Patent Application
20240325864
This invention relates to the toe unit of release bindings used in alpine ski touring, also known as “AT bindings”. More particularly, this invention relates to such heel units which engage with the footwear for skiing and support the heel with adjustable risers for ski touring.
Alpine touring bindings allow the heel of the user's footwear (such as a ski boot) to be latched to a snow travel aid (such as a ski), for sliding downhill (the “downhill mode”) and allow the heel to be released for walking and climbing (the “touring mode”). Release bindings allow the footwear to release from the snow travel aid when in the downhill mode, in case of a fall. When in the touring mode, the user may climb or walk with a great degree of freedom since the footwear is pivotally engaged with the aid near the toe of the footwear while the heel of the footwear is free to move upward and downward relative to the aid. A historical collection of such bindings can be viewed in the “Virtual Museum of Backcountry Skiing Bindings” at www.wildsnow.com, authored by Louis Dawson.
Alpine touring bindings that take advantage of the fact that modern alpine touring boots have a rigid sole are called “pin bindings”. With pin bindings it is unnecessary to provide a bar, plate or other arrangement connecting the toe and heel units, as is the case with many other alpine touring bindings (see patent publications EP0199098, EP0519243, EP1559457, and AT402020). Unlike other release bindings, lateral release of pin bindings is provided at the heel, not the toe.
Pin binding systems comprises a toe unit which has a set of jaws that pivotally engage a special insert in the footwear sole. The toe unit is mountable at an appropriate location on the upper surface of a snow travel aid. A separate heel unit is mountable at a particular region on the upper surface rearward of the toe unit, the location of which is dictated by the length of the footwear sole. The toe and heel units function independently in retaining the footwear attached to the snow travel aid. The heel unit comprises projections (typically a pair of pins) which extend forward to engage opposite sides of a fitting placed over a cavity in the rear of the footwear heel. Under forward release conditions, the pins are intended to be forced apart against spring pressure to respective release positions to disengage from the fitting and the heel. The pins typically communicate with a spring or springs through inclined sliding surfaces that move a block which engages the spring or springs. The original method of creating the spring pressure for the pins is to embody the two pins in a singular u-shaped spring, examples of which can be seen in EP0199098, DE202015005560, EP3050602 and EP4112140. Bindings of this type that make use of a u-shaped spring will be called “u-spring bindings.” They typically work by having the u-spring handle the forward falling portion of release which retains the footwear heel vertically when skiing, while the lateral or twist release portion of the release is handled by one or more springs that are either horizontally mounted springs (EP0199098 and DE202015005560) or vertically mounted springs (EP3050602 and EP4112140). In both of the aforementioned binding types the springs providing the lateral release biasing action both push on a plunger which slides against a cam surface to provide this biasing action.
U.S. Pat. No. 10,010,782 describes a u-spring type pin binding where the u-spring biases the heel for both the forward falling and the lateral release modes. When twisting the heel unit about a vertical axis, two vertically mounted pins force the u-spring to open, which biases the heel unit towards a central skiing position.
The main advantage of the “u-spring” bindings is that they are mechanically simple, lightweight and inexpensive to manufacture. They are popular with dedicated ski tourers and ski mountaineers who seek to find a binding with the most minimal weight. U-spring bindings have the disadvantages of being set for only a single release value and they are subject to wear since the heel fittings rub the u-spring ends under high load with every engagement and vertical release of footwear for skiing. This results in a binding that is not possible to adjust the release forces to recommended values for based on the skier's size and weight without disassembling the binding, and switching out the u-spring for one with a different opening stiffness. Since many of the skiers who use these bindings are more interested in saving weight than the safety function of the bindings, they typically make this compromise.
U.S. Pat. No. 10,463,946 describes a binding where the u-spring is replaced by two independent pins that are able to rotate about their long axis and are biased against opening under the force of the footwear heel insert by a set of springs. This design allows the release value to be adjusted by means of adjusting the preload of the springs, and it also prevents the wear mentioned above that's associated with the u-spring bindings since the heel pins can rotate when the footwear heel is engaged with the binding, which prevents sliding wear under high load. The disadvantage of this type of binding is that it is much more complex, involves more moving parts, and is significantly heavier than u-spring bindings.
One attempt to make u-spring bindings adjustable has been shown in the KREUZSPITZE GT 2.0 binding (described here https://www.wildsnow.com/33339/kreuzspitze-gt-2-0-binding-a-first-look/), whose mechanism also appears to be present in EP3906980. The heel pin ends that engage with the footwear are cylindrical pins with holes inside them, and a u-spring element whose position can be adjusted fore and aft is inserted into the rear end of each heel pin. This provides a simple u-spring style binding that has adjustable release by way of changing the mechanical advantage of the u-spring by adjusting its position relative to heel pins. The disadvantage of this system is that the heel pins tips need to be retained inside the heel unit so they do not slip fore and aft but can move side to side.
Given the above summarized state of the art, one object of the present invention is to make lightweight ski binding heel units release settings easily adjustable.
Another object of the present invention is to make lightweight ski binding heel units heel pins more durable than u-spring bindings.
Another object of the present invention is to provide a means of making u-spring bindings designs adjustable and more durable by swapping out the u-spring for two separate heel pins with a means of adjusting an effective spring action of those pins.
Among preferred embodiments of this invention are novel design elements that, alone or in combination may denote, or contribute to, fulfillment of one or more of the foregoing objects of the invention, and in doing so, individually or collectively achieve an improved ski binding heel unit that is simple to manufacture, lightweight, has adjustable release settings, and is more durable that u-spring bindings. In one particularly beneficial embodiment of the present invention, a ski binding heel unit for a pin binding has two independent heel pins that are rotatable along their long axis, and are held at the appropriate width for engaging the footwear heel fitting by a blocking element located at a variable position along the length of the heel pins, which position can be adjusted fore and aft by way of an adjustment, such as an adjustment screw. The rear ends of the heel pins are fixed pivotally to allow rotation along their long axis as well as lateral rotation about a vertical axis, but restrained against longitudinal or lateral displacement. When the heel fitting is forced in-between the two heel pins, the heel pins themselves provide a biasing by each flexing outward at the frontmost heel pin tip, while being laterally restrained at the width of the blocking element. By adjusting the position of the blocking element towards the front of the binding unit, the release value will increase due to the shortening of the flexible front region of the heel pin, denoting a stiffening of the effective spring cooperatively embodied by the two pins. Conversely, if the blocking element is adjusted towards the rear of the heel unit, it softens the heel pin opening force due to the longer flexible front region and the increase in mechanical advantage. The blocking element only prevents the heel pins from opening (spreading) outwardly at the location of the blocking element, without detriment to a freely rotatable character of the pins along their long axes in their passage through the blocking element. The advantageous design is lightweight and simple, yet adjustable and durable. It's possible to utilize an arrangement like this to replace the “u-spring” in heel units that previously utilized such u-springs.
According to one aspect of the invention, there is provided a heel unit apparatus for a ski touring binding, the apparatus comprising:
According to another aspect of the invention, there is provided a heel unit apparatus for a ski touring binding, the apparatus comprising:
The above and other objects, aspects, features and advantages of the invention will become apparent from a consideration of the subsequent detailed description presented in connection with the accompanying drawings.
The accompanying drawings, which are incorporated in and constitute part of this disclosure, illustrate exemplary aspects that, together with the written descriptions, serve to explain the principles of this disclosure. Numerous aspects are particularly described, pointed out, and taught in the written descriptions. Some structural and operational aspects may be even better understood by referencing the written portions together with the accompanying drawings, of which:
Aspects of the present disclosure are not limited to the exemplary structural details and component arrangements described in this description and shown in the accompanying drawings. Many aspects of this disclosure may be applicable to other aspects and/or capable of being practiced or carried out in various variants of use, including the examples described herein.
Throughout the written descriptions, specific details are set forth in order to provide a more thorough understanding to persons of ordinary skill in the art. For convenience and ease of description, some well-known elements may be described conceptually to avoid unnecessarily obscuring the focus of this disclosure. In this regard, the written descriptions and accompanying drawings should be interpreted as illustrative rather than restrictive, enabling rather than limiting.
In known fashion, the inventive heel unit 24 features a chassis 34 for flush placement atop a ski 100 and fastening of the heel unit hereto via mounting screws 36 tightenable through suitably located fastening holes of the chassis 34. A static heel post 38 stands vertically upright from the chassis 34 to accommodate mounting thereover of a heel body 40 that can be rotatably adjusted about a vertical axis of the heel post 38. Referring to
The heel body 40 has a lower front cylindrical hub 44 characterized by an internal cylindrical bore of downwardly open character by which the heel body is rotatably mountable over the heel post 38. A tail 46 of the heel body 40 radiates unidirectionally from the hub 44 in the rearward longitudinal direction. Situated atop the hub 44 and across from the tail 46 is a head 48 of the heel body 40 that spans laterally across the heel body 40 in tangential relation to the cylindrical shape of the hub 44. Laterally opposing sides of the head 48 are characterized by respective notches 50 of laterally open character, each of which cradles a respective one of the heel pins 26. From each notch 50, the front region 26A of the respective heel pin 26 projects forwardly past the head 50 to overhang from the front end of the heel body 40 in exposed fashion engageable by the footwear heel fitting 16. Also atop the hub 44, at a position diametrically across the from the head 50 and above the tail 46, the heel body 40 features a pivot lug 52 penetrated by a threaded longitudinal pivot bore 52A that aligns with a blind hole in rear face of the head 48 to accommodate cooperative support of a heel lift pivot 54 in the pivot bore 52A and aligned hole in the rear of the head 48. The heel lift pivot 54 thus spans longitudinally and diametrically across the hub 44 in elevated relation thereover. An externally threaded pivot retainer 54A is engaged in the threaded pivot bore 52A behind the heel lift pivot 54 to capture the heel pivot 54 in its installed position, thereby locking it to the heel body 40. A pair of heel lifts 56 are pivotally supported on the heel lift pivot 54 for pivotal movement thereabout. In touring mode, when the heel body is rotated 90-degrees from its illustrated downhill mode position, one or both heel lifts 56 can be situated in working positions overhanging forwardly from the heel post 38 (at the front position that is occupied by the overhanging front regions 26A of the heel pins 26 in the illustrated downhill mode). Here, the heel lifts 56 can be used by the skier to support the bottom of the footwear heel while climbing slopes. If not needed, one or both heel lifts can be flipped to a reversed non-working position to the rear of the heel post 38, thus out the way of the skier's footwear.
Restraint of the rear regions 26C of the heel pins 26 is achieved by the rear pivots 32 and a heel cap 58 that are cooperatively installed atop a rear mount 60 of the heel body 40 that resides at or near a rear end of the tail 46 furthest from the hub 44. The vertically oriented rear pivots 32 are threaded downwardly into threaded holes in the rear mount 60 through matching holes in the heel cap 58, whereby the rear pivots 32 perform double duty to both fasten the heel cap 58 in place and serve as bearing surfaces that restrain the rear regions of the heel pins 26 against laterally inward displacement. The rear mount 60 and the heel cap 58 fastened thereto cooperatively form a pair of pin-receiving channels, each of which houses the rear region 26C of a respective one of the heel pins 26. The rear region 26C of each heel pin 26 is thereby vertically bound between the heel cap 58 and the underlying rear mount 60, and horizontally bound between an outer side of the channel (e.g. embodied by a downturned outer wall of the heel cap 58 in the illustrated example, or alternatively by an upturned outer wall of the rear mount 60 in an unillustrated variant) and the respective rear pivot 32 that resides at an opposing inner side of the channel. The rear pivots 32 and the cooperating heel cap 58 and rear mount 60 thus collectively form a rear heel pin restraint by which the rear regions 26C of the heel pins 26 are restrained against longitudinal, lateral and vertical displacement.
The rear region 26C of each heel pin 26 of the illustrated embodiment is characterized by a circumferential groove 62 of concavely rounded character, which groove is matched to the respective rear pivot 32, which in this embodiment is a pivot pin whose cylindrical profile has an outer arc thereof received in the rounded groove so that the rear pivot 32 restricts longitudinal movement of the heel pin 5 in the forward and rearward directions, but allows the heel pin 26 to spin about its longitudinal axis. As revealed in
The heel pin blocker 28 lies laterally across the tail 46 of the heel body 40 at a position elevated thereover between the rear mount 60 and the pivot lug 52, and has a threaded center bore 28A penetrating longitudinally therethrough, and two pin channels 28B penetrating longitudinally therethrough on respective sides of the center bore 28A. The blocker adjustment screw 30 engages into the threaded center bore 28A of the heel pin blocker 28 through a rear center opening delimited between the heel cap 58 and rear mount 60 at a position between the two pin-receiving channels. An actuation head 30A of the adjustment screw 30 projects through, or is at least accessible in, the rear center opening, and a threaded shaft 30B of the adjustment screw 30 spans forwardly from the head 30A to the pivot lug 52 and has its threads engaged with those of the threaded center bore 28A of the heel pin blocker. User rotation of the adjustment screw 30 is operable to longitudinally advance and retreat the heel pin blocker 28 along the threaded shaft 30B of the adjustment screw 30 in the confined space between the pivot lug 52 and the heel cap 58, thereby adjusting the particular location along the heel pins 26 at which the heel pin blocker 28 encompasses the heel pins 26 and restrains the same against laterally outward deflection at an outside wall of each pin channel 28B. As best shown in
In alternative to inclusion of a circumferential groove 62 in each heel pin 26 at the captured rear region 26C thereof to cooperate with a respective cylindrical rear pivot 32 in a manner blocking longitudinal displacement of the pin 26 while allowing rotation thereof via receipt of the cylindrical pivot profile in the rounded concavity of the groove 62, a variant of the illustrated embodiment could instead embody a spherical ball at the rear end of the heel pin 26 cooperating with a spherical socket inside the respective channel of the rear mount 60 and heel cap 58, in similar fashion to such ball tipped pins seen in aforementioned U.S. Pat. No. 10,463,946. The heel pin 5 diameter can also be varied along its length, as variation in the pin diameter will affect the spring characteristics of the pin and vary the degree of adjustment of that occurs during graduated advancement and retraction of the blocker back and forth along the pins. Pins with differential variable profiles can also be offered to provide different spreading force characteristics that allow different ranges of release values for skiers of different sizes. In this way we can turn a typical u-spring binding that's not adjustable or durable into a binding where the user doesn't have to make these compromises with adding very little weight by not requiring a coil spring.
A lateral release mechanism that's well known in the prior art can be implemented, and utilizes a lateral release spring 64, a lateral release plunger 66 and a lateral release adjuster 68, by which the heel pins 26 are biased, in the manner described in more detail below, towards a central position pointing forwardly and lying symmetrically of the ski's longitudinal midline axis 42. In this embodiment, the heel pins 26 themselves can resist loads in the lateral direction that arise from the skier twisting their leg about a vertical axis, and thus don't spread under such action, and it is the lateral release spring 64 that will instead give way under such instances. The lateral release components 64, 66, 68 are housed in the heel body 40, which as previously mentioned, is able to rotate about a vertical axis defined by the heel post 38. More particularly, in order of proximity to the heel post 38, the lateral release plunger 66, the lateral release spring 64 and the lateral release adjuster 68 are cooperatively installed within a longitudinally oriented internal bore of the tail 46 of the heel body 40, a front end of which bore opens horizontally into the vertically oriented internal bore of the hub 44. The heel body 40 is restrained vertically to the heel post 38 by a top hat spacer 70 and a heel body screw 72. A crown of the top hat spacer 70 is rotationally locked into the heel body 40 at the ceiling of the hub's internal bore, and the rim of the top hot spacer slides against a ceiling of a hollow interior of the post 38 so that the heel body screw 13 will not loosen. The heel post 38 has three detents of rounded camming profile in its periphery, situated at ninety degrees to one another around the vertical heel post axis, with one detent at the rear and two slots at laterally opposing sides. Spring biased engagement of the lateral release plunger 66 in the rear detent of the heel post 38 holds the heel body 40 in the illustrated downhill mode position, with the heel pins 26 protruding forwardly from the heel post 38 in a centered position. Lateral release adjuster 68 is threaded in the longitudinal bore of the tail 46 of the heel body 40, whereby rotation of the adjuster 68 is operable to adjust the pre-compression of the lateral release spring 64, and thereby control the lateral release force by which the heel body 40 is biased to the centered position by the cooperatively camming profiles of the post's rear detent and the mating plunger 66.
As mentioned above, the rear detent in the heel post 38 is accompanied by two side detents situated at ninety degrees from the rear detent, from which it will be appreciated that this embodiment is switchable to the touring mode by rotating the heel body 40 from its longitudinally oriented downhill mode position parallel to the longitudinal travel direction, as shown in the drawings, to either one of two possible touring mode positions each oriented perpendicular to the longitudinal travel direction. In either touring mode position, the plunger 66 is relocated to one of the side detents in the heel post 38, in which the spring biased plunger 66 achieves a relatively stable static or solid position. In such touring mode positions, the heel pins 26 point laterally outward from the heel post 38 at one side thereof instead of pointing forwardly therefrom, and one or both heel lifts 56 can be positioned about the heel lift pivot 54 into the working position at the front of the heel post 38 for optional use to support the bottom of the footwear heel while climbing slopes.
The chassis 34 of the heel post 38 can be mounted directly to a ski by the mounting screws 36, or indirectly into an adjustment plate to allow the heel unit position to be adjustable fore and aft of the ski 100 to fit different size footwear. It should be noted that the arrangement of components 26, 28 and 30 could be used with a binding of the type shown in U.S. Pat. No. 10,010,782, and instead of the heel pins 26 just biasing the forward falling release force, with separate reliance made on lateral release spring 64 to bias the lateral release force, the heel pins 26 could instead be reconfigured in a manner responsible for biasing both the forward falling and lateral release forces, in similar fashion to how the binding of U.S. Pat. No. 10,010,782 uses its u-spring 10 to control lateral release. This would be a significant improvement over the prior art, since it would have a single adjustment screw 30 for both release modes. This would mean that binding setup would be extremely quick, release loads would be appropriate for every user, and the heel pins 26 would be much more durable than a u-spring binding.
One possible implementation of such an alternate embodiment of the heel unit 24′ is schematically illustrated in
While principles of the present disclosure are described herein with reference to illustrative aspects for particular applications, the disclosure is not limited thereto. Those having ordinary skill in the art and access to the teachings provided herein will recognize additional modifications, applications, aspects, and substitution of equivalents all fall in the scope of the aspects described herein. Accordingly, the present disclosure is not to be considered as limited by the foregoing description.
This application claims benefit under 35 U.S.C. 119 (e) of U.S. Provisional Patent Application No. 63/456,466, filed Apr. 1, 2023, the entirety of which is incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| 63456466 | Apr 2023 | US |
