure that torque provided to the winch assembly does not exceed a threshold. Further, a likelihood of mechanical degradation due to torque overload may be reduced. The pulling tool assembly may be operated as a handheld device. Alternatively, the pulling tool assembly may be hooked or attached to an external support, when desired, via the plurality of tie rods. 
     Note that the example control and estimation routines included herein can be used with various engine and/or vehicle system configurations. The control methods and routines disclosed herein may be stored as executable instructions in non-transitory memory. The specific routines described herein may represent one or more of any number of processing strategies such as event-driven, interrupt-driven, multi-tasking, multi-threading, and the like. As such, various actions, operations, and/or functions illustrated may be performed in the sequence illustrated, in parallel, or in some cases omitted. Likewise, the order of processing is not necessarily required to achieve the features and advantages of the example embodiments described herein, but is provided for ease of illustration and description. One or more of the illustrated actions, operations and/or functions may be repeatedly performed depending on the particular strategy being used. Further, the described actions, operations and/or functions may graphically represent code to be programmed into non-transitory memory of the computer readable storage medium in the engine control system. 
     The following claims particularly point out certain combinations and sub-combinations regarded as novel and non-obvious. These claims may refer to “an” element or “a first” element or the equivalent thereof. Such claims should be understood to include incorporation of one or more such elements, neither requiring nor excluding two or more such elements. Other combinations and sub-combinations of the disclosed features, functions, elements, and/or properties may be claimed through amendment of the present claims or through presentation of new claims in this or a related application. Such claims, whether broader, narrower, equal, or different in scope to the original claims, also are regarded as included within the subject matter of the present disclosure.