Patent Publication Number: US-2022225733-A1

Title: Heel tip cushion with anchoring mechanism inside heel stem

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a continuation of U.S. patent application Ser. No. 16/148,699, filed on Oct. 1, 2018, now allowed, which claims priority to and is a continuation-in-part of U.S. patent application Ser. No. 15/488,269, filed Apr. 14, 2017, now abandoned, the contents of which is incorporated by reference herein in its entirety. 
    
    
     FIELD OF THE INVENTION 
     The present disclosure relates to high heel footwear, and more particularly to a top lift assembly of a heel stem having an anchoring mechanism and a cushioning feature. 
     BACKGROUND 
     Existing designs of the heel tip for a high heel have many drawbacks and flaws, including the materials used, design and engineering of the heel tip, and how it is attached to the heel. Heel tips are used for protection against the severe abrasive pressure on the heel during normal walking. Various types of heel tips have been devised, but at the present time, conventional heel tips consist of a hard polyurethane or plastic/rubber mix molded around a metal nail head with the nail stem protruding beyond the polyurethane material. To securely fasten the heel tip to the heel, the nail stem is driven into a bore extending along the inside of the heel. 
     A large amount of stress and pressure is concentrated on a heel tip from the impact against the ground, especially when walking on uneven or high-friction surfaces such as concrete. Such forces, coupled with the small surface area of the heel, often cause heel tips to wear out or get pulled out of or dislodged from the heel within a few weeks of wear. 
     When heel tips need to be replaced, most people delay the replacement and continue to walk on worn out heel tips, sometimes wearing the heel tips away completely until remnants of the metal nail head are all that remain. Walking on worn out heel tips involves a variety of adverse and potentially dangerous side effects. 
     First, the harmful shock waves that are transmitted through the body as the metal nail head hits the surface can cause damage ranging from the feet all the way up to the neck. Second, the nail head can mark, scrape and damage floors. Also, the metal nail head is very smooth, which increases the risk of slipping or falling while walking. As a result, walking on a worn-out heel tip can cause damage to the heel by fraying, erosion, and other destruction from friction. Lastly, the exposed metal nail makes a loud, distinct clicking sound as it strikes the ground during walking which is audibly distracting to the wearer and to others. 
     Aspects of the present disclosure overcome these and other problems. 
     BRIEF SUMMARY 
     Aspects of the present disclosure solve or overcome at least the above-stated problems and disadvantages. Currently, there is no commercially available heel tip that does not wear out within a few weeks of use. A wearer must or ought to replace the heel tips, on average, every 30 days if that heel tip can even stay attached to the heel that long. An objective of aspects of the present disclosure is to provide a stronger heel tip that can take years of use and abuse before it starts to deteriorate, cannot get pulled out of the heel when worn and used and will help to absorb the harmful shock waves that are sent throughout the entire body with every step. 
     The heel tip is made of longer-wearing, resilient materials. One of these materials protects the body from the harmful shockwaves that are caused by every step, jump or stride that the high-heel wearer takes. It has been demonstrated in several studies that the rubber material of this invention stops the harmful shock waves that accumulate over time as damage to the body from our feet to the base of our skull from the repeated exposure the shock waves caused by daily activity. 
     Conventional heel tips are made of solid polyurethane, which does not deter the damage from the exposure of the shock waves that can cause numerous chronic injuries. By contrast, according to the present disclosure, some aspects provide a micro honeycomb internal structure in the heel tip to decrease the shock waves the body is absorbing as the high-heel wearer walks, runs or jumps. The micro honeycomb significantly decreases both the amplitude of the high frequency forces and their ability to propagate up into the body thus eliminating chronic pain and injuries that can diminish the high-heel wearer&#39;s ability to function at a normal level. 
     Furthermore, conventional heel tips have a nail or a steel pin that protrudes from the polyurethane material and is hammered or driven into the bore of the heel to hold the heel tip in place against the heel. By contrast, aspects of the present disclosure provide various combinations of anti-rotation, securing, and alignment promoting features to prevent rotation or slippage of the heel tip, secure the heel tip to the heel in a fixed, unmovable manner, and align the heel tip to the heel. According to some aspects of the present disclosure, a threaded insert or expansion anchor can be set in the heel and the heel tip, which can include a square or propeller head screw, with the micro honeycomb structure, is then rotated until the threaded insert locks the screw into place or the expansion anchor opens, locking the screw and heel tip securely into the heel. Optionally, the heel tip can be removed easily, by counter-rotating it, for example, to replace it with a new one or swap it entirely out for a different style. 
     According to an aspect of the present disclosure, a high heel footwear is disclosed, wherein the high heel footwear further includes a heel tip assembly and a heel assembly. The heel tip assembly is configured to be coupled with a heel of a high heel footwear. The heel tip assembly includes a top lift, a rigid shaft member, and a first wedge-lock feature. The top lift can be configured to abut an end of the heel of the high heel footwear. The rigid shaft member can extend away from the top lift and have a threaded portion. The first wedge-lock feature can prevent the top lift from rotating relative to the heel when the top lift is fully secured to the heel by the threaded portion. The heel assembly can include a threaded insert, a spring, a hollow insert, and a second wedge-lock feature. The threaded insert can be received inside an opening formed in the heel to receive the threaded portion of the rigid shaft member. The spring can also be received inside the opening and can abut the threaded insert. The spring can receive the rigid shaft member. The hollow insert can be received inside the opening and abut the spring. The hollow insert can also receive the rigid shaft member. The second wedge-lock feature can be at the end of the heel and can lock with the first wedge-lock feature. The top lift will therefore be retained relative to the end of the heel. 
     In some examples, the hollow insert can have a conical shape and can be press-fit into the opening. 
     In some examples, the first wedge-lock feature can include an alignment feature configured to align the top lift relative to the heel. The alignment can occur such that an irregular outer profile of the top lift co-aligns with a corresponding irregular outer profile of the heel at an interface between the top lift and the heel. 
     In some examples, the first wedge-lock feature and the second wedge-lock feature can be composed of metal or a material that includes metal. 
     In some examples, the spring can be a helical spring. The helical spring can compress as the threaded portion is screwed into the threaded insert. 
     In some examples, a top portion of the top lift lies on a horizontal plane below a horizontal plane of a bottommost part of a sole of the high heel footwear in an unloaded configuration. Therefore, the top lift can compress under a loaded configuration such that the top portion lies on the same horizontal plane as the bottommost part of the sole. 
     In some examples, the first wedge-lock feature can be composed of a material including a metal. The first wedge-lock feature can be secured to the top lift. 
     In some examples, the base portion can be composed of a tire tread material 
     Another embodiment of the present disclosure can provide a heel assembly for high heel footwear. The heel assembly can include a threaded insert, a shaft member, and a top lift. The threaded insert can be received in an opening formed in a heel of the high heel footwear. The threaded insert can further include an elastic portion and a threaded interior end portion. The shaft member can include a threaded end portion. The shaft member can be configured to be received in a hollow interior of the threaded insert. The top lift can be configured to couple with the end of the shaft member and abut an end of the high heel footwear. 
     In some examples, the threaded insert, the shaft member, and the top lift comprise 3D-printed material. 
     In some examples, the elastic portion can be a helical spring. 
     In some examples, the threaded insert can compress at the elastic portion in response to threading the threaded end portion of the shaft member into the threaded interior end portion of the threaded insert. 
     In some examples, the heel assembly can further include an adhesive element between the threaded insert and the heel opening. 
     In some examples, the shaft member can include a polygonal head. The top lift can include a polygonal cutout portion configured to receive the polygonal head of the shaft member. 
     In some examples, the threaded insert can form an interference fit against the opening in the heel of the high-heel footwear. 
     In some examples, the top lift can be coupled with the end of the shaft member. The shaft member can be received into the hollow interior of the threaded insert and screwed into the threaded interior. For example, a user can perform the coupling and screwing steps. Therefore, the heel assembly can form a unitary element. The unitary element cannot be disassembled without an applied force. Such an applied force must unscrew the shaft member with a force greater than a compression force of the elastic member. For example, a user can unscrew the shaft member with an appropriate force. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an example high heel footwear having a relatively narrow heel that incorporates a heel tip assembly according to an aspect of the present disclosure. 
         FIG. 2  is a perspective view of another example high heel footwear having a wider heel compared to the high heel footwear shown in  FIG. 1 , and which incorporates a heel tip assembly according to another aspect of the present disclosure. 
         FIGS. 3A and 3B  illustrate two different sized heel tip assemblies according to an aspect of the present disclosure. 
         FIG. 4A  illustrates an exemplary elongated threaded insert having a hole or bore through the center of a threaded insert, which is inserted into a heel according to aspects of the present disclosure. 
         FIG. 4B  illustrates an example threaded hole or bore formed within or tapped into the heel with threads to receive threads of a top lift according to aspects of the present disclosure. 
         FIGS. 5A and 5B  illustrate two example implementations of a heel tip assembly having a top lift with a honeycomb or micro honeycomb pattern made from tire material. 
         FIG. 6A  illustrates a heel having a threaded shaft  502  threaded into a threaded insert that is secured into a hole or bore of a heel. 
         FIG. 6B  illustrates a heel having a threaded shaft threaded into the threaded hole or bore that is tapped into the heel 
         FIGS. 7A and 7B  illustrate two examples of a heel tip assembly having a top lift including two types of honeycomb patterns. 
         FIG. 8  is an example of another top lift having a base portion made of a solid tire tread material. 
         FIGS. 9A and 9B  illustrate side and end views, respectively, of a top lift having rotation, securing, and alignment features. 
         FIGS. 10A and 10B  illustrate two additional implementations of a heel tip assembly according to the present disclosure, featuring a different anti-rotation and alignment feature than disclosed in connection with  FIGS. 9A and 9B . 
         FIG. 11  illustrates a top lift having a screw-actuated anchor to secure the top lift within the heel of the top lift assembly. 
         FIGS. 12A and 12B  illustrate another way of securing a top lift to a heel of a wider heel, such as shown in  FIG. 2 . 
         FIGS. 13A and 13B  illustrate yet another way of securing any top lift into any heel disclosed herein using springs inside the heel. 
         FIG. 14  shows two example isometric views of the top lift disclosed in connection with  FIGS. 13A and 13B . 
         FIG. 15  illustrates another example where a heel includes ball bearings to receive corresponding detents formed in a shaft of a top lift but lacks a square base feature. 
         FIG. 16  illustrates two exemplary regularly and non-regularly shaped top lifts having shafts with slots to lock into corresponding features in the heel. 
         FIGS. 17A and 17B  illustrate how the top lift can be slightly longer than the outsole of the high heel footwear when no load is present in the footwear. 
         FIG. 18  illustrates a heel tip assembly having a threaded insert that is held in tension inside the heel by a spring. 
         FIG. 19  illustrates the heel tip assembly of  FIG. 18  with the threaded insert fully screwed into the heel and held against it by the spring. 
         FIG. 20  is a top view of the heel taken along line  20 - 20  shown in  FIG. 18 . 
         FIG. 21  is a bottom view of the top lift taken along line  21 - 21  shown in  FIG. 18 . 
         FIGS. 22A-22D  show an exemplary heel tip assembly having a top lift with a rigid shaft and insert according to another aspect of the present disclosure. 
         FIGS. 23A, 23B, and 23C  show another exemplary heel tip assembly according to another embodiment of the present disclosure. 
         FIG. 24  shows still another exemplary heel tip assembly according to another embodiment of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  is a perspective view of an example high heel footwear  100  having a relatively narrow heel that incorporates a heel tip assembly  102  according to an aspect of the present disclosure. The term “footwear” encompasses shoes, boots, sandals, flip flops, and any other apparatus worn on the foot and designed or intended to be worn by either men or women or both. The term “high heel” has its ordinary meaning to those skilled in the art of footwear, and those of ordinary skill in the art of footwear will appreciate the dimensions and characteristics of a footwear item having a high heel. For example, stiletto type heels can have a heel height of about 4-6 inches or even higher. Squatter, high heel boots (including those worn by men), for example, can have a heel height of about 3-4 inches. According to some aspects, a minimum heel height to qualify as a high heel is about 2 inches. The present disclosure also contemplates so-called platform footwear, so long as there is a distinct outsole portion and distinct heel portion. As shown in  FIG. 1 , the various parts of a high heel footwear  100  are conventionally labeled as an outsole  106 , a toe box  108 , a counter  110 , a breast  112  of the heel, a heel  114 , a seat  116 , a shank  118 , and a top lift  120 . The top lift  120  can variously also be referred to as the top piece, the heel tip, the heel lift, or the heel cap, and these terms are used interchangeably herein. The width of the top lift  120  can vary, from narrow in the case of a stiletto heel, to relatively wide as used on a boot or a platform shoe, and aspects of the present disclosure can be used on any top lift  120 , from narrow to wide. 
     For reading convenience, the same reference numbers are used throughout this disclosure to refer to the same item or feature even though they might appear in different embodiments. Where that item or feature differs, a different reference number or an apostrophe is used to indicate that the disclosure is describing a different item or feature. The terms used in this description have their ordinary meaning as understood by those skilled in the art of footwear, tire technology, and mechanical devices. 
       FIG. 2  is a perspective view of another example high heel footwear  100 ′ having a wider heel  114 ′ compared to the high heel footwear shown in  FIG. 1 , and which incorporates a heel tip assembly  102 ′ according to another aspect of the present disclosure. The same reference numbers are used to refer to the same parts. The high heel footwear  100 ′ has a thicker heel  114 ′ compared to the heel  114  of the high heel footwear  100  shown in  FIG. 1 . The cross-section of the heel  114 ,  114 ′ can be regular, such as circular such as shown in  FIGS. 14 and 16A , or irregular such as shown in  FIGS. 14 and 16B . Throughout this disclosure, for reading convenience, each heel tip assembly  102 ,  102 ′ will be referred to with these reference numbers even though different embodiments may be described. 
       FIGS. 3A and 3B  illustrate two different sized heel tip assemblies  102 ,  102 ′ according to an aspect of the present disclosure. The heel tip assembly  102 ,  102 ′ generally includes a securing feature part  300 ,  300 ′, respectively. In this example, the securing feature takes the form of threads  302 . Generally, a securing feature refers to a feature, such as a tangible feature, that permanently or removably secures one part to another in a manner that inhibits movement (by rotation, twisting, or otherwise) of the two parts relative to each other. The securing feature part  302 ,  302 ′ also has a shaft portion those threads  302 ,  302 ′ are threaded by rotation into a corresponding threaded insert inside the heel  114 ,  114 ′ as described herein. In  FIG. 3B , the top lift  120 ′ of the heel tip assembly  102 ′ has an irregular contour to match the contour of the heel  114 ′ to which the top lift  120 ′ is secured. As described here, an alignment feature can also be present to ensure that the contours of the top lift and the heel co-align. As the top lift  120 ′ is screwed into place, depending on the alignment of the threads, the top lift  120 ′ may have a tendency to stop rotating at a point where its outer contour is misaligned relative to the heel  114 ′. To avoid this scenario, various aspects of the present disclosure describe alignment features that aid in co-aligning the top lift with the heel in a facile way during assembly or construction of the footwear  100 ,  100 ′. 
     Turning now to the heel side of the footwear,  FIG. 4A  illustrates an exemplary elongated threaded insert  400  having a hole or bore  402  through the center of a threaded insert  400 , which is inserted through a hole or bore  410  of the heel  114 ,  114 ′. The threaded insert  400  is inserted into the hole or bore  410  of the heel  114 ,  114 ′ so that an end opening  404  of the threaded insert  400  can receive the securing feature part  300 ,  300 ′ of a heel tip assembly  102 ,  102 ′. The threaded insert  400  can be secured to the heel  114 ,  114 ′ by glue or interference fit, for example. Alternately, in  FIG. 4B , a threaded hole or bore  410  is formed within or tapped into the heel  114 ,  114 ′ with threads  406  that are configured to receive the threads  302  of the securing feature part  300 ,  300 ′. 
       FIGS. 5A and 5B  illustrate two example implementations of a heel tip assembly  102 ,  102 ′ having a top lift  120 ,  120 ′ with a honeycomb or micro honeycomb pattern made from tire material, including a rubber compound and fillers such as fiber or textiles. Any of the honeycomb or micro honeycomb patterns or structures disclosed herein can be printed by a 3D printing technique, such as digital light synthesis. The top lift  120 ,  120 ′ has a base portion  504 , a central portion  506 , and a top portion  508 . The cross-section of the central portion  506  has a honeycomb pattern. The illustrations are not schematic representations of the actual honeycomb pattern. Indeed, the honeycomb pattern is shown for ease of illustration so that the reader can readily see the pattern; however, the size of the honeycombs can vary from the size actually shown. For example, the honeycombs can be made larger, or the walls of the honeycomb can be thicker. The honeycomb pattern allows the top lift  120 ,  120 ′ to compress or deform slightly under load, and more so than if the top lift  120 ,  120 ′ were made from a solid material such as rubber. The honeycombs of the pattern are arranged to so as to compress along a vertical direction when a load is presented at the top of the honeycomb, thereby providing a cushioning effect to the wearer of the high heel footwear. The top portion  508  (i.e., the part that contacts the ground surface) can be a tire tread material or composed of solid rubber having a tread-like pattern facing the ground to enhance the grip and friction coefficient relative to the ground surface. The base portion  504  can be composed of, for example, metal, such as the same metal as a threaded shaft  502  that extends away from the base portion  504 , and the central portion  506  can be secured or attached permanently to the base portion  504  by an adhesive or any other conventional process to permanently affix the two different interface materials together. Another interface  510  is present between the exposed surface of the base portion  504  and the exposed surface of the bottom of the heel  114 ,  114 ′ before the top lift  120 ,  120 ′ is secured to the heel  114 ,  114 ′. At this interface, an adhesive or other method of permanently affixing the base portion  504  to the bottom of the heel  114 ,  114 ′ can be used after the securing feature in the form of a threaded shaft  502 ,  502 ′ is screwed into the corresponding threaded insert  400  or threads  406  inside the bore  410  of the heel  114 ,  114 ′. As the wearer walks with the heel top assembly  102 ,  102 ′ installed in the footwear  100 ,  100 ′, the honeycomb structure of the central portion  506  will compress and bulge outwardly, providing a soft cushion for the wearer and absorb and dissipate shock waves emitted each time the top portion  508  contacts the ground surface. 
     Example dimensions of the top lift  120 ,  120 ′ are as follows. The length, width, or diameter of the top lift  120 ,  120 ′ match the corresponding length, width, or diameter of the heel  114 ,  114 ′ to which the heel tip assembly  102 ,  102 ′ is attached so that the outer contour of the heel at the interface  116  matches the outer contour of the top lift  120 ,  120 ′. Beyond the interface, the contour of the top lift  120 ,  120 ′ can diverge from that of the heel  114 ,  114 ′. For example, the top lift  120 ,  120 ′ can flare outwardly or taper inwardly starting from the interface  116  toward the top portion  508 . 
       FIGS. 6A and 6B  illustrate two examples where the top lift  120 ,  120 ′ has a top portion  606  made of a solid rubber material that is glued or otherwise permanently affixed to a base portion  604  of a heel tip assembly  102 ,  102 ′. The base portion  604  can be made of the same material as the threaded shaft  502 , such as metal, to form an anti-rotation feature and a securing feature for the top lift  120 ,  120 ′. The outer contour of the base portion  604  and the top portion  606  matches the outer contour of the exposed end of the heel  114 ,  114 ′ at the interface  116 ,  510  so that at the interface  116 ,  510 , there is no perceptible discontinuity from the heel  114 ,  114 ′ to the top lift  606 . In  FIG. 6A , the threaded shaft  502  is threaded into the threaded insert  400  that is secured into the hole or bore  410  of the heel  114 ,  114 ′. In  FIG. 6B , the threaded shaft  502 ′ is threaded into the threaded hole or bore  410  that is tapped into the heel  114 ,  114 ′ with threads  406  that are configured to receive the threads of the threaded shaft  502 ′, which provides a securing feature and an anti-rotation feature relative to the heel  114 ,  114 ′. This embodiment is particularly suited for thicker diameter heels, such as the heel  114 ′ shown in  FIG. 2 . 
       FIGS. 7A and 7B  illustrate two examples of a heel tip assembly  102 ,  102 ′ having a top lift including two types of honeycomb patterns  703 ,  705 ,  706  such as shown as honeycomb pattern  506  in  FIGS. 5A and 5B . The top lift has a central portion  706  made from a tire material and having a honeycomb pattern. On either side of the central portion  706 , there are encapsulating portions  703 ,  705  also made from a tire material and having a denser honeycomb pattern compared to that of the central portion  706 . Thus, the central portion  706  has more “give” under compression, whereas the denser surrounding encapsulating portions  703 , 705  have less give, thereby providing more cushioning against shocks and vibrations that would otherwise be transmitted up the leg of the wearer. The top portion  708  can be made of a tire tread material or composed of solid rubber having a tread-like pattern facing the ground to enhance the grip and friction coefficient relative to the ground surface and to provide a softer or quieter interface with the surface on which the footwear is traversing compared to conventional materials used for a high heel top. A base portion  704  fixed to the encapsulating portion  703  can be composed of, for example, metal, such as the same metal as a threaded shaft  502  that extends away from the base portion  704 , and the encapsulating portion  703  can be secured or attached permanently to the base portion  704  by an adhesive or any other conventional process to permanently affix the two different interface materials together. The threaded shaft  502  is screwed into an elongated threaded insert  400  having a hole or bore  402  through the center of a threaded insert  400 , which is inserted through a hole or bore  410  of the heel  114 ,  114 ′, to form an anti-rotation feature and a securing feature. When fully screwed in place at the interface  116 ,  510 , the outer contour of the top lift matches an outer contour of the heel  114 ,  114 ′ at the interface  116 ,  510  so that no visual discontinuities can be perceived. The colors of the top lift and heel can also be matched to further the visual effect. The embodiment of  FIG. 7B  is identical except that the heel  114 ,  114 ′ is wider and can accommodate a larger top lift and therefore more tire tread and honeycomb material. 
     The drawings shown herein are not necessarily shown to scale and some features may be exaggerated so that the various layers can be seen by the reader. The top lifts of the present disclosure can have the same dimensions as conventional top lifts used in high heel footwear. 
       FIG. 8  is an example of another top lift  120 ,  120 ′ that can be used with any heel  114 ,  114 ′ disclosed herein. Here, a base portion  804  of the top lift shown in  FIG. 8  can be made of a solid tire tread material, for example, or of a material that includes rubber. A threaded shaft  802  extends from the base portion  804  and includes a head  803  having teeth  805  around a diameter of the head which prevent the shaft  802  from rotating relative to the base portion  804  when the threaded shaft  802  is screwed into a corresponding threaded hole or bore in the heel  114 ,  114 ′. The teeth  805  provide an anti-rotation and a securing feature to prevent rotation of the base portion  804  and to secure it to the heel  114 ,  114 ′. The head  803  and teeth  805  are embedded within the base portion  804  so only the threaded shaft  802  can be seen emerging from the base portion  804 . 
       FIGS. 9A and 9B  illustrate side and end views, respectively, of a top lift  120 ,  120 ′ having rotation, securing, and alignment features. A base portion  904  forms an alignment feature, which can have a non-circular cross-section to co-align the base portion  904  relative to the heel  114 ,  114 ′ so that the outer contours of the base portion  904  and the heel  114 ,  114 ′ match. The base portion  904  also forms an anti-rotation feature, preventing the top lift  120 ,  120 ′ from rotating once fully inserted into the heel  114 ,  114 ′. The top lift  120 ,  120 ′ also includes a conical tapered portion  902  that tapers toward a seat or interface  116  of the heel  114 ,  114 ′ as shown in  FIG. 9A . The conical tapered portion  902  is inserted into a bore  922  through a hole  920  that has a corresponding section that receives the base portion  904  (seen in  FIG. 9B ), and has a width W that is slightly smaller than a width W′ of the widest part of the conical tapered portion  902  to form an interference fit inside the bore  922  of the heel  114 ,  114 ′. The rest of the top lift  120 ,  120 ′ can be like any of the top lifts disclosed herein; however, in the example of  FIG. 9A , the top lift  120 ,  120 ′ includes a central portion  908  having a honeycomb pattern made from tire material, including a rubber compound and fillers such as fiber or textiles. The cross-section of the central portion  908  has a honeycomb pattern. The top lift  120 ,  120 ′ also includes a top portion  910  (i.e., the part that contacts the ground surface) composed of a tire tread material or of solid rubber having a tread-like pattern facing the ground to enhance the grip and friction coefficient relative to the ground surface. The base portion  906  can be composed of, for example, metal, such as the same metal as the conical tapered portion  902  as shown by the cross section in  FIG. 9A . To insert the top lift  120 ,  120 ′ into the bore  922 , the top portion  910  can be tapped in, after aligning the non-circular base portion  904  with the hole  920  so that the (irregular) profiles of the heel and top lift match. 
       FIGS. 10A and 10B  illustrate two additional implementations of a heel tip assembly according to the present disclosure, featuring a different anti-rotation and alignment feature than disclosed in connection with  FIGS. 9A and 9B . Here, a shaft member  1002  of the top lift  120 ,  120 ′ includes a first spring element  1004   a  and a second spring element  1004   b , which each protrudes away from an elongated surface of the shaft member  1002 . The spring elements  1004   a ,  1004   b  form a securing feature part and are biased away from the elongated surface of the shaft member  1002 . A base portion  1004  of the top lift  120 ,  120 ′ is attached to the shaft member  1002 , or the base portion  1004  and the shaft member  1002  can be a unitary, integral piece. 
     The heel  114 ,  114 ′ includes a hole  1020  and a non-threaded bore  1012  having a first detent  1010   a  and a second detent  1010   b  arranged to receive the spring elements  1004   a ,  1004   b , respectively, when the shaft member  1002  is inserted into the bore  1012  through the hole  1020 . Because the spring elements  1004   a ,  1004   b  are biased outwardly, they will initially be forced inwardly against the shaft member  1002  until they snap outwardly into place within the detents  1010   a ,  1010   b  to form a securing feature but also an anti-rotation and an alignment feature. The rest of the top lift  120 ,  120 ′ in this example includes a central portion  1006  having a honeycomb pattern composed of a tire tread material, and a top portion  1008 , which can be composed of a solid tire tread material or rubber. 
     In  FIG. 10B , the shaft member  1002 ′ is threaded, and the threaded insert  1014  includes a threaded portion  1016  with threads and a non-threaded portion near a hole  1018  through which the threaded shaft member  1002 ′ is inserted. The threaded shaft member  1002 ′ is rotated into the threads of the threaded portion  1016  until the spring elements  1004   a ,  1004   b  click into place within the detents  1010   a ,  1010   b  of the non-threaded portion, to secure the top lift  120 ,  120 ′ to the heel  114 ,  114 ′, prevent it from rotating, and co-aligning the two parts so that the respective outer contours match around their entire circumference. 
       FIG. 11  illustrates a top lift having a screw-actuated anchor to secure the top lift within the heel of the top lift assembly. The screw-actuated anchor  1102  includes a first arm  1106   a  and a second arm  1106   b  that flare outwardly from a shaft member  1004  having threads. A base portion  1108  can be made of metal and includes a hole through which the shaft member  1004  extends and terminates at a head  1126  having a tool receiving portion  1128  to receive a tool that rotates the screw-actuated anchor  1102  inserted into the hole  1110 . After the screw-actuated anchor  1102  is fully inserted into the hole  1110  of the heel  114 ,  114 ′, a tool is inserted into the tool receiving portion  1128  of the head  1126  and rotated in situ within the hole  1110 , which rotation causes the arms  1106   a,b  to begin to extend outwardly toward the inner surface  1112  of the hole  1110  of the heel  114 ,  114 ′ until the arms  1106   a,b  press expand the width W of the hole  1110  to provide an anti-rotation feature, which prevents the top lift  120 ,  120 ′ from rotating or becoming mis-aligned during usage of the high heel footwear. The top lift portion  120 ,  120 ′ includes a hole  1124  so that a tool can be received in the tool receiving portion  1128 . This hole can be plugged after installation with a material to match that of the top lift portion  120 ,  120 ′, such as a tire tread material. The top portion  1122  can be made of a tire tread material. An insert made from the same tire tread material can be used to plug the hole  1124 . The central portion  1120  can have a honeycomb pattern to provide cushioning as discussed above. The arms  1106   a,b  allow minute adjustments of the top lift portion  120 ,  120 ′ within the heel  114 ,  114 ′ to co-align the two parts perfectly while the final position is determined by forcing the arms  1106   a,b  apart as much as the material of the heel  114 ,  114 ′ will allow without damage. 
       FIGS. 12A and 12B  illustrate another way of securing a top lift  120 ′ to a heel  114 ′ of a wider heel, such as shown in  FIG. 2 . A hollow, self-tapping insert  1200  (shown in  FIG. 12A ) is screwed into a base of the heel  114 ′, which can be composed of plastic on its interior, making it suitable for receiving a self-tapping insert. The top lift  120 ′ includes a base portion  1206 , which can be composed of a metal material, a central portion  1208  having a honeycomb pattern and composed of a tire tread material, and a top portion  1212 , which can be composed of a tire tread material having a tread pattern facing the ground. A shaft member  1202  having threads  1204  can be made of metal and is threadably received within the self-tapping insert  1200  installed in the heel  114 ′, thereby providing an anti-rotation and securing feature for the top lift assembly. 
       FIGS. 13A and 13B  illustrate yet another way of securing any top lift into any heel disclosed herein using springs inside the heel. The top lift  120 ,  120 ′ includes a shaft member  1302  having a first receptacle  1304   a  and a second receptacle  1304   b  formed along a curved surface  1305  of the shaft member  1302  and a non-circular base portion  1306  that forms an alignment and anti-rotation feature for the top lift  120 ,  120 ′. The heel  114 ,  114 ′ includes an insert assembly  1320  having a hole  1330  that narrows to a narrow portion  1322 . The insert assembly  1320  includes a first spring  1328   a  and a second spring  1328   b  and a balls  1340   a ,  1340   b  that protrude from corresponding openings  1326   a,b  extending through a wall  1324  of the insert assembly  1320 . The balls  1340   a,b  extend into the opening  1330  of the insert assembly  1320  until the shaft member  1302  is inserted through the opening  1330 . When the balls  1340   a,b  align with the receptacles  1304   a,b  of the shaft member  1302 , the springs  1328   a,b  allow the balls  1340   a,b  to compress the springs  1328   a,b  like a plunger element as the shaft member  1302  is inserted into the narrow portion  1322  of the insert assembly  1320  until the receptacles  1304   a,b  receive the balls  1340   a,b  and secure the top lift  120 ,  120 ′ relative to the heel  114 ,  114 ′. The non-circular base portion  1306  (e.g., square) fits into the non-circular opening  1330  (e.g., square) to maintain an alignment of the top lift  120 ,  120 ′, which can have a non-regular outer contour, relative to the heel  114 ,  114 ′ (shown in  FIG. 13B ). 
       FIG. 14  shows two example isometric views of the top lift  120 ,  120 ′ disclosed in connection with  FIGS. 13A and 13B . One of the examples has a regular profile (circular), whereas the other has a non-regular or irregular profile. A round shaft  1402  has detents  1404  to be received in corresponding ball bearings inside the heel  114 ,  114 ′ as disclosed in connection with  FIGS. 13A and 13B . A base  1406  has a square shape and can be made of metal along with the round shaft  1402 . The top portion  1408  can include a honeycomb pattern composed of a tire tread material as disclosed above. The square base  1406  permits alignment of the top lift  120 ,  120 ′ relative to a heel  114 ,  114 ′ having a non-regular outer contour. 
       FIG. 15  illustrates another example where a heel includes ball bearings to receive corresponding detents formed in a shaft of a top lift but lacks a square base feature. The same reference numbers are used, except that the top lift  120 ,  120 ′ lacks the base  1406  shown in  FIGS. 13A and 13B . This implementation is suitable, for example, for a round heel  114 ,  114 ′. 
       FIG. 16  illustrates two exemplary regularly and non-regularly shaped top lifts  120 ,  120 ′ having shafts  1602  with slots  1604  to lock into corresponding features in the heel  114 ,  114 ′ as disclosed above. 
       FIGS. 17A and 17B  illustrate how the top lift  120 ,  120 ′ can be slightly longer than the outsole of the high heel footwear  100 ,  100 ′ when no load is present in the footwear  100 ,  100 ′. In  FIG. 17A , the top lift  120 ,  120 ′ extends below the outsole by a distance, d, to provide a total distance from the base to top of the top lift corresponding to a distance D. However, under compression by a load  1700 , the top lift  120 ,  120 ′ as shown in  FIG. 17B  compresses to reduce the overall distance, D′&lt;D, so that the top lift  120 ,  120 ′ is aligned on a horizontal plane  1702  with the outsole of the high heel footwear  100 ,  100 ′. Because the top lift  120 ,  120 ′ can compress, such as due to the honeycomb tire tread material, designing the top lift  120 ,  120 ′ so that it is slightly longer under no compression allows the compression to keep the footwear level under compression. 
       FIG. 18  illustrates an exploded view of a heel  114 ,  114 ′ (shown in cross section) and a heel tip assembly  102 ,  102 ′ having a top lift  120 ,  120 ′, and a rigid shaft  1800  (e.g., made of metal) having a threaded portion  1802  that screws into a threaded bung or insert  1814  that is inserted into a bore (such as formed by drilling) or opening (such as formed by 3D printing or other additive manufacturing process)  1812  formed in the heel  114 ,  114 ′. As shown in  FIG. 18 , the threaded portion  1802  of the (at least partially) rigid shaft  1800  is inserted into the opening  1812  through a hollow cone-shaped insert  1804 , through a central axis of a coil or helical spring  1806 , and then rotated so that the threads of the threaded portion  1802  threadably engage corresponding threads  1816  in the threaded insert  1814  to secure the top lift  120 ,  120 ′ against the heel  114 ,  114 ′. As the threaded portion  1802  is rotated to threadably secure it to the threads  1816  of the threaded insert  1814 , the spring  1806  begins to compress, thereby pulling the threaded insert  1814  in a lateral direction inside the opening  1812  toward the top lift  120 ,  120 ′ in a direction D, shown in  FIG. 19 . The threaded portion  1802  is threaded toward the distal or top end of the rigid shaft  1800 , and as shown in  FIG. 18 , the bottom part of the rigid shaft  1800  does not need to be threaded. 
     As the threaded insert  1814  is pulled in the direction D shown in  FIG. 19 , a space  1900  is created above the threaded insert  1814 . The insert  1804  is fixed or anchored relative to the heel  114 ,  114 ′ and does not move laterally or rotationally relative to the heel  114 ,  114 ′. Any means of fixing the insert  1804  is contemplated. For example, the insert  1804  can have a cone shape with tapered sides  1805   a ,  1805   b  such that the widest end (d 2  shown in  FIG. 19 ) of the cone is slightly wider than a diameter of the opening  1812  (d 1 ). The insert  1804  can be tapped into the bore  1812 , such as with a hammer, until it is seated and flush with the top of the heel  114 ,  114 ′. In this manner, the insert  1804  has a press-fit or interference-fit interface with the inside of the bore  1812 . Optional adhesive can be applied along the tapered sides  1805   a,b  of the insert  1804  to further anchor the insert  1804  inside the bore  1812  in the position shown in  FIG. 18 . The insert  1804  is inserted last into the bore  1812  after the threaded insert  1814  and the spring  1806  have been installed inside the bore  1812 . 
     Because the insert  1804  is anchored inside the bore  1812 , as the threaded portion  1802  of the rigid shaft  1800  is screwed into the threaded insert  1814 , the coil or helical spring  1806  will compress, causing the threaded insert  1814  to move in a translational, but not rotational, direction D along the bore  1812  toward the top lift  120 ,  120 ′. This prevents the threaded insert  1814  from rotating as the threaded portion  1802  is screwed into the threaded insert  1814 , the overall width of the threaded insert  1814  can be made slightly larger than a diameter of the bore  1812  (d 1 ) so that the threaded insert  1814  forms an interference or press-fit interface with the inside of the bore  1812 . Alternately or additionally, one or more wings or flanges can be provided on the outer circumference of the threaded insert  1814 , such that when the threaded insert  1814  is forcibly inserted into the bore  1812 , such as by hammering or tapping the threaded insert  1814 , the wings or flanges bite into the inner sides of the heel  114 ,  114 ′, which is typically made of plastic, forging a channel along the side of the bore  1812  along which the threaded insert  1814  can slide up and down in a lateral direction D but cannot rotate about its central axis as the threaded shaft  1802  is screwed into the threaded insert  1814 . 
     The threaded shaft  1802  together with the threaded insert  1814  form a securing feature to align the top lift  120 ,  120 ′ relative to the top of the heel  114 ,  114 ′ once installed therein. Alignment and anti-rotation features are shown in  FIGS. 20 and 21 , which show respective wedge-lock features or patterns  2000 ,  2100 , which can be made of metal. The wedge-lock feature or pattern  2000  can be machined on the top  1818  of the heel  114 ,  114 ′, or attached to the exposed end of the top  1818  of the heel  114 ,  114 ′ as, for example, a metal (or hard plastic or other rigid material) washer having the wedge-lock pattern  2000 . The wedge-lock pattern  2000  corresponds to the wedge-lock feature or pattern  2100  formed on the heel-interfacing surface  1820  of the top lift  120 ,  120 ′. The wedge-lock pattern  2100  can also be attached to the top lift  120 ,  120 ′ as, for example, a metal washer having the wedge-lock pattern  2100 . Because the top part of the top lift  120 ,  120 ′ (the part that contacts the ground) is made of, for example, a material including rubber, having the wedge-lock pattern  2100  made from a more robust material, such as a material including metal or a hard plastic or other rigid material, allows a more secure and reliable interface to be established with the heel  114 ,  114 ′. When the wedge-lock pattern  2100  is formed as, for example, a metal or plastic washer, the metal washer is securely attached, such as by adhesive, to the rubber part of the top lift  120 ,  120 ′. As the heel-interfacing surface  1820  of the top lift  114 ,  114 ′ mates with the corresponding wedge-lock pattern  2000  on the top  1818  of the heel  114 ,  114 ′ as the top lift  120 ,  120 ′ is being rotated to secure the threaded shaft  1802  inside the threaded insert  1814 , the corresponding wedge patterns lock the two pieces  120 ,  120 ′ and  114 ,  114 ′ in a wedge-lock fashion together. The spring  1806  allows the wedge patterns  2000 ,  2100  to override one another briefly until they snap into a wedge-lock configuration as the threaded shaft  1802  is turned against the heel  114 ,  114 ′. The user or installer will receive tactile feedback as the wedge locks snap or click into place as the shaft  1802  is being tightened against the heel  114 ,  114 ′. Again, the spring  1806  provides some “give” to the shaft and top lift assembly to allow the wedges to override and lock into place. The number, shape, and position of the wedge locks in the patterns  2000 ,  2100  can be a function of the width of the heel  114 ,  114 ′ and the outer contour shape of the heel  114 ,  114 ′. 
     In the final, secured position, the wedges of the wedge lock patterns  2000 ,  2100  are locked into place against one another, and held in tension against the top  1818  of the heel  114 ,  114 ′ by the tension of the spring  1806  pushing against the fixed insert  1804 , causing the shaft  1802  to be biased in a direction away from the top  1818  of the heel  114 ,  114 ′ (e.g., in a direction opposite of direction D shown in  FIG. 19 ). 
     A method of retrofitting an existing heel is also disclosed. A cobbler or user drills the opening  1812  into the heel  114 ,  114 ′ if the opening is not already present there. The user inserts the threaded insert  1814 , which can optionally have one or more outer flanges or wings, into the opening  1812 , and then taps or hammers the threaded insert  1814  into the opening  1812 , such as with the aid of a shank or punch to seat the threaded insert  1814  all the way into the opening  1812  in the installed position shown in  FIG. 18 . Then, the user inserts the spring  1806  against the insert  1814  through the opening  1812 . To complete the heel assembly, the user inserts the insert  1804  through the opening  1812  and taps it into the opening against the spring  1806  until the insert  1804  is flush against the top  1818  of the heel  114 ,  114 ′. Optional adhesive can be applied to the insert  1804  prior to insertion to further anchor and secure it inside the bore  1812 . 
     Now that the heel  114 ,  114 ′ has been primed to receive the threaded shaft  1802 , the user inserts the threaded shaft  1802  through the opening of the insert  1804 , which then passes through the opening of the coil spring  1806 , and finally can be screwed into the threads  1816  of the threaded insert  1814  at the distal end of the bore  1812 . The user continues to rotate the threaded shaft  1802 , such as by grasping the top lift  120 ,  120 ′, to tighten the threaded shaft  1802  against the heel  114 ,  114 ′. Tactile and audible clicks can be felt and heard as the wedge locks  2000 ,  2100  secure the top lift  120 ,  120 ′ against the top  1818  of the heel  114 ,  114 ′. When the outer profile or contour of the top lift  120 ,  120 ′ and the heel  114 ,  114 ′ has an irregular geometric shape, such as shown in  FIGS. 20 and 21 , the user continues to rotate the threaded shaft  1802  until the respective contours of the top lift  120 ,  120 ′ and of the heel  114 ,  114 ′ align. 
     To remove the top lift  120 ,  120 ′, such as to replace a worn rubber tip or replace the entire top lift  120 ,  120 ′ with a new one, the user counter-rotates the top lift  120 ,  120 ′ in a direction to loosen the same from the threaded insert  1814  until the threads of the threaded shaft  1802  are free from the corresponding threads  1816  of the threaded insert  1814  and the threaded shaft  1802  can be removed from the opening  1812  and a new or replacement one can be installed. This embodiment is truly a do-it-yourself implementation, in which the wearer of the shoe can carry out the installation and/or replacement of top lifts  120 ,  120 ′ by themselves without the need to seek out a cobbler or other professional. The entire assembly can be bundled together as a kit, together with a shank or punch that can be used to fully insert the threaded insert  1814  into the opening  1812 . Importantly, replacement of an old top lift and installation of a new top lift can be carried out simply by manually (e.g., by human hand) unscrewing the old top lift and manually screwing in a new top lift without requiring any tools whatsoever. 
       FIGS. 22A-22D  show an exemplary heel tip assembly  102 ,  102 ′ having a top lift  120 ,  120 ′ comprising a rigid shaft  2202  and insert  2210 . Insert  2210  can be made of metal, plastic, or any 3D-printing material. Insert  2210  can be sized and shaped to fit within an opening in a heel (for example, the opening as discussed with respect to  FIGS. 18-19 ). Insert  2210  can comprise an elastic element  2214  and a hollow interior (shown in  FIG. 22C ) with a threaded interior  2212 . As a brief overview of the heel tip assembly of  FIGS. 22A-22C , the assembly provides for a user inserting the insert  2210  into a heel  114 ,  114 ′ (heel  114 ,  114 ′ is not pictured). The user can then put the rigid shaft  2202  through the hollow interior of the insert  2210  until the threaded end portion  2204  of the rigid shaft  2202  engages with the threaded interior  2212  of the insert  2210 . The user can screw the rigid shaft  2202  into the insert  2210  until the rigid shaft  2202  cannot be rotated further. During the screwing motion, the elastic portion  2214  will be pulled downwardly (toward the top lift  120 ,  120 ′) onto the rigid shaft  2202 . This will cause the restorative force of the rigid shaft to exert an upward pressure on the rigid shaft  2202 . The various components of the assembly are discussed in greater detail below. 
     The elastic element  2214  can be shaped as a spring or another cutaway design. The elastic element  2214  provides a restorative force to return to an original, uncompressed configuration when the elastic element  2214  is compressed by, e.g., a user or pressure from the rigid shaft  2202 . In some examples, elastic element  2214  can be a coil or helical spring designed for compression and tension. Such a spring can be designed to operate with a compression load, so that the spring compresses and becomes shorter as a load is applied to it. Therefore, as insert  2210  receives rigid shaft  2202 , the screwing motion of  2202  will pull down, or compress insert  2210 , and more specifically, compress at the elastic element  2214 . Therefore, elastic element  2214  will exert an upward pressure to uncompress. This upward pressure will pull rigid shaft  2202  further into the heel  114 ,  114 ′. 
     In other examples, elastic element  2214  can be a torsion spring, configured to receive a load by a torque or twisting force. Therefore, when rigid shaft  2202  is screwed into the threaded interior  2212 , one end of the elastic element  2214  can be configured to rotate or twist through an angle, for example, rotate clockwise. This rotating motion of the elastic element  2214  can cause elastic energy to be stored in the elastic element  2214 . The elastic element  2214  can then cause the elastic insert  2210  (and the now-attached rigid shaft  2202 ) to press upward into the heel  114 ,  114 ′ as it is pulled by the torsion&#39;s spring pressure to rotate counter-clockwise and return to an original spring state. In some examples, elastic element  2214  can therefore be a torsion spring consisting of torsion fiber, an elastic metal or rubber configured to absorb spring energy. 
     A person skilled in the art understands that elastic element  2214  can be many other types of springs, such as a variable spring, a serpentine spring, a volute spring, a Belleville spring, and/or a main spring. In some instances, elastic element  2214  can be an elastic material such as any elastomer, natural rubber, synthetic rubber, nitrile rubber, silicone rubber, urethane rubbers, chloroprene rubber, an elastic metal, and any combination thereof. Elastic element  2214  can additionally have many shapes, including a helix shape, a spiral, a grid shape, a conical shape, zig-zag shape, non-coiled, and/or flat. Additionally, elastic element  2214  can be solid element, with no cut-away design, relying solely on the elasticity of the elastic element&#39;s  2214  material. 
     Rigid shaft  2202  can include a threaded end portion  2204 . The threaded end portion  2204  can be sized and shaped to fit within the hollow interior of insert  2210  and to engage with the threaded interior  2212  during the screwing motion. In some examples, the rigid shaft  2202  can have a wedge-lock feature or pattern  2000  configured to match a heel-interfacing surface  2216  of the top lift  120 ,  120 ′ (as discussed earlier with regards to  FIGS. 28-21 ). Therefore, these patterns  2000  and  2216  can be corresponding shapes such that when the insert  2210  receives the rigid shaft  2202 , the patterns  2000  and  2216  can engage each other. In some instances, when the threaded end portion  2204  is screwed into the insert  2210 , there can be one or more clicks when the patterns  2000  and  2216  engage each other. This provides a user with tactile and audible feedback to ensure that the insert has properly received the rigid shaft  2202 . Additionally, the patterns  2000  and  2216  can ensure perfect alignment between the rigid shaft  2202  and the insert  2210  such that the assembly as a whole aligns with a heel  114 ,  114 ′. 
     Therefore, a heel tip assembly  102 ,  102 ′, as shown by  FIGS. 22A-22D  provides a dual element assembly  102 ,  102 ′ which can be inserted by a user into a heel  114 ,  114 ′ with ease. This assembly has a small number of components which makes it a quick and easy product to provide additional structural support to a heel  114 ,  114 ′. When inserted into a heel  114 ,  114 ′ as described with respect to  FIGS. 22A-22D , the assembly can provide a unitary (one piece) element configured to provide structure, stability, and support to heel  114 ,  114 ′. The assembly therefore cannot be disassembled into its individual pieces without a user exerting a force to unscrew the rigid shaft  2202 ; the force exerted by the user needs to be stronger than the force exerted by the elastic portion  2214  that is pulling the rigid shaft  2202  back into the heel  114 ,  114 ′. 
       FIGS. 23A, 23B, 23C, and 24  show another exemplary heel tip assembly  102 ,  102 ′, according to another embodiment of the present disclosure. The assembly, as shown in  FIG. 24 , can include a heel tip  2310  ( FIG. 23A ), a shaft piece  2320  ( FIG. 23B ), and an elastic insert  2330  ( FIG. 23C ). All three components  2310 ,  2320 , and  2330  can be 3D-printed, constructed in a plastic mold, or any other similar process, without limitation. Components  2310 ,  2320 , and  2330  can be made of tire tread material, rubber, plastic, and metal, any combination thereof, and any similar material. Components  2310 ,  2320 , and  2330  can be made of the same or different materials. Generally, the elastic insert  2330  can be placed inside an opening in a heel which is a similar size to the elastic insert  2330 . The shaft piece  2320  can be screwed into the elastic insert  2330 . The heel tip  2310  can be placed onto the shaft piece  2320 . Therefore, the heel tip assembly as shown in  FIGS. 23A-23C and 24  can form a structural insert and sole for a high-heeled shoe. Additional features are discussed further below. 
       FIG. 23A  shows an exemplary heel tip  2310  which can include a cutout portion  2312 . The heel tip  2310  can be shaped to match a contour of the heel which heel tip  2310  is ultimately secured. The cutout portion  2312  can be sized and shaped to receive the shaft piece  2320 . The cutout portion  2312  can be a hexagonal shape, for example, although any other circular or polygonal shape is contemplated as well. The heel tip  2310  can be rotated when connecting to the shaft piece  2320  such that the heel tip  2310  aligns with the contour of the heel. 
       FIG. 23B  shows an exemplary shaft piece  2320  which can include a shaft head  2322 , a shaft body  2324 , and a threaded portion  2326 . The shaft head  2322  can be configured to match the shape and size of the cutout portion  2312  such that shaft head  2322  forms an interference fit with cutout portion  2312 . The heel tip  2310  can be put onto the shaft head  2322  by a user or installer. The threaded portion  2326  can be configured to match a threaded sleeve  2336  of the elastic insert  2330 . 
       FIG. 23C  shows the elastic insert  2330 , which can include a shaft portion  2332 , an elastic portion  2334 , and a threaded sleeve  2336 . The elastic insert  2330  can have a hollow interior with which to receive the shaft piece  2320 . The shaft portion  2332  can protect the shaft piece  2320 , as it is received by the elastic insert  2330 , from rubbing against a heel in which the elastic insert  2330  is inserted. The threaded sleeve  2336  can receive the threaded portion  2326  of the shaft piece  2320 . While the shaft piece  2320  is screwing into the threaded sleeve  2336 , the elastic portion  2334  can be compressed and rotated. The elastic portion  2334  can provide a resultant force pulling the shaft piece  2320  deeper into the hollow interior of the elastic insert  2330 . The interference fit between the elastic insert  2330  and the heel can prevent the elastic insert  2330  from rotating to relieve the elastic force caused by the shaft piece  2320 . In some examples, an adhesive element can be placed on the exterior of the elastic insert  2330  before it is inserted into a heel to further prevent the elastic insert  2330  from rotating. 
     Elastic portion  2334  can be a variety of shapes and sizes although only one shape and size is demonstrated in  FIGS. 23C-24 . The elastic portion  2334  can shaped as a spiral, a spring, a grid shape, an off-center grid, or a lattice or lattice-like structure. The elastic portion  2334  can have cutaway portions in the shape of rectangles (as shown in  FIG. 23C ), ovals, helices, spirals, honeycomb, or any other cutaway form. Elastic portion  2334  can have a regular and symmetrical shape (as shown in  FIG. 23C ), or an irregular, a symmetrical shape (e.g., a spiral where top portions of the spiral are more spaced out than lower portions). In some cases, elastic portion  2334  can be solitary curved lines rising from the shaft portion  2332  to the curved portion  2336 . Design shapes can be chosen according to weight, material, and elasticity concerns. Elastic portion  2334  can further include all the non-limiting exemplary embodiments as discussed with respect to elastic element  2214  of  FIGS. 22A-22C . The elastic portion  2334  preferably has a regular, repeating pattern or shape so that the elastic portion  2334  compresses or expands uniformly about a cross section thereof without breaking or crushing any vertical members or elements of the pattern or shape that provides or imparts the elasticity or springiness to the elastic portion  2334 . The design or pattern of the elastic portion  2334  can be selected based on suitability for being made according to 3D printing methods. The entire insert  2330  together with the elastic portion  2334  shown in  FIG. 23C  can be a unitary, one-piece integral structure, for example, constructed according to a 3D printing method. The elastic portion  2334  can have a lattice-like pattern having compressible members that can be restored to a pre-compressed state without being crushed or broken. 
       FIG. 24  demonstrates how the three pieces, as shown individually in  FIGS. 23A-23C  can cooperate to provide structure, stability, and support to a heel  114 ,  114 ′ when the elements are assembled. The assembly cannot be disassembled into its individual pieces without a user removing the heel tip  2310  and exerting a force to unscrew the shaft piece  2320  from the elastic insert  2330 ; the force exerted by the user needs to be stronger than the force exerted by the elastic portion  2334  that is pulling the shaft piece  2320  back into the heel  114 ,  114 ′. 
     Any of the top lifts disclosed herein can be used in connection with any of the heels, and any anti-rotation feature can be combined with any alignment feature and/or any securing feature and/or any cushioning feature disclosed herein. It is seen that the combination of these features contributes to the overall stability, wearer comfort, noise suppression, longevity, customizability or interchangeability, facile and expedient construction and manufacturability, and repairability or serviceability, to name a few benefits, of the high heel footwear, particularly over prolonged usage. The honeycomb pattern provides a cushioning effect, a tire tread top (facing the ground) provides a grip or anti-slipping feature while also suppressing the sound the heel makes when contacting a ground surface, such as a polished floor or tile, the various securing features provide a secure way of interfacing the top to the heel, sometimes in a way that is reversible, and the alignment features ensure that the outer contour of the top lift and heel at their interface match so that no visual artifacts are perceived. The alignment should be made blindly so that the manufacturer or installer can quickly secure the top lift to the heel without having to make minor adjustments to ensure co-alignment. The alignment feature also stands up to prolonged wear and tear over time, ensuring that the top lift and heel remain aligned. The anti-rotation features disclosed herein prevent rotation of the top lift relative to heel, which prevent twisting moments and misalignment of the top lift relative to the heel over prolonged use. The various materials used, such as tire tread material, rubber, plastic, and metal, can be interfaced together securely or permanently by adhesive or any other technique for interfacing such materials to metal. The embodiments of  FIGS. 18-24  provide a do-it-yourself assembly that allows the wearer of the footwear to retrofit an existing footwear with a replaceable heel tip that can be secured to the heel and then removed easily and replaced with a new one. Alternately, the heel of the footwear can be adapted by the manufacturer to include the internal components described above in connection with  FIGS. 18-19 and 23B-23C , and then the wearer can readily replace him- or herself the heel tip with a new one by simply unscrewing and removing the old one and installing a new one merely by screwing the new one in with absolutely no tools required. 
     The above description only provides an explanation of the preferred embodiments of the present disclosure and the technical principles used. It should be appreciated by those skilled in the art that the inventive scope of the present disclosure is not limited to the technical solutions formed by the particular combinations of the above-described technical features. The inventive scope should also cover other technical solutions formed by any combinations of the above-described technical features or equivalent features thereof without departing from the concept of the disclosure. Technical schemes formed by the above-described features being interchanged with, but not limited to, technical features with similar functions disclosed in the present disclosure are examples.