Patent Publication Number: US-2023138617-A1

Title: Automated footwear lacing systems, devices, and techniques

Description:
PRIORITY APPLICATIONS 
     This application is a divisional application of U.S. patent application Ser. No. 15/8993,914, filed May 31, 2018, which application claims the benefit of priority to U.S. Provisional Patent Application Ser. No. 62/513,213, filed May 31, 2017, the contents of which are incorporated by reference herein in their entireties. 
    
    
     FIELD OF THE INVENTION 
     The following specification describes various aspects of a footwear assembly involving a lacing system including a motorized or non-motorized lacing engine, footwear components related to the lacing engines, automated lacing footwear platforms, and related concepts. More specifically, much of the following specification describes various aspects of lacing engine architectures (configurations) for use in footwear including motorized or non-motorized automated lace tightening. The specification also discusses related concepts, such as battery charging devices, storage and delivery packaging, as well as footwear user interfaces. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the drawings, which are not necessarily drawn to scale, like numerals may describe similar components in different views. Like numerals having different letter suffixes may represent different instances of similar components. The drawings illustrate generally, by way of example, but not by way of limitation, various embodiments discussed in the present document. 
         FIG.  1    is an exploded view illustration of components of a portion of a footwear assembly with a motorized lacing system, according to some example embodiments. 
         FIG.  2    is a perspective view of an example lacing engine, according to some example embodiments. 
         FIG.  3 A  is an isometric view of an example lacing engine, according to some example embodiments. 
         FIG.  3 B  is a top view of an example lacing engine, according to some example embodiments. 
         FIG.  3 C  is a cross-sectional side view across section A-A of  FIG.  3 B  of an example lacing engine, according to some example embodiments. 
         FIG.  3 D  is an exploded isometric view of an example lacing engine, according to some example embodiments. 
         FIG.  4 A  is an isometric view of an example lacing engine, according to some example embodiments. 
         FIG.  4 B  is a top view of an example lacing engine, according to some example embodiments. 
         FIG.  4 C  is a cross-sectional side view across section A-A of  FIG.  4 B  of an example lacing engine, according to some example embodiments. 
         FIG.  4 D  is a cross-sectional side view across section A-A of  FIG.  4 B  of an example lacing engine, according to some example embodiments. 
     
    
    
     Any headings provided herein are merely for convenience and do not necessarily affect the scope or meaning of the terms used or discussion under the heading. 
     DETAILED DESCRIPTION 
     The concept of self-tightening shoe laces was first widely popularized by the fictitious power-laced Nike® sneakers worn by Marty McFly in the movie Back to the Future II, which was released back in 1989. While Nike® has since released at least one version of power-laced sneakers similar in appearance to the movie prop version from Back to the Future II, the internal mechanical systems and surrounding footwear platform employed do not necessarily lend themselves to mass production and/or daily use. Additionally, other previous designs for motorized lacing systems comparatively suffered from problems such as high cost of manufacture, complexity, assembly challenges, and poor serviceability. The present inventors have developed various concepts to deliver a modular footwear platform to accommodate motorized and non-motorized lacing engines that solves some or all of the problems discussed above, among others. In order to fully leverage the modular lacing engine discussed briefly below and in greater detail in co-pending application Ser. No. 15/450,860, titled “LACING APPARATUS FOR AUTOMATED FOORWEAR PLATFORM,” the present inventors developed various alternative and complementary lacing engine designs, battery chargers, user interface concepts, and display/carrying cases discussed herein. 
     The motorized lacing engine discussed below in reference to  FIG.  1   , as well as alternative concepts discussed throughout, was developed from the ground up to provide a robust, serviceable, and inter-changeable component of an automated lacing footwear platform. The lacing engine includes unique design elements that enable retail-level final assembly into a modular footwear platform. The lacing engine design allows for the majority of the footwear assembly process to leverage known assembly technologies, with unique adaptions to standard assembly processes still being able to leverage current assembly resources. 
     In an example, the modular automated lacing footwear platform includes a mid-sole plate secured to the mid-sole for receiving a lacing engine. The design of the mid-sole plate allows a lacing engine to be dropped into the footwear platform as late as at a point of purchase. The mid-sole plate, and other aspects of the modular automated footwear platform, allow for different types of lacing engines to be used interchangeably. For example, the motorized lacing engine discussed below could be changed out for a human-powered lacing engine. Alternatively, a fully automatic motorized lacing engine with foot presence sensing or other optional features could be accommodated within the standard mid-sole plate. 
     Utilizing motorized or non-motorized centralized lacing engines to tighten athletic footwear presents some challenges in providing sufficient performance without sacrificing some amount of comfort. Lacing architectures discussed herein have been designed specifically for use with centralized lacing engines and are designed to enable various footwear designs from casual to high-performance. 
     This initial overview is intended to introduce the subject matter of the present patent application. It is not intended to provide an exclusive or exhaustive explanation of the various inventions disclosed in the following more detailed description. 
     Automated Footwear Platform 
     The following discusses various components of the automated footwear platform including a motorized lacing engine, a mid-sole plate, and various other components of the platform. While much of this disclosure focuses on lacing architectures for use with a motorized lacing engine, the discussed designs are applicable to a human-powered lacing engine or other motorized lacing engines with additional or fewer capabilities. Accordingly, the term “automated” as used in “automated footwear platform” is not intended to only cover a system that operates without user input. Rather, the term “automated footwear platform” includes various electrically powered and human-power, automatically activated and human activated mechanisms for tightening a lacing or retention system of the footwear. 
       FIG.  1    is an exploded view illustration of components of a motorized lacing system for footwear, according to some example embodiments. The motorized lacing system  1  illustrated in  FIG.  1    includes a lacing engine  10 , a lid  20 , an actuator  30 , a mid-sole plate  40 , a mid-sole  50 , and an outsole  60 .  FIG.  1    illustrates the basic assembly sequence of components of an automated lacing footwear platform. The motorized lacing system  1  starts with the mid-sole plate  40  being secured within the mid-sole. Next, the actuator  30  is inserted into an opening in the lateral side of the mid-sole plate opposite to interface buttons that can be embedded in the outsole  60 . Next, the lacing engine  10  is dropped into the mid-sole plate  40 . In an example, the lacing system  1  is inserted under a continuous loop of lacing cable and the lacing cable is aligned with a spool in the lacing engine  10  (discussed below). Finally, the lid  20  is inserted into grooves in the mid-sole plate  40 , secured into a closed position, and latched into a recess in the mid-sole plate  40 . The lid  20  can capture the lacing engine  10  and can assist in maintaining alignment of a lacing cable during operation. 
     In an example, the footwear article or the motorized lacing system  1  includes or is configured to interface with one or more sensors that can monitor or determine a foot presence characteristic. Based on information from one or more foot presence sensors, the footwear including the motorized lacing system  1  can be configured to perform various functions. For example, a foot presence sensor can be configured to provide binary information about whether a foot is present or not present in the footwear. If a binary signal from the foot presence sensor indicates that a foot is present, then the motorized lacing system  1  can be activated, such as to automatically tighten or relax (i.e., loosen) a footwear lacing cable. In an example, the footwear article includes a processor circuit that can receive or interpret signals from a foot presence sensor. The processor circuit can optionally be embedded in or with the lacing engine  10 , such as in a sole of the footwear article. 
       FIG.  2    is an illustration of various internal components of lacing engine  10 , according to example embodiments.  FIG.  2    also illustrates how a load cell can be incorporated into a lacing engine, such as lacing engine  10 . In this example, the lacing engine  10  further includes spool magnet  136 , O-ring seal  138 , worm drive  140 , bushing  141 , worm drive key  142 , gear box  144 , gear motor  145 , motor encoder  146 , motor circuit board  147 , worm gear  150 , circuit board  160 , motor header  161 , battery connection  162 , and wired charging header  163 . The spool magnet  136  assists in tracking movement of the spool  130  though detection by a magnetometer (not shown in  FIG.  2 C ). The o-ring seal  138  functions to seal out dirt and moisture that could migrate into the lacing engine  10  around the spool shaft  133 . In this example, the load cell can be incorporated outboard of bushing  141  to detect forces transmitted from the spool  130  through the worm gear  150  onto the worm drive  140 . Information from the load cell can be used as an input to the tension control to tighten or loosen lace tension based on an inference on activity level being experienced by the footwear. For example, if the load cell is detecting frequent shock loading on the laces, it can be inferred that activity level of high (e.g., engaged in basketball game). Alternatively, if the load cell is detecting little or no shock loading, then the lacing engine can infer low activity level and potentially loosen the laces. 
     In this example, major drive components of the lacing engine  10  include worm drive  140 , worm gear  150 , gear motor  145  and gear box  144 . The worm gear  150  is designed to inhibit back driving of worm drive  140  and gear motor  145 , which means the major input forces coming in from the lacing cable via the spool  130  are resolved on the comparatively large worm gear and worm drive teeth. This arrangement protects the gear box  144  from needing to include gears of sufficient strength to withstand both the dynamic loading from active use of the footwear platform or tightening loading from tightening the lacing system. The worm drive  140  includes additional features to assist in protecting the more fragile portions of the drive system, such as the worm drive key  142 . In this example, the worm drive key  142  is a radial slot in the motor end of the worm drive  140  that interfaces with a pin through the drive shaft coming out of the gear box  144 . This arrangement prevents the worm drive  140  from imparting any axial forces on the gear box  144  or gear motor  145  by allowing the worm drive  140  to move freely in an axial direction (away from the gear box  144 ) transferring those axial loads onto bushing  141  and the housing structure  100 . As noted above, the arrangement also allows for convenience placement of a load cell outboard of the bushing  141  to measure axial forces on the drive training from laces. 
     Planetary Gear Train Lacing Engine 
       FIG.  3 A  is an isometric view of lacing engine  200 , according to some example embodiments.  FIG.  3 B  is a top view of lacing engine  200 , according to some example embodiments.  FIG.  3 C  is a cross-sectional side view across section A-A of  FIG.  3 B  of lacing engine  200 , according to some example embodiments.  FIG.  3 D  is an exploded isometric view of lacing engine  200 , according to some example embodiments.  FIGS.  3 A- 3 D  are discussed below concurrently. 
       FIGS.  3 A- 3 D  are diagrams illustrating a planetary gear based lacing engine, according to some example embodiments. In this example, the planetary gear based lacing engine  200  can include a housing  205  (including a base  206  and a lid  208 ), a motor  210  (including a shaft  212 ), a worm drive  215 , a sun gear bearing  216 , fasteners  217 , a sun gear  220  (including outer teeth  221  and inner teeth  222 ), a stationary ring gear  225  (including flanges  226 ), a rotating ring gear  230 , a pin  235 , a pair of plates  250 , planet gears  255 A- 255 C (not shown in  FIGS.  3 A and  3 B  and only two visible in  FIG.  3 C ), a second planet gear  255 B, a spool  260 , a ring gear bearing  265 , a printed circuit board (PCB)  270 , a battery  275 , a charge coil  280 , and a thrust bearing  285 . Also shown in  FIG.  3 B  are section markers A-A. Also shown in  FIG.  3 C  are central axis A and orientation indicators Top and Bottom. 
     In this example, a planetary gear system can be driven by the worm gear of the shaft interfacing with the sun gear to drive the spool. The planetary gear system can provide a compact (dense) and high-ratio package (large gear reduction). The example design can balance radial forces and allow primarily torsional stresses on components. Any of the previously discussed lacing engines can be modified to include a planetary gear drive train. The details of this example are discussed further below. 
     The housing  205  can be a rigid or semi-rigid body comprised of materials such as metals, plastics, foams, elastomers, ceramics, composites, and combinations thereof. The housing  205  can include the base  206  sized and shaped to receive the drive train (the motor  210 , the gears, the bearings, etc.), the PCB  270 , the battery  275 , and the charge coil  280  therein. The base  206  can include a recess  207  at a bottom of the base  206 . The lid  208  can be sized and shaped to be received on and partially in the body  206  to enclose the components within the base  206 . 
     The motor  210  can be an electric motor, in one example, electrically powered by the battery  275  to provide rotational output through the shaft  212 . The worm drive  215  can be secured to the shaft  212  and can be rotatable therewith. In some examples, the shaft  212  can be a worm gear and in some examples, the worm drive  215  can be releasably or fixedly coupled to the shaft  212 . 
     Fasteners  217  can be fasteners of many kinds such as screws, rivets, pins, nails, and the like. In other examples, fasteners  217  can be replaced with other means of fastening such as adhesives, welding, snap-fit, and the like. 
     Each of the sun gear  220 , the rotating ring gear  230 , and the planet gears  255 A- 255 C can be gears. That is, each of the sun gear  220 , the rotating ring gear  230 , and the planet gears  255 A- 255 C can be rigid or semi-rigid members each rotatable about an axis and each configured to engage another member to transfer torque and therefore rotation. Each of these gears can include teeth that can be spur, bevel, worm, helical, or the like. 
     The sun gear  220  can include outer teeth  221  and inner teeth  222 . The sun gear  220  can rotate relative to the housing  205  on the sun gear bearing  216  where the sun gear bearing  216 , and in some examples part of the sun gear  220 , can be located in the recess  207  of the base  206  of the housing  205  where the sun gear  220  can rotate thereabout. 
     In some examples, the sun gear  220  can be a worm wheel. That is, the sun gear  220  can include an outer flange having a height relatively larger than that of the central hub or central gear portion, thus striking a resemblance to a wheel. In some examples, the outer teeth  221  of the worm wheel can be of a worm-type and can be configured to engage the worm drive  215  of the shaft  212  and can receive rotation and torque therefrom. The inner teeth  222  can extend radially outward from a center portion or hub of the sun gear having a substantially smaller diameter than the outer portion or outer flange that includes the outer teeth  221 . In this way, the sun gear  220  can provide a relatively large gear ratio or gear reduction. 
     The planet gears  255 A- 255 C can be relatively small gears configured to interface with the inner teeth  222  of the sun gear while rotating about the central axis A of the sun gear. Together, the planet gears  255 A- 255 C can transfer rotation and torque to the rotating ring gear  230 . The planet gears  255 A- 255 C can be held together by the pair of plates  250 . In some examples, each of the planet gears  255 A- 255 C can receive the pin  235  therethrough, where each of the pins  235  can be secured to the plates  250  on both sides of each of the planet gears  255 A- 255 C to help fix relative positions of the planet gears  255 A- 255 C while still allowing the planet gears  255 A- 255 C to rotate about their respective pins  235 . The thrust bearing  285  can engage the sun gear  220  and one of the plates  250  to space the plates  250  and the planet gears  255 A- 255 C relative to the sun gear  220 . Though three of planet gears  255 A- 255 C are discussed and shown, fewer or more planet gears can be used in lacing engine  200 . For example, 1, 2, 4, 5, 6, 7, 8, 9, 10, or the like planet gears can be used. 
     The rotating ring gear  230  can be a single gear coaxial with the central axis A and configured to engage each of the planet gears  255 A- 255 C. The rotating ring gear  230  can be disposed within the stationary ring gear  225  and can be rotatable within and relative to the stationary ring gear  225 . The rotating ring gear  230  can be coupled to the spool  260  at a substantially central portion of the rotating ring gear  230 . In other examples, the spool  260  can be connected to other portions of the rotating ring gear  230 . The spool  260  can be a bobbin, reel, or cylinder configured to wind and retain a portion of a lace of a footwear article. In some examples, the spool  260  can be connected to the rotating ring  230  to be rotated therewith. The spool  260  can be replaced with a lace spool similar to lace spool  130 , or an alternative design that meets the lace take-up requirements of the lacing engine design. 
     The stationary ring gear  225  can be a stationary gear insertable into the base  206  of the housing  205 . In some examples, the stationary ring gear  225  can extend from the top of the base  206  toward the bottom and can engage the planet gears  255 A- 255 C, where the planet gears  255 A- 255 C each engage inner teeth of the stationary ring gear  225  and to rotate about a central portion of the sun gear  220 . In some examples, the stationary ring gear  225  can extend toward the bottom to engage the sun gear  220  or a bearing separating the sun gear  220  and the stationary ring gear  225  to allow relative rotation therebetween. 
     The stationary ring gear  225  can include a plurality of flanges  226 , where each of the flanges  226  extends radially outward toward a periphery of the lid  208 . Each flange  226  can be configured to receive a fastener therethrough, such as one of fasteners  217  to secure the stationary ring gear to the lid  208  and to the base  206 . The flanges  226  can be placed for stability while balancing volumetric optimization of the other components within the housing  205 . 
     The ring gear bearing  265  can be a bearing configured to engage the rotating ring gear and the lid  208  to retain the ring gear  230  (and other components) within the base  206  of the housing  205  and to allow rotation of the ring gear  230  relative to the housing  205 . 
     The printed circuit board (PCB)  270  can be an integrated circuit board configured to support and electrically connect components, including transistors and circuits of any of multiple forms known in the industry, and can be configured to provide conductive structures and contacts to distribute signals. In some examples, the PCB  270  can be a programmable controller, such as a single or multi-board computer, or a direct digital controller (DDC). In other examples, the PCB  270  can be any relatively small computing device including a processor with or without wireless communication capabilities. 
     The battery  275  can be configured to store power received from charge coil  280 , which can be distributed to thereafter to the PCB  270  and motor  210 . In some examples, battery  275  can be a replaceable battery, and the like. The charge coil  280  can be, in some examples, an inductive charging coil configured to interact with an inductive charger to supply the battery  275  with an electric charge for storage and/or use. 
     In operation of some examples, the battery  275  can be charged by the charge coil  280 . When a lacing event is called for, the PCB  270  can transfer (or can instruct the battery to transfer) power to the motor  210  to rotate the shaft  212 . When the shaft  212  rotates, so too does the worm drive  215 . Because the worm drive  215  interfaces with the sun gear (or worm wheel)  220  (specifically outer teeth  221  of the sun gear  220 ), rotation of the worm drive  215  drives rotation of the sun gear  220  about the central axis A. 
     The sun gear  220 , being engaged with each of planet gears  255 A- 255 C via inner teeth  222 , can transfer rotation to each of planet gears  255 A- 255 C to cause each of planet gears  255 A- 255 C to rotate about a central portion or hub of the sun gear  220 . The planet gears  255 A- 255 C can transfer the rotation further to the rotating ring gear  230  and the spool  260  to drive winding of a lace during the lacing event. Such rotation of the spool  260  can continue until the PCB  270  issues a command to stop rotation of the shaft  212 , which stops rotation of the sun gear, the planet gears  255 A- 255 C, the rotating ring gear  230 , and the spool  260 . A position of the spool  260  can be held after a lacing event, for example during use of the footwear article until a loosening event occurs. In some examples, the position of the spool  260  can be held because an interface between the worm drive  215  and the outer teeth  220  of the worm wheel cannot operate in a reverse direction of rotation, thus acting as a mechanical lock for retention of tension dynamics without an additional mechanism for this purpose, which can help save cost and reduce complexity of the lacing engine  200 . 
     Because, at least in part, of the nesting of the gears (such as the planet gears  255 A- 255 C within the sun gear  220 ), the planetary gear system of the lacing engine  200  can provide a compact (dense) lacing engine for a footwear article that is resilient and reliable. Though the lacing engine  200  is relatively small, the planetary gear system can help to offer a high-ratio package (large gear reduction) drivetrain to help obtain a desired lacing speed and torque. 
     Further, because multiple planet gears, such as the three planet gears  255 A- 255 C, are used within lacing engine  200 , the load can distributed between three parts. This can be important because the planet gears  255 A- 255 C can be the smallest and/or most breakable parts of the lacing engine  200 . Therefore, by dividing the load, failure of the planet gears  255 A- 255 C can be reduced. 
     By positioning rotating ring gear  230  near a top of the lacing engine (and therefore away from a bottom of the footwear article), mounting of the ring gear  230  through the base  206  can be easier and impact to the rotating ring gear  230  and the spool  260  due to user-caused housing deflection can be reduced. For example, point-loading to the housing  206  can be caused by rock or stone strikes to the housing  206  during use. These strikes are most likely to occur on the bottom of the housing  206 , away from the spool  260  and the rotating ring gear  230 . Also, a large portion of the mounting interface of the lacing engine (such as stationary ring gear  225  and its flanges  226 ) occurs at a top portion of the housing, away from the stresses and forces of deflection events discussed above. Further, because the sun gear bearing  216  mounts to sun gear  220  at recess  207  in a single bearing mount point in the bottom of base  206  of housing  205 , the drive train can be substantially isolated from deflection of the housing  205 . 
     Also, because of the relative positioning of the sun gear  220 , the worm drive  215 , and the PCB  270 , a motor encoder (such as the motor encoder  146 ) can be easily integrated and positioned within the housing to provide proper and low latency control feedback of the motor  210 , which can improve operation of the lacing engine  200 . 
     This example design of the lacing engine  200  can balance delivery of radial forces and speed reduction and helping to allow primarily torsional stresses on components while still providing a relatively low lacing time using a planetary gear train that can provide good rotational stiffness and can distribute load among planets and ring gears. 
     Power Spring Lacing Engine 
       FIG.  4 A  is an isometric view of lacing engine  400 , according to some example embodiments.  FIG.  4 B  is a top view of lacing engine  400 , according to some example embodiments.  FIG.  4 C  is a cross-sectional side view across section A-A of  FIG.  4 B  of lacing engine  400 , according to some example embodiments. 
       FIGS.  4 A- 4 C  are diagrams illustrating a power spring based lacing engine, according to some example embodiments. In this example, the power spring based lacing engine  400  can include a housing  405  (including a base  406  and a lid  408 ), a motor  410  a shaft  415 , a spring arbor  420 , a power spring  430 , a clutch  435 , a stem  440 , a coupler (spool arbor)  445 , a coupler bearing  450 , a spool  460 , a driven gear  465 , a driving gear  470 , a spring arbor bearing  475 , and a driven gear bearing  480 . Also shown in  FIG.  4 B  are section markers A-A and shaft axis S. Also shown in  FIG.  4 C  are central axis A, transverse axis T, and orientation indicators Top and Bottom. In some examples, lacing engine  400  can also include a printed circuit board (PCB), a battery, and a charge coil. 
     In this example, a power spring lacing engine can be driven by the motor to rotate the power spring to store energy in the power spring. The power spring can selectably and controllably release stored energy to the coupler to rotate the spool during a lacing event and the power spring can be rotated to store energy between lacing events. The power spring system can use a low quantity of small parts to provide a compact, quiet, and cost-effective lacing engine. Any of the previously discussed lacing engines can be modified to include a power spring drive train. The details of this example are discussed in further detail below. Accordingly, alternative lace spool designs can be incorporated into the lacing engine  400  discussed below. 
     The housing  405  can be a rigid or semi-rigid body comprised of materials such as metals, plastics, foams, elastomers, ceramics, composites, and combinations thereof. The housing  405  can include the base  406  sized and shaped to receive the drive train (the motor  410 , the gears, the bearings, the spring, etc.), the PCB, the battery, and the charge coil therein. The base  406  can include recesses at a bottom of the base  406  to receive bearings  475  and  480  therein. The lid  408  can be sized and shaped to be received on and partially in the body  406  to enclose the components within the base  406 . 
     The motor  410  can be an electric motor, in one example, electrically powered by the battery to provide rotational output through the shaft  415 . The shaft  415  can be releasably or fixedly coupled to the driving gear  470 , which can be engaged with the driven gear  465 . In some examples, each of the driven gear  465  and the driving gear  470  can be conical gears, or gears having a geometric shape substantially of a cone. 
     In some examples, the driven gear  465  and the driving gear  470  can be conical gears, such as bevel gears. For example, the driving gear can rotate about the drive axis S and the driven gear can rotate about the transverse axis T, which can be substantially transverse to the drive axis S and substantially parallel to the central axis A. In this example, the driving gear  470  can be rotated by the shaft  415  of the motor  410  to rotate the driven gear  465  about the transverse axis T. In some examples, the driven gear  465  can be supported by and rotatable relative to the driven gear bearing  480 , where the driven gear bearing  480  can be secured to the bottom of the housing  405 , in some examples. 
     The spring arbor  420  can be a rotating arbor, coupler, chuck, or the like. The spring arbor  420  can be supported by the spring arbor bearing  475 , which can be secured to the bottom of the housing  405 , in some examples. In some examples, the spring arbor bearing  475  and the driven gear bearing  480  can be journal bearings, ball bearings, needle bearings, or the like. The stem  440  can be a rigid body secured to the power spring  430  and secured to the clutch  435 . In some examples, the stem  440  can be supported by the spring arbor  420  and rotatable relative thereto. In some examples, the spring arbor  420  can controllably engage and disengage the driven gear  465  to selectively transfer torque to the power spring  430  from the motor  410 , as discussed below in further detail. 
     The power spring  430  can be a biasing or resilient element configured to store potential energy. The power spring  430  can be made of materials such as metals, polymers, or the like. In some examples, the power spring  430  can be made of spring steel. In some examples, the power spring  430  can be a coil spring, a torsion spring, a wound spring, or the like. The power spring  430  can be supported and connected to the spring arbor  420 , where the spring arbor can be engaged with the driven gear  465  to rotate the spring arbor  420  and therefore the power spring  430 . 
     The clutch  435  can be a mechanical or electromechanical clutch configured to selectively transfer rotation therethrough. In an example where the clutch  435  is electromechanical, the clutch  435  can transfer rotation (and torque) in response to a control signal from the PCB. In some examples, the clutch  435  can be a ratcheting clutch to help limit reverse rotation of the stem  440  (and therefore of the power spring  430 ). 
     The coupler (spool arbor)  445  can be a rotating arbor, coupler, chuck, or the like. The coupler  445  can, in some examples, be coupled to the spool  460  and the clutch and can be engaged with the coupler bearing  450 . In some examples, the coupler  445  can be configured to selectively couple to the spool  460 . In some examples, when the spool  460  is connected to the coupler (spool arbor)  445 , the spool  460  can be rotated therewith. The coupler bearing  450  can be a bearing secured to the lid  408  of the housing. The coupler bearing  450  can be engaged with the coupler  445  to help limit non-rotational moving of the coupler  445  (and therefore of the clutch  435  and the stem  460 ). The spool  460  can be a bobbin, reel, or cylinder configured to wind and retain a portion of a lace of a footwear article. 
     In general operation of some examples, the battery can be charged by the charge coil, which can be controlled by the PCB to transfer power to the motor  410  to rotate the shaft  415 . When the shaft  415  rotates, so too does the driving gear  470 . Because the driving gear  470  interfaces with the driven gear  465 , the driving gear  470  drives the driven gear  465  to rotate about the transverse axis T. 
     Rotation of the driven gear  465  can drive rotation of the spring arbor  420  about the central axis A. Because the spring arbor  420  can be secured to the drive spring  430 , rotation of the spring arbor  420  can wind the drive spring  430  (and the stem  440 ). When the drive spring  430  is un-coupled from the spool  460 , the drive spring  430  can store mechanical (and rotational) potential energy therein. When a lacing event is called for, the PCB can send a signal to the clutch to couple the stem  440  to the spool  460  to transfer rotation from the power spring  430 , through the stem  440 , to the coupler  445 , and to the spool  460  to drive winding of a lace during the lacing event. Such rotation of the spool  460  can continue until the PCB issues a command to stop rotation of the spool  460 , which can, in some examples, disengage the clutch (disengage the stem  440  from the spool), or in other examples, hold a position of the spool  460  and the power spring  430 . During use of the footwear article, the position of the spool  460  can be held until a loosening event occurs. 
     The lacing engine  400  can also operate in various stages of lacing. In some examples, the clutch  435  allows for the power spring and the spool  460  to operate independently. For example, the spool  460  can be coupled and uncoupled by the coupler  445  and the spring  430  can be coupled and uncoupled to the motor  410  by the spring arbor  420 . For example, when the lace is loose, the power spring  430  can be loaded where the spool  460  is held in place and is not coupled to the power spring  430  while the spring arbor  420  engages the driven gear  365  while the power spring  430  is wound or tightened by the motor  410 . After winding of the power spring  430 , the spool  460  can be coupled to the power spring  430  (via the clutch  435  and the stem  440 ) and the spool  460  can be held in place by the coupler  445  as the spring arbor  420  can be held in place by the driven gear  465 . When a foot is detected in the footwear article or otherwise during a lacing event, the spool  460  can be coupled to the power spring  430  and the power spring  430  can be released from the motor  410  by the spring arbor  420  to allow the power spring  430  to rotate the spool  460  to tighten the lace. 
     Also, during an adjustment of increased lace tension, the power spring  430  can be first loaded by decoupling the spool  460  from the power spring  430  and holding the spool  460  in place with the coupler  445  while the power spring  430  is coupled to the motor  410  via the spring arbor  420  engaging the driven gear  465  so that the motor  410  can wind the power spring  430 . In some examples, winding can be skipped during an adjustment. In either case, when the power spring  430  is wound, the spool  460  can be coupled to the power spring  430  and the power spring  430  can be released from the motor  410  and the spool  460  can be released from the coupler  445  to transfer torque from the power spring  430  to the spool  460  to tighten the lace. When an adjustment command to loosen the lace occurs, the spool  460  can remain coupled to the power spring and the lace can be manually loosened. 
     During wearing of the footwear article and when the lace is to be held tight, the spool  460  can be held (by the coupler  445 ) while the spool  460  is coupled to the power spring  430  by the clutch  435  and while the spring arbor  420  is engaged with the driven gear  465  to prevent loosening. When a loosen event occurs the spool  460  can be released and the power spring  430  can be released. 
     In some examples, the stem  440  can include an additional clutch to be selectively couple the stem  440  to the power spring  430 . In other examples, the coupler  445  can include a clutch or clutching mechanism to selectively couple the coupler  445  to the spool  460 . In one example, the clutch of the coupler  445  can be released during a loosening event to allow the spool to spin freely so that the lace can be loosened. 
     In some examples, the clutch  435  can include a mechanism for reversing a rotational direction of the coupler  445  and therefore of the spool  460  to selectively transmit rotation provided by the power spring  430  in either rotational direction to the spool  460 . This can allow the power spring  430  to drive the spool  460  to selectively tighten or loosen the lace. In other examples, the clutch  435  can include a mechanism to allow winding of the spring  430  through the spool  460  via the stem  440  such that a manual unlacing event can wind the spring, which can further increase time between charges and/or can decrease a size of the battery. 
     In some examples, the power spring  430  can be sized to power multiple lacing events. For example, the power spring  430  can be sized to power  2 ,  5 ,  10 ,  15 ,  20 , or the like lacing events. Because the lacing engine  400  provides an ability to store potential mechanical energy for one or more lacing events, the lacing engine  400  can store additional power for lacing events beyond the electrical power capacity of the battery by winding the power spring  430  and fully charging the battery. Also, in some examples, where the power spring  430  can store enough mechanical power for multiple lacing events, a battery may be eliminated from the lacing engine, saving materials and cost. 
     Because the power spring  430  can power the lacing even without the use of the motor  410 , the lacing event can be relatively quiet. Also, because the power spring  430  can be wound outside of a lacing event (i.e. before the lacing event), the motor can be operated more efficiently (e.g. at a lower speed for a longer period of time) to help reduce consumption of power. 
     In some examples, the coupler  445  can be configured to operate as a clutch to selectively provide torque from the power spring  430  to the spool  460 . In these examples, the coupler  445  can couple to one or more of the stem  440  and to the spool  460 , and can uncouple from one or more of the stem  440  and to the spool  460  to allow for individual rotation of both. 
       FIG.  4 D  is a cross-sectional side view across section A-A of  FIG.  4 B  of lacing engine  400 , according to some example embodiments. The components of the lacing engine  400  of  FIG.  4 D  can be consistent with those of  FIGS.  4 A- 4 C  discussed above, where  FIG.  4 D  further shows a path for transfer of rotational energy (torque) from the driven gear to the lace. 
     In the example shown in  FIG.  4 D , torque can be transferred from the drive train, for example, from the motor  410  through the driven gear  465  to the spring arbor  420  at connection  505  with a speed reduction. The spring arbor  420  can transfer torque through the power spring  435  to the stem  440  and directly at connections  510  to the clutch  435  (when the clutch  435  is engaged), the coupler  445 , and to the spool  460 . In some examples, when the power spring  430  is fully wound, this transfer of torque can be direct. In other examples, this transfer can be delayed by winding of the power spring  430 . The overall power (torque) transfer path  500  is illustrated in  FIG.  4 D . 
     EXAMPLES 
     The following, non-limiting examples, detail certain aspects of the present subject matter to solve the challenges and provide the benefits discussed herein, among others. 
     Example 1 is a lacing engine for an automated footwear platform, the lacing engine comprising: a housing securable within a footwear article; and a drivetrain located at least partially within the housing, the drivetrain comprising: a motor including a shaft rotatable within the housing; a sun gear driven by the shaft to rotate about a central axis of the sun gear; a planet gear engaged with and driven to rotate by the sun gear; a rotating ring gear engaged with and driven by the planetary gear to rotate about the central axis; and a spool secured to the ring gear and rotatable therewith, the spool configured to control a lace of the footwear article and to wind the lace as the ring gear rotates in a first direction. 
     In Example 2, the subject matter of Example 1 optionally includes wherein the sun gear includes: an outer set of teeth engaged with the shaft and driven thereby; and an inner set of teeth driven to rotate coaxially with the outer set of teeth, the planetary gear engaged with and driven by the inner set of teeth. 
     In Example 3, the subject matter of any one or more of Examples 1-2 optionally include a plurality of planetary gears including the planet gear, each planetary gear of the plurality of planetary gears engageable with and driven by the inner set of teeth. 
     In Example 4, the subject matter of any one or more of Examples 2-3 optionally include wherein the sun gear comprises a worm wheel. 
     In Example 5, the subject matter of Example 4 optionally includes wherein the plurality of planetary gears are located within the worm wheel. 
     In Example 6, the subject matter of any one or more of Examples 2-5 optionally include wherein the shaft includes a worm drive engageable with the outer set of teeth of the worm wheel to rotate the sun gear in response to rotation from the motor. 
     In Example 7, the subject matter of any one or more of Examples 1-6 optionally include a ring gear bearing engaged with the ring gear. 
     In Example 8, the subject matter of Example 7 optionally includes wherein the housing further comprises a lid securable to a base of the housing, the lid engageable with the ring gear bearing to axially retain the ring gear and the ring gear bearing within the housing. 
     In Example 9, the subject matter of Example 8 optionally includes a stationary ring gear, the rotating ring gear disposable within the stationary ring gear and rotatable relative to the stationary ring gear, the lid securable to the stationary ring gear to limit movement of the stationary ring gear relative to the housing, and the stationary ring gear engageable with the sun gear to limit axial movement of the sun gear relative to the housing. 
     In Example 10, the subject matter of Example 9 optionally includes wherein the stationary ring gear includes a plurality of mounting flanges securable to the lid, each flange extending radially outward from a body of the stationary ring gear, each of the flange configured to receive a fastener to secure the stationary ring gear to the lid. 
     In Example 11, the subject matter of any one or more of Examples 1-10 optionally include a pair of plates surrounding the planet gear; and a pin extending through the planet gear and the pair of plates to retain the planet gear between the pair of plates, the planet gear rotatable about the pin. 
     In Example 12, the subject matter of Example 11 optionally includes a thrust bearing engaged with one plate of the pair of plates and with a first side of the sun gear. 
     In Example 13, the subject matter of Example 12 optionally includes wherein the housing includes a recess configured to receive at least a portion of the sun gear therein. 
     In Example 14, the subject matter of Example 13 optionally includes a sun gear bearing at least partially disposable in the recess of the housing, the bearing engageable with a second side of the sun gear. 
     Example 15 is a lacing engine for an automated footwear platform, the lacing engine comprising: a housing securable within a footwear article; and a drivetrain located at least partially within the housing, the drivetrain comprising: a motor including a shaft rotatable within the housing; a power spring driven by the shaft to rotate about a central axis to deliver stored energy upon activation; a spool rotatable about the central axis, the spool configured to controllably wind a lace of the footwear article; and a clutch configured to controllably couple the power spring to the spool to transfer rotation therebetween. 
     In Example 16, the subject matter of Example 15 optionally includes wherein the clutch is a ratcheting clutch. 
     In Example 17, the subject matter of any one or more of Examples 15-16 optionally include a spring arbor connected to the housing and rotatable relative thereto, the spring arbor supporting the power spring, and the spring arbor controllably coupled to the shaft to transfer rotation from the shaft to the power spring. 
     In Example 18, the subject matter of Example 17 optionally includes a conical driving gear secured to the shaft and rotatable with the shaft about a shaft axis; and a conical driven gear engaged with the conical driving gear and driven to rotate thereby about a transverse axis substantially transverse to the shaft axis, the conical driven gear coupled to the spring arbor to transfer rotation thereto. 
     In Example 19, the subject matter of any one or more of Examples 15-18 optionally include wherein the power spring is one of a coil spring or a torsion spring. 
     In Example 20, the subject matter of any one or more of Examples 15-19 optionally include a spool arbor positioned at least partially within the housing and coaxially with the power spring, the spool arbor controllably coupled to the spool and coupled to the clutch, the spool arbor rotatable about the central axis. 
     In Example 21, the subject matter of any one or more of Examples 15-20 optionally include a stem supported by the spool arbor and coupled to the power spring and to the clutch, the stem configured to be driven by the power spring to rotate relative to the spool arbor. 
     In Example 22, the subject matter of Example 21 optionally includes a coupler bearing secured to the housing and engaged with the spool arbor limit movement of the spool, the spool arbor, the clutch, and the power spring relative to the housing. 
     In Example 23, the subject matter of any one or more of Examples 15-22 optionally include wherein the motor is configured to rotate the shaft to drive the power spring to store rotational energy therein, the power spring configured to transfer the rotational energy through the clutch to the spool to wind the lace when the clutch selectively connects the power spring to the spool. 
     In Example 24, the subject matter of any one or more of Examples 15-23 optionally include wherein the clutch is positioned coaxially with the power spring, 
     In Example 25, the system, device, or method of any one of or any combination of Examples 1-23 is optionally configured such that all elements or options recited are available to use or select from. 
     Additional Notes 
     Throughout this specification, plural instances may implement components, operations, or structures described as a single instance. Although individual operations of one or more methods are illustrated and described as separate operations, one or more of the individual operations may be performed concurrently, and nothing requires that the operations be performed in the order illustrated. Structures and functionality presented as separate components in example configurations may be implemented as a combined structure or component. Similarly, structures and functionality presented as a single component may be implemented as separate components. These and other variations, modifications, additions, and improvements fall within the scope of the subject matter herein. 
     Although an overview of the inventive subject matter has been described with reference to specific example embodiments, various modifications and changes may be made to these embodiments without departing from the broader scope of embodiments of the present disclosure. Such embodiments of the inventive subject matter may be referred to herein, individually or collectively, by the term “invention” merely for convenience and without intending to voluntarily limit the scope of this application to any single disclosure or inventive concept if more than one is, in fact, disclosed. 
     The embodiments illustrated herein are described in sufficient detail to enable those skilled in the art to practice the teachings disclosed. Other embodiments may be used and derived therefrom, such that structural and logical substitutions and changes may be made without departing from the scope of this disclosure. The disclosure, therefore, is not to be taken in a limiting sense, and the scope of various embodiments includes the full range of equivalents to which the disclosed subject matter is entitled. 
     As used herein, the term “or” may be construed in either an inclusive or exclusive sense. Moreover, plural instances may be provided for resources, operations, or structures described herein as a single instance. Additionally, boundaries between various resources, operations, modules, engines, and data stores are somewhat arbitrary, and particular operations are illustrated in a context of specific illustrative configurations. Other allocations of functionality are envisioned and may fall within a scope of various embodiments of the present disclosure. In general, structures and functionality presented as separate resources in the example configurations may be implemented as a combined structure or resource. Similarly, structures and functionality presented as a single resource may be implemented as separate resources. These and other variations, modifications, additions, and improvements fall within a scope of embodiments of the present disclosure as represented by the appended claims. The specification and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive sense. 
     Each of these non-limiting examples can stand on its own, or can be combined in various permutations or combinations with one or more of the other examples. 
     The above detailed description includes references to the accompanying drawings, which form a part of the detailed description. The drawings show, by way of illustration, specific embodiments in which the invention can be practiced. These embodiments are also referred to herein as “examples.” Such examples can include elements in addition to those shown or described. However, the present inventors also contemplate examples in which only those elements shown or described are provided. Moreover, the present inventors also contemplate examples using any combination or permutation of those elements shown or described (or one or more aspects thereof), either with respect to a particular example (or one or more aspects thereof), or with respect to other examples (or one or more aspects thereof) shown or described herein. 
     In the event of inconsistent usages between this document and any documents so incorporated by reference, the usage in this document controls. 
     In this document, the terms “a” or “an” are used, as is common in patent documents, to include one or more than one, independent of any other instances or usages of “at least one” or “one or more.” In this document, the term “or” is used to refer to a nonexclusive or, such that “A or B” includes “A but not B,” “B but not A,” and “A and B,” unless otherwise indicated. In this document, the terms “including” and “in which” are used as the plain-English equivalents of the respective terms “comprising” and “wherein.” Also, in the following claims, the terms “including” and “comprising” are open-ended, that is, a system, device, article, composition, formulation, or process that includes elements in addition to those listed after such a term in a claim are still deemed to fall within the scope of that claim. Moreover, in the following claims, the terms “first,” “second,” and “third,” etc. are used merely as labels, and are not intended to impose numerical requirements on their objects. 
     Method (process) examples described herein, such as the footwear assembly examples, can include machine or robotic implementations at least in part. 
     The above description is intended to be illustrative, and not restrictive. For example, the above-described examples (or one or more aspects thereof) may be used in combination with each other. Other embodiments can be used, such as by one of ordinary skill in the art upon reviewing the above description. An Abstract, if provided, is included to comply with 37 C.F.R. § 1.72(b), to allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. Also, in the above Description, various features may be grouped together to streamline the disclosure. This should not be interpreted as intending that an unclaimed disclosed feature is essential to any claim. Rather, inventive subject matter may lie in less than all features of a particular disclosed embodiment. Thus, the following claims are hereby incorporated into the Detailed Description as examples or embodiments, with each claim standing on its own as a separate embodiment, and it is contemplated that such embodiments can be combined with each other in various combinations or permutations. The scope of the invention should be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.