Patent Description:
The present description relates generally to a fastener system designed to clamp two structures.

<CIT> describes a screw with a sleeve cylinder portion to which a male screw portion of the screw is screwed. The sleeve has a notch so that a pair of claw portions of a spring can protrude in an outer radial direction.

<CIT> describes an expandable collet anchor system incorporating means for fastening at least two objects, each having a generally circular aperture, together to form a structural or a non-structural attachment.

<CIT> describes an expandable collet anchor systems with captive studs.

Many manufacturing fields use fasteners, such as blind fasteners, for securing two objects to one another. Blind fasteners are particularly useful when only one side of a joint is accessible. One application of such fasteners is in the aerospace industry where removable collet fasteners are utilized to secure floor panels to underlying floor beams. Using removable fasteners to secure floor panels to the floor beams increases the modularity of the aircraft's cabin. Resultantly, the aircraft's interior may be altered at a late stage in manufacturing to increase the adaptability of aircraft manufacturing processes. Therefore, the manufacturer or in some cases the customer may alter the floor panel layout to reconfigure the airplane when desired. In other examples, the collet fasteners may be used to attach wing components, fuselage components, pylons, etc., providing the same benefits of increased manufacturing adaptability. Previous blind fasteners have included a stud threading into a collet body having fingers that radially expand when said threading occurs. When expanded the fingers slide under a lower structure to act as a lower clamping arm while a surface of the stud head acts as an upper clamping arm to retain an upper structure.

However, the inventors have recognized several drawbacks with previous blind fasteners. For instance, the collet body may be susceptible to shear stresses due to external structural loading and the external position of the collet body in the fastener. The collet body contains multiple flexible arms that, as a necessity of the prior fasteners, operate independently from one another. As such, they are disjointed and do not communally share shear strength with one another. When in shear, only the flexible arms directly in contact with the load path can resist the shearing force. In the previous fasteners, the flexible arms are tangentially positioned at a maximum distance from a line created by the intersection of the shear force vector acting through the center of the collet body. These flexible arms resist very little, if any, of the shearing force. As a result, individual flexible legs in prior fasteners can become substantially damaged and fail, or suffer other forms of damage (e.g., permanent deformation) that impede desired functions of the flexible legs. The stud may be difficult to remove and in some cases become stuck within the collet body when the fastener clamps two adjoining structures. Furthermore, the fingers in the collet body may be difficult to insert into a bore due to the exposed edges of the collet body fingers now deformed and protruding radially outward, due to damage sustained in resisting shear.

Facing the aforementioned challenges the inventors developed a fastener system. The fastener system includes a sleeve with a sleeve opening and a collet body at least partially enclosed within the sleeve, the collet body including a crown having a crown opening, and a cantilever leg extending from the crown and including a foot configured to mate with the sleeve opening when the fastener system is in an engaged configuration. The fastener system also includes a stud extending or extendable through the crown opening and includes a threaded section engaging or engageable with an interior threaded section in at least one of the collet body and/or the sleeve. In this way, the cantilever leg may be protected by the collet body and shear stresses on the cantilever leg may be decoupled from the collet body while the system exerts a clamping force on two structures. In particular, the sleeve protects the collet body from shear stresses across the flexing part of the cantilever leg created from sideways forces in the structures that are being fastened. Thus, the longevity of the fastener described herein, when compared to previous fasteners that suffer from shear stresses degrading the ability of the cantilever leg to flex or retain its memory shape, can be increased. Moreover, the fastener also allows the stud to be easily threaded and unthreaded without binding, enabling the system to be easily and efficiently installed as well as removed. Moreover, when the collet body is constructed out of a nonmetallic material, such as a polymer, the sleeve protects the collet body from abrasive wear during insertion and removal, decreasing the likelihood of fastener degradation.

In one example, advancing engagement between the threaded section of the stud and the interior threaded section decreases a distance between an upper clamping surface and a lower clamping surface, the lower clamping surface is included in the foot and the upper clamping surface is included in the stud. In this way, the clamping force generated by the fastener system can be varied to provide a desired amount of coupling between two components while the shear stresses are, to a large extent, uncoupled from the collet body.

In another example, the stud may include a reduced diameter section (e.g., unthreaded section) positioned near a bushing engagement zone. The reduced diameter section is configured to allow the stud to freely spin when the stud is unthreaded and disengaged from the interior threaded section. Allowing the free rotation of the stud in this manner prevents the stud from damaging the sleeve or collet body during disengagement.

In another example, the fastener system may include an auxiliary structure at least partially extending around the sleeve and including a lower surface acting as a lower clamping surface. The auxiliary structure enables quick and efficient removal of the system after it is unclamped and also may require less machining of the bores in the clamped structures. In this way, the fastener system may be utilized in a broader range of structures.

It should be understood that the summary above is provided to introduce in simplified form a selection of concepts that are further described in the detailed description. It is not meant to identify key or essential features of the claimed subject matter, the scope of which is defined uniquely by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure.

The following description relates a fastener system designed to decouple shear stresses from a collet body and provide clamping engagement to targeted structures. Decoupling of the shear stresses from the collet body enables quick, efficient, and unobstructed engagement and disengagement of clamping arms in the system. In particular, the fastener system is designed to decouple shear forces from a weaker section (i.e., cantilever legs) and place the same shear forces onto a much stronger section (i.e., a sleeve). As a result, the fastener system has excess capacity, enabling the system to carry additional shear forces. The fastener system includes a collet body that fits within a sleeve. The collet body is provided with feet on the end of cantilever legs extending downward from a crown. When the fastener system is in an engaged configuration and a stud is threaded into the collet body and sleeve, the feet protrude through openings in the sleeve. The sleeve protects the collet body and prevents shearing forces from acting on the collet body while allowing the feet to function as lower clamping arms. An underside of the head of the stud or an auxiliary structure surrounding the sleeve may act as an upper clamping arm. As the stud is further threaded into the collet body and sleeve, a distance between the feet and a head of the stud decreases. In this way, the clamping force generated by the fastener system can be varied to provide a desired amount of engagement between two structures. The stud may also include an unthreaded section at one end. The unthreaded section is designed to enable free rotation of the stud with regard to the sleeve and collet body when the stud is disengaged (e.g., fully backed out) from an interior threaded section in the sleeve or collet body. Consequently, the stud may be prevented from damaging the sleeve or collet body during disengagement (e.g., maximum disengagement).

<FIG> show a first example of a fastener system. <FIG> show the first example of the fastener system with a retainer functioning to securely retain a collet body in a sleeve. <FIG> show an engagement sequence where the fastener system engages with structures. <FIG> show a second example of a fastener system where the collet body includes a threaded section designed to engage with threads in the stud. <FIG> show a third example of the fastener system including an auxiliary structure. <FIG> shows a fourth example of the fastener system again including an auxiliary structure. <FIG> show a fifth example of the fastener system where the auxiliary structure includes an upper threaded section. <FIG> shows a sixth example of the fastener system including a collet body with a pair of cantilever legs designed to mate with a pair of openings in a sleeve. <FIG> shows a seventh example of the fastener system including a stud with a free-spin zone and an auxiliary structure. <FIG> show an eighth example of the fastener system including a retaining ring and a stud including an increased diameter threaded portion. <FIG> show an engagement sequence in a fastener system. <FIG> show a ninth example of a fastener system. <FIG> show a tenth example of the fastener system including a split collet body. <FIG> shows a method for operation of a fastener system to assemble the fastener and then clamp and unclamp the fastener from structures.

Turning to <FIG>, an exploded view of a fastener system <NUM> is illustrated. The fastener system <NUM> includes a stud <NUM>, a sleeve <NUM>, a collet body <NUM>, and a bushing <NUM>. Each of the components in the fastener system <NUM> share a common central axis <NUM>.

The stud <NUM> includes a first end <NUM> and a second end <NUM>. A head <NUM> is included in the first end <NUM>. The head includes a tool interface <NUM>. In the illustrated example, the tool interface <NUM> is a splined recess. However, other suitable types of interfaces have been contemplated such as hexagonal recesses, slotted recesses (e.g., a Phillips type recess), a square recesses, external spine or hex for use with conventional sockets, etc. The tool interface <NUM> is designed to receive a driver (e.g., splined driver, hexagonal driver, etc.,) inducing rotation (e.g., clockwise or counterclockwise rotation) of the stud <NUM> about the central axis <NUM>.

The head includes an upper surface <NUM>. In the illustrated example, the upper surface <NUM> is planar. However, other contours of the upper surface of the head have been contemplated. The stud <NUM> further includes a threaded section <NUM>, a first reduced diameter section <NUM>, and a second reduced diameter section <NUM> (e.g., bushing engagement zone). In the depicted example, the first reduced diameter section is unthreaded. However, in other examples, at least a portion of the first reduced diameter portion may be threaded.

The second reduced diameter section <NUM> is configured to mate with the bushing <NUM> at the second end <NUM> of the stud <NUM>. As illustrated, the second reduced diameter section <NUM> has a cylindrical shape with an outer diameter <NUM> that is less than an outer diameter <NUM> of the first reduced diameter section <NUM>. However, other contours of the second reduced diameter section <NUM> have been contemplated. Additionally, an outer diameter <NUM> of the threaded section <NUM> is greater than the outer diameter <NUM> of the first reduced diameter section <NUM>, in the illustrated example. In this way, the second end <NUM> of the stud <NUM> may travel through a central aperture <NUM> in the sleeve <NUM> and a crown opening <NUM> in a crown <NUM> of the collet body <NUM>.

The sleeve <NUM> includes a first end <NUM> and a second end <NUM>. The first end <NUM> includes a facetted collar <NUM>. The facetted collar <NUM> includes planar surfaces <NUM>. In the depicted example, the planar surfaces <NUM> form a hexagonal shape. However, numerous shapes have been contemplated. Such as square shapes, pentagonal shapes, octagonal shapes, etc. Furthermore, the collar may include lobes or other protrusions that are not planar, in other examples. The surfaces on the collar, being planar or nonplanar, are configured to limit (e.g., substantially inhibit) rotation of the sleeve <NUM> while allowing axial translation during installation and removal of the fastener system. The facetted collar <NUM> may be mated with a bore in a structure, having a corresponding geometry (e.g., hexagonal shape) to limit (e.g., substantially inhibit) rotational movement about axis <NUM> of the sleeve <NUM> and therefore collet body <NUM> while the stud <NUM> is rotated or vice-versa and correspondingly facilitates axial translation of the sleeve. However, in other examples, the facetted collar <NUM> may be gripped by a tool, held by a tool body, or held by an auxiliary structure to inhibit movement of the sleeve <NUM> while the stud <NUM> is rotated while allowing axial translation of the sleeve.

The sleeve <NUM> further includes an interior threaded section <NUM>. The interior threaded section <NUM> in the sleeve <NUM> is designed to engage with the threaded section <NUM> in the stud <NUM> when the stud is inserted into the central aperture <NUM> and rotated to initiate engagement.

The sleeve <NUM> also includes opening <NUM> (e.g., sleeve openings) configured to mate with feet <NUM> in the collet body <NUM>, discussed in greater detail herein. Additionally, the openings <NUM> include an upper side <NUM>, lower side <NUM>, and lateral sides <NUM>. The sides of the openings limit (e.g., substantially inhibit) rotational movement about axis <NUM> of the feet <NUM>, when the collet body <NUM> is mated with the sleeve <NUM>. Furthermore, the openings <NUM> radially extend outward through a housing <NUM> of the sleeve <NUM>. Additionally, the openings <NUM> are equally spaced around the housing <NUM>, in the illustrated example. However, unequal spacing of the openings has been contemplated. Additionally, the fastener system <NUM> includes a corresponding number of openings <NUM> in the sleeve <NUM> and feet <NUM> in the collet body <NUM>. However, the fastener system <NUM> may include a mismatched number of feet and openings, in other examples. Furthermore, the fastener system <NUM> includes three openings and three feet, in the illustrated embodiment. However, alternate numbers of feet and/or openings have been envisioned.

The collet body <NUM> includes cantilever legs <NUM> extending in an axially downward direction <NUM> from the crown <NUM>. As referred to herein an axially downward direction is an axial direction extending toward the bushing <NUM> or other lower end system components while an axially upward direction <NUM> is an axial direction extending toward the head <NUM> of the stud <NUM> or other upper end system components. An exemplary radial axis <NUM> is also provided for reference. It will be appreciated that the central axis <NUM> may be parallel to a gravitational axis, in some examples. However, in other examples, alternative orientations of the central axis have been contemplated. The cantilever legs <NUM> are configured to act as springs and generate return forces in response to radial bending in both inward and outward directions. However, in <FIG>, the cantilever legs <NUM> are in a neutral position. In one example, the cantilever legs <NUM> may be pre-bent and/or heat-treated to enable the legs to achieve the neutral position, shown in <FIG>. The heat-treating may also increase the spring action in the legs. It will also be appreciated that the cantilever legs <NUM> will return to their neutral states after being deformed (e.g., bent inward and outward). In other examples, the cantilever legs <NUM> may be in a neutral state when the fastener system is in the engaged configuration, such as when the fastener system is constructed out of a polymer.

As depicted, the cantilever legs <NUM> are spaced away from each other such that gaps <NUM> are formed there between. The cantilever legs <NUM> include feet <NUM> protruding radially outward from lower end and outer sections of the cantilever legs <NUM>. The feet <NUM> are contoured to mate with the openings <NUM> in the sleeve <NUM>. Specifically, the feet <NUM> each include an upper surface <NUM>, side surfaces <NUM>, a peripheral surface <NUM>, and a lower surface <NUM>, in the illustrated example.

The cantilever legs <NUM> additionally include a hinge zone <NUM>. The hinge zone <NUM> may be formed naturally or enhanced adjacent to where the cantilever legs <NUM> join to crown <NUM> of collet body <NUM>. This hinge zone <NUM> enables the cantilever legs to flexibly swing in an arc during radial loading and unloading. In one example, the hinge zone <NUM> may include a tapered section (e.g., radially tapered section) that facilitates leg flexion.

The collet body crown <NUM> includes the crown opening <NUM> having an inner diameter <NUM> that is greater than an outer diameter <NUM> of the threaded section <NUM> of the stud <NUM>. In this way, the crown opening <NUM> is sized to receive the stud <NUM>. Additionally, the crown has an annular shape, in the illustrated example. However, alternative crown contours have been contemplated. Furthermore, the crown opening is sized to receive the bushing <NUM>, in the depicted example. That is to say, that an outer diameter <NUM> of the bushing <NUM> is smaller than the inner diameter of the crown opening <NUM>. However in other instances, the crown <NUM> may be sized to retain the bushing <NUM> such that the inner diameter <NUM> of the crown opening <NUM> is less than the outer diameter <NUM> of the bushing <NUM>. As such, the crown may be configured to limit axial movement of the stud <NUM>. Additionally, the central aperture <NUM> in the sleeve <NUM> has a smaller diameter <NUM> than the outer diameter <NUM> of the bushing <NUM>. In this way, the axial movement of the bushing upwards through the collar of the sleeve may be inhibited.

The bushing <NUM> has an annular shape and includes an opening <NUM> sized to mate with the second reduced diameter section <NUM> of the stud <NUM>, as previously discussed. More specifically, the bushing <NUM> may be press fit, braised, pinned, bonded, threaded, and/or welded to the stud <NUM>. Thus, the bushing <NUM> may be permanently or removably attached to the stud <NUM>. The bushing acts to lock the components of the system together to form a cohesive unit, especially while the system is in a disengaged configuration. The bushing <NUM> may also include a peripheral surface <NUM> that is contoured to interact with the cantilever legs <NUM> and push them in an outward direction when slid through the collet body. In one example, the peripheral surface <NUM> may be tapered in a downward direction. In other examples, the bushing <NUM> may not interact with the cantilever legs <NUM> during engagement.

Additionally, the components of the fastener system may be constructed out of a similar material such as metal (e.g., steel, aluminum, etc.,), a polymer, etc., in one example. However, in other examples, the stud <NUM>, sleeve <NUM>, collet body <NUM>, and/or bushing <NUM> may be constructed out of different materials. For instance, the sleeve may be constructed out of aluminum while the collet body <NUM> may be constructed out of a more spring-biased material, such as steel. Moreover, the materials used to construct the different components in the fastener system may be chosen based on end use requirements. It will be appreciated that for structural applications (e.g., large load bearing structures) the fastener system may be constructed out of steel. On the other hand, when designed for commercial applications the fastener system may employ plastics. Further, in other examples, the fastener system may have a hybrid material construction where both plastic and metal are utilized. Furthermore, when plastic collet bodies, a possibility in the commercial sector, the legs may be in an open position in an engaged and disengaged configuration and flex closed when the collet body is inserted into the sleeve, or when the system is inserted/removed from a bore. In this instance, the plastic may be designed to be easily flexed (e.g., pushed or pulled) by a person to cause the cantilever legs to flex inward and thus allow easy egress of the fastener through the bore.

<FIG> also shows an automated tooling apparatus <NUM> that may be used to manipulate the fastener system and carry out the methods described herein. The tooling apparatus <NUM> may include a processor <NUM> and memory <NUM> (e.g., non-transitory memory) storing instructions executable by the processor. It will be appreciated that the automated tooling apparatus <NUM> may further include tooling attachments, arms, carriages, etc., for manipulating the fastener system.

<FIG> shows a view of the collet body <NUM> partially mated with the sleeve <NUM>. The partial mating of the collet body <NUM> with the sleeve <NUM> is induced by bending the cantilever legs <NUM> inwardly toward the central axis <NUM> and sliding the collet body <NUM> into the sleeve in an upward direction. In the illustrated example, the feet <NUM> are bent inwardly toward the central axis <NUM> such that side surfaces <NUM> of successive extensions are adjacent to one another but still maintain a slight gap there between. However, in other examples, the cantilever legs <NUM> may be bent such that the side surfaces <NUM> may be in contact or near contact during the mating procedure. Additionally, peripheral surfaces <NUM> of the cantilever legs <NUM> are in contact with an inner surface <NUM> of the sleeve <NUM>. Furthermore, the inner surface <NUM> of the sleeve <NUM> may have a greater diameter than the interior threaded section <NUM> of the sleeve <NUM>, shown in <FIG>. Moreover, the inner surface <NUM> of the sleeve <NUM> may also have a diameter <NUM> that is larger than the outer diameter <NUM> of the crown <NUM> of collet body <NUM>, shown in <FIG>. <FIG> shows an expanded view <NUM> of a portion of the sleeve <NUM> and the collet body <NUM> to assist in viewing of specific features of the system. In some of the figures described below additional expanded views are show to achieve the same purpose. Redundant descriptions of these views are omitted.

<FIG> shows the fastener system <NUM> of <FIG> assembled in a disengaged configuration. In the disengaged configuration the feet <NUM> only partially extend through the openings <NUM> of the sleeve <NUM>. <FIG> also shows the stud <NUM> partially threaded into the sleeve <NUM>.

<FIG> shows the head <NUM> of the stud <NUM> having a lower surface <NUM>. It will be appreciated that the lower surface <NUM> may act as a clamping surface in the fastener system <NUM>. The lower surface <NUM> includes a portion that tapers in a downward direction and a portion that extends inwardly. However, other lower surface contours have been contemplated, such as a flat surface.

Aside from the openings <NUM>, the sleeve <NUM> includes a continuous external surface <NUM> that circumferentially surrounds the portions of the collet body besides the feet <NUM>. Using a sleeve <NUM> contoured in this manner enables the collet body to be protected from external forces, such as shear forces. As such, the sleeve <NUM> acts to decouple the cantilever legs of the collet body from shear stresses when used for clamping two structures. In particular, the shear forces are for the most part decoupled from a weaker section (e.g., cantilever legs) and placed onto a stronger section (e.g., the sleeve). As a result, the fastener system has excess capacity, enabling the system to carry additional shear forces. As described herein sheer stress is the component of stress coplanar with a material cross-section. Consequently, the stud <NUM> may be more easily unthreaded from the sleeve <NUM>. However, in other examples the sleeve <NUM> may include additional voids that may reduce the weight of the sleeve. <FIG> also shows the viewing plane <NUM> indicating the cross-sectional view illustrated in <FIG>.

<FIG> shows a cross-sectional view of the fastener system <NUM>, shown in <FIG>. The threaded section <NUM> of the stud <NUM> is shown engaged with the interior threaded section <NUM> of the sleeve <NUM>. The second end <NUM> of the stud <NUM> having the bushing <NUM> attached thereto, is also shown positioned within the crown <NUM> of the collet body <NUM>.

Additionally, <FIG> illustrates the fastener system <NUM> in the disengaged configuration where the cantilever legs <NUM> are not radially loaded by the stud <NUM>. In the disengaged configuration outer surfaces <NUM> of the cantilever legs <NUM> are at least partially spaced away from an inner surface <NUM> of the sleeve <NUM>. Furthermore, in the disengaged configuration the feet <NUM> only partially extend through the openings <NUM> such that they do not radially extend beyond an outer surface <NUM> of the sleeve <NUM>. In this way, the fastener system <NUM> may be easily inserted through bores in structures slated for clamping by the system. However, in other examples, in the disengaged configuration the feet <NUM> may slightly protrude from the openings such that movement of the system through bores would urge the feet back into the openings.

Furthermore, when the feet <NUM> partially extend through the openings <NUM>, the openings function to limit the movement of feet <NUM> and therefore collet body <NUM>. Thus, the relative positions of the sleeve <NUM> and the collet body <NUM> can be essentially fixed to one another when the feet <NUM> are partially mated as well as fully mated with the openings <NUM>.

The first reduced diameter section <NUM> (e.g., unthreaded section) of the stud <NUM> is also designed to allow the stud to freely rotate. This may be particularly useful when unthreading the stud during removal when people or automated tooling machines fail to vary the applied torque while backing out the stud <NUM>. As such, the free spin feature prevents the tool from over torqueing the stud during removal and damaging the system. To enable the free rotation of an axial length <NUM> of the first reduced diameter section <NUM> on the stud is equal to or greater than an axial length <NUM> of the interior threaded section <NUM> of the sleeve <NUM>. The free spin feature may be included in any of the examples or combinations of the examples of the fastener system, described herein. However, in other instances, as described in greater detail herein, the fastener system may be designed with a hard stop feature that does not allow the free rotation of the stud.

<FIG> show an example of the fastener system <NUM> with a retainer <NUM>. Specifically, <FIG> shows an exploded view of the fastener system <NUM>, <FIG> shows an assembled view of the fastener system depicted in <FIG> shows a cross-sectional view of the fastener system, illustrated in <FIG>. Viewing plane <NUM> shown in <FIG> indicates the cross-section of <FIG>. The fastener system <NUM> is again shown to include the stud <NUM>, sleeve <NUM>, collet body <NUM>, and bushing <NUM>. The retainer <NUM> includes prongs <NUM> configured to extend through gaps <NUM> between the cantilever legs <NUM> in the collet body <NUM>. Consequently, the collet body <NUM> may be even more securely retained within the sleeve <NUM>.

<FIG> show a sequence for clamping an upper and lower structure, <NUM> and <NUM>, using the fastener system <NUM>. In particular, <FIG> shows the fastener system <NUM> prior to insertion through bores, <NUM> and <NUM>, in the upper structure <NUM> and the lower structure <NUM>, respectively, slated for clamping by the system. In one example, the upper structure <NUM> may be a floor panel in an aircraft and the lower structure <NUM> may be a floor beam. However, the fastener system <NUM> may be used to clamp numerous structures in other aerospace components as well as structures in other fields such as construction, the maritime industry, the automotive industry, etc..

In <FIG> the fastener system <NUM> is in the disengaged configuration to enable easy insertion through the bores <NUM> and <NUM>. When the fastener system <NUM> is in the disengaged configuration the feet <NUM> are partially mated with the openings <NUM>. In such a configuration, the openings <NUM> substantially inhibit movement of the collet body <NUM> with regard to the sleeve <NUM>. As shown, the upper bore <NUM> has a greater diameter <NUM> than a diameter <NUM> of the lower bore <NUM>. Moreover, the upper bore <NUM> may be sized to mate with the facetted collar <NUM> in the sleeve <NUM>. For instance, the upper bore and facetted collar may have a corresponding female and male hexagonal shape. In this way, the upper bore <NUM> allows axial movement of the sleeve through the bore and restricts (e.g., substantially inhibits) rotation of the sleeve <NUM> with regard to the bore. However, in other examples, a portion of the sleeve may be positioned external to the bore <NUM> and a tool may be used to restrict rotational movement of the sleeve.

<FIG> shows the upper structure <NUM> and the lower structure <NUM> brought into contact with one another and the fastener system <NUM> inserted through the bores, <NUM> and <NUM>, in the upper and lower structures, <NUM> and <NUM>, shown in <FIG> also shows a portion of the stud <NUM> positioned above the upper structure <NUM>.

<FIG> illustrated a side view of the fastener system <NUM> and the upper and lower structures, <NUM> and <NUM>, shown in <FIG>. As illustrated, a portion of the sleeve <NUM> including the openings <NUM> extends below the lower structure <NUM>. Conversely, the head <NUM> of the stud <NUM> extends above the upper structure <NUM>. <FIG> also shows a viewing plane <NUM> indicating the cross-sectional view illustrated in <FIG>.

<FIG> shows the fastener system <NUM> in the disengaged configuration. <FIG> also shows the facetted collar <NUM> in the sleeve <NUM> in contact with an upper surface <NUM> of the lower structure <NUM>. In this way, the sleeve <NUM> can be inhibited from sliding through the bore <NUM> in the lower structure <NUM>. Additionally, in the disengaged configuration, shown in <FIG>, the stud <NUM> is allowed to spin freely due to the first reduced diameter section <NUM> of the stud <NUM> being aligned with the interior threaded section <NUM> of the sleeve <NUM>.

<FIG> depicts the fastener system <NUM> in an engaged configuration where the stud <NUM> is advanced into the sleeve <NUM> via rotation of the stud <NUM>. Advancing the stud <NUM> into the sleeve <NUM> and collet body <NUM> pushes the feet <NUM> outwardly in radial directions such that they protrude out of the openings <NUM>. As such, the upper surfaces <NUM> of the feet <NUM> may act as a lower clamping surface. <FIG> also shows the lower surface <NUM> of the head <NUM> of the stud <NUM> in contact or near contact with an upper surface <NUM> of the upper structure <NUM>. Thus, the lower surface <NUM> of the head <NUM> may therefore act as an upper clamping surface. Furthermore, when the fastener system <NUM> is in the engaged configuration the lower sides <NUM> of the openings <NUM> are in contact or near contact with the lower surfaces <NUM> of the feet <NUM>. When such contact occurs forces are transferred from the sleeve to the feet.

<FIG> shows the fastener system <NUM> in the engaged configuration where the stud <NUM> is further advanced into the sleeve <NUM>. Advancing the stud <NUM> into the sleeve <NUM> further decreases the distance between the feet <NUM> and the head <NUM> of the stud <NUM> to generate a clamping force to hold the upper structure <NUM> to the lower structure <NUM>. In particular, the upper surfaces <NUM> of the feet <NUM> are in contact with the lower structure <NUM> and the lower surface <NUM> of the head <NUM> of the stud <NUM> is in contact with the upper structure <NUM> to provide engagement between the structures. It will be appreciated that the directions of the clamping forces may in some cases be parallel to the central axis of the fastener system. Furthermore, when fastener system is engaged (e.g., fully engaged) the feet <NUM> of the cantilever legs <NUM> see shear stress created by the tension in the fastening system (i.e., upward force of the sleeve and the downward reaction or static reaction generated by the structure being fastened). Specifically, the axial load in the fastener system is transferred from the sleeve <NUM> to the feet <NUM> of the collet body <NUM> and then to the lower structure <NUM>. To enable the force transfer between the feet <NUM> and the sleeve <NUM>, lower surfaces <NUM> of the feet are in contact with lower sides <NUM> of the openings <NUM>. Additionally, it will be appreciated that in the engaged configuration the upper surfaces <NUM> of the feet <NUM> may be spaced away from the upper sides <NUM> of the openings <NUM>. Furthermore, in the engaged configuration the cantilever legs <NUM> and feet <NUM> of the collet body may be prohibited or blocked from moving toward the central axis <NUM>, in one example, due to the position of the stud <NUM>. In particular, in the engaged configuration the stud <NUM> that has opened the legs may be positioned and contoured to prevent the cantilever legs <NUM> from retracting into the openings <NUM>. Furthermore, the lower surfaces <NUM> of the feet <NUM> may be correspondingly contoured with the lower sides <NUM> of the openings <NUM>. For instance, the lower surfaces <NUM> of the feet <NUM> and the lower sides <NUM> of the openings <NUM> may be planar. In such an example, the contact forces will hold these two flat surfaces together (in contact) and prevent rotation towards the central axis <NUM>. However, in other examples, the stud <NUM> may be configured to block the cantilever legs <NUM> from closing and the feet <NUM> may not be in direct contact with the lower surfaces <NUM> of the openings <NUM>.

Additionally, outer surfaces <NUM> of the cantilever legs <NUM> may be adjacent to (e.g., near contact or direct contact) an inner surface <NUM> of the sleeve <NUM> when the fastener system <NUM> is in the engaged configuration, in one example. It will be appreciated that the outer surfaces <NUM> of the cantilever legs <NUM> and the inner surface <NUM> of the sleeve <NUM> may have a small amount of clearance there between, due to design choice and/or manufacturing tolerances.

<FIG> depicts the fastener system <NUM> with the stud <NUM> even further advanced into the sleeve. Advancing the stud into the sleeve <NUM> allows an additional clamping force to be exerted on the upper structure <NUM> and the lower structure <NUM> such that the lower structure is compressed. In this way, the fastener system can be used to securely clamp two structures to one another.

<FIG> shows another example of a fastener system <NUM>. The fastener system <NUM>, shown in <FIG>, includes some components that are similar to those employed in the fastener system <NUM>, shown in <FIG>. For example, the fastener system <NUM>, shown in <FIG>, includes a stud <NUM>, sleeve <NUM>, collet body <NUM>, and bushing <NUM>. The aforementioned components may have at least some similar contours and/or functions to those included in the fastener system <NUM>, shown in <FIG>. Therefore, redundant description is omitted. However, in the fastener system <NUM>, shown in <FIG>, the collet body <NUM> includes an interior threaded section <NUM> that is configured to engage a threaded section <NUM> in the stud <NUM>. On the other hand, the sleeve <NUM> includes an unthreaded interior section <NUM>.

<FIG> shows a side view of the fastener system <NUM> shown in <FIG> in an assembled state. Feet <NUM> in the collet body are partially mated with the openings <NUM> in the sleeve <NUM> such that the feet do not protrude beyond the side of the sleeve. Viewing plane <NUM> indicates the cross-sectional view shown in <FIG>.

<FIG> shows a cross-sectional view of the fastener system <NUM> shown in <FIG>. The interior threaded section <NUM> of the collet body <NUM> is not engaged with the threaded section <NUM> of the stud <NUM>, in the configuration shown in <FIG>. However, it will be appreciated the said threading may occur when the stud is advanced into the collet body. It will also be appreciated that advancing the threading between the collet body <NUM> and the stud <NUM> will generate a clamping action similar to the clamping action described above with regard to <FIG>. Thus, the fastener system <NUM> may also achieve decoupling of the shear stresses from the collet body. However, in the fastener system <NUM>, shown in <FIG>, the cantilever legs <NUM> of the collet body <NUM> see two stress creating activities. The first stress being bending the legs open from a neutral position, similar to the first example of the fastener system, shown in <FIG>. The second stress, corresponding to the addition of the interior threaded section <NUM> in the collet body <NUM>, being clamping forces that are carried directly through the cantilever legs <NUM> that already see stress from being bent open. These two stress creating activities are additive and thus may load the collet more than other configurations.

<FIG> shows another example fastener system <NUM> (e.g., removable fastener system) that includes an auxiliary structure <NUM> at least partially enclosing a sleeve <NUM>. Feet <NUM> are shown partially mated with openings <NUM> in the sleeve <NUM>. The auxiliary structure <NUM> further includes a facetted collar <NUM> and detent <NUM> configured to be gripped or held by a tool (e.g., automated tool). However, in other examples, the collar may not include a detent. Viewing plane <NUM> defines the cross-sectional view depicted in <FIG>.

<FIG> and <FIG> show a cross-sectional view of the fastener system <NUM> shown in <FIG> in two stages of disengagement. <FIG> shows a collet body <NUM> enclosed within the sleeve <NUM>. It will be appreciated that the sleeve <NUM> and collet body <NUM> may have similar characteristics or combinations of characteristics to those that are described herein with regard to the other fastener system examples. Thus, the sleeve <NUM> and the collet body <NUM> may interact (e.g., thread and unthread) with a stud <NUM> to engage and disengage the feet <NUM>.

The auxiliary structure <NUM> includes a lower lip <NUM> extending inwardly toward a central axis <NUM>. The lower lip <NUM> may have the shape of a lobe, hexagonal shelf, or other shape that inhibits axial movement of the collar of the sleeve <NUM> beyond the lower end of the auxiliary structure. Specifically, an upper surface <NUM> of the lower lip <NUM> is shown in contact with a surface <NUM> of a collar <NUM> of the sleeve <NUM>. In this way, the fastener system <NUM> may be self-contained, facilitating efficient tooling of the system. However, in other examples, the auxiliary structure <NUM> may not include a lower lip <NUM>.

<FIG> additionally depicts the stud <NUM> partially enclosed by the auxiliary structure <NUM>. The auxiliary structure <NUM> includes an upper stop <NUM> and a lower stop <NUM> limiting the axial movement of the stud <NUM>. In particular, a head <NUM> of the stud <NUM> includes a protrusion <NUM> that is delimited by the upper and lower stops, <NUM> and <NUM>. In this way, the head <NUM> of the stud <NUM> may be kept within the auxiliary structure <NUM> to reduce the profile of the fastener system <NUM> and protect the head of the stud. It will also be appreciated that the interior portion <NUM> in the auxiliary structure where the head <NUM> of the stud <NUM> resides enables rotation of the head <NUM>. For instance, the interior portion <NUM> may be cylindrical in shape and have a larger diameter than the head <NUM>.

In <FIG> a gap <NUM> is shown between the lower stop <NUM> and the head <NUM>. The gap <NUM> accommodates axial movement of the head when the stud <NUM> is fully disengaged from the sleeve <NUM> and collet body <NUM>. Movement of the head upwards allows the unthreaded section <NUM> of the stud <NUM> to align with the interior threaded section <NUM> of the sleeve <NUM>, enabling free rotation of the stud with regard to the sleeve.

An interior portion <NUM> of the auxiliary structure <NUM> may be configured to allow axial movement the sleeve there through but limit (e.g., inhibit) rotation of the sleeve <NUM>. Such functionality may be achieved by contouring the interior portion such that a facetted collar <NUM> of the sleeve <NUM> mates therein. For instance, the interior portion and the facetted collar may have associated hexagonal shapes.

<FIG> shows the fastener system <NUM> with the head <NUM> of the stud <NUM> driven downward into contact with the lower stop <NUM>. Specifically, the protrusion <NUM> in the head <NUM> may be in contact or near contact with the lower stop <NUM>. Driving the stud downward also induces engagement between a threaded section <NUM> of the stud <NUM> and the interior threaded section <NUM> of the sleeve <NUM>. <FIG> also shows the auxiliary structure <NUM> with the lower lip <NUM> functioning to retain the sleeve <NUM>, as previously mentioned.

<FIG> shows the fastener system <NUM>, illustrated in <FIG> prior to clamping an upper structure <NUM> to a lower structure <NUM>. Again both the upper and lower structures include bores <NUM> and <NUM>, respectively. <FIG> depicts a lower surface <NUM> of the auxiliary structure <NUM> in contact with the upper structure <NUM>. The lower auxiliary structure surface <NUM>, therefore, acts as an upper clamping surface. As in the case of the previous fastener examples, upper surfaces <NUM> of feet <NUM> function as a lower clamping surface.

<FIG> also shows the stud <NUM> with a lower unthreaded section <NUM> that may have a greater diameter than an upper threaded section <NUM>. However, the lower unthreaded section <NUM>, in other examples, may have a diameter that is smaller than or equal to the diameter of the upper threaded section <NUM>. Furthermore, the lower unthreaded section <NUM> has a diameter <NUM> that is greater than an inner diameter <NUM> of a threaded section <NUM> of the sleeve <NUM>. In this way, the fastener system <NUM> may be locked together and act as a self-contained system. As a result, the system may be easily grasped and pulled out of a bore. The lower unthreaded section <NUM> smoothly urges the cantilever legs <NUM> outward with reduced abrasion when the slid there through. The lower unthreaded section <NUM> is attached (e.g., press fit, braised, bonded, threaded, etc.,) to the stud <NUM> as a separate component, in the illustrated example. The lower unthreaded section <NUM> therefore acts as an elongated bushing and performs a similar function. However, in other instances, the lower unthreaded section <NUM> may include of a region without threads on the stud <NUM>, a bushing, an elongated bushing, or any combination of bushings and regions without threads. Furthermore, as previously discussed, in other examples, the collet body <NUM> may alternatively include the threaded section that engages with the stud.

<FIG> illustrates another example of a fastener system <NUM>. The fastener system <NUM>, shown in <FIG>, again includes a stud <NUM>, an auxiliary structure <NUM>, a sleeve <NUM>, and a collet body <NUM>. It will be appreciated that the stud <NUM>, sleeve <NUM>, and collet body <NUM> may have any of the features or combinations of the features of the studs, sleeves, and collet bodies in any of the fastener systems described herein.

However, in <FIG> the auxiliary structure <NUM> includes an upper stop <NUM> and a lower stop <NUM> that substantially inhibit axial movement of the head <NUM> of the stud <NUM>. Thus, the upper stop <NUM> is nearly in contact with an upper surface <NUM> of the head <NUM> while the lower stop <NUM> is in contact with a lower surface <NUM> of the head <NUM>. Thus, a small gap may exist between the upper stop <NUM> and the head <NUM> that may be necessitated by manufacturing constraints, in some examples. This type of fastener system may be desirable in applications with packaging constraints. For example, it may be desirable in some applications to diminish the vertical profile of the system. Furthermore, the configuration of the fastener system, shown in <FIG>, does not free spin in reverse. Free spin is an optional feature of the fastener system that enables the stud <NUM> to freely rotate with regard to the sleeve <NUM> and the collet body <NUM> when the stud is completely unthreaded from the sleeve, as previously discussed. A fastener system configuration that does not free spin in reverse may be desired by some robotic manufacturers, due to the fact that some robots, in reverse, will sense the spike in torque, referred to as a hard-stop, when the fastener bottoms out (e.g., goes solid and acts as if everything is fixedly coupled together) in reverse.

It will be appreciated that in some instances the hard stop feature of the fastener may be included in any of the examples of the fastener system or combinations of the fastener systems, described herein. The bottoming out of the fastener is shown in the detail view of the threads engagement in <FIG> also shows the auxiliary structure <NUM> including a lower lip <NUM> functioning to retain the sleeve <NUM>, as previously mentioned.

<FIG> shows another example of a fastener system <NUM> and <FIG> shows a cross-section of the fastener system. Viewing plane <NUM> denotes the cross-sectional view shown in <FIG>. As depicted in <FIG>, the fastener system <NUM> includes an auxiliary structure <NUM> with a stop <NUM> preventing a head <NUM> of a stud <NUM> from traveling into an interior portion <NUM> of the auxiliary structure <NUM>. It will be appreciated that an interior surface <NUM> of the stop <NUM> is unthreaded, in the depicted example. Therefore, the auxiliary structure may slide up and down freely with regard to the stud <NUM> and a sleeve <NUM>. However in other instances, the stop <NUM> may have an interior threaded section. <FIG> also shows the auxiliary structure <NUM> including a lower lip <NUM> functioning to retain the sleeve <NUM>, as previously mentioned. <FIG> additionally shows the fastener system <NUM> including a collet body <NUM> that may have at least some of the features, functions, etc., of the other collet bodies described herein. <FIG> also shows a bushing <NUM>. The bushing <NUM> and the lower lip <NUM> may function similarly to the previously described bushings and lower lips. <FIG> shows the fastener system <NUM> in a disengaged configuration where the stud <NUM> is not threaded into the sleeve <NUM>. However, in the fastener system <NUM> when the stud <NUM> is threaded into the sleeve, in an engaged configuration, the head <NUM> of the stud <NUM> moves closer to (e.g., axially translate in a downward direction) the stop <NUM>. Specifically, in some examples, when the stud <NUM> is fully threaded into the sleeve <NUM> the head <NUM> of the stud may come into contact with the stop <NUM>. Moreover, during the initial phase said threading (e.g., prior to the head <NUM> contacting the stop <NUM>) the relative position of the auxiliary structure <NUM> and the sleeve <NUM> may remain unchanged, in some examples. However, during a later phase in said threading (e.g., subsequent to the head <NUM> contacting the stop <NUM>) the sleeve <NUM> may axial translate upwards into the auxiliary structure <NUM>. It will be appreciated that this feature may be included in any of the examples of the fastener system or combinations of the fastener systems, described herein.

<FIG> shows an example of a sleeve <NUM> and collet body <NUM> that may be included in any of the fastener systems described herein. As shown, the sleeve <NUM> includes two openings <NUM> and the collet body <NUM> includes two cantilever legs <NUM> while the previous embodiments of the fastener system include three sleeve opening and corresponding cantilever legs. However, fasteners with a lower or greater number of openings and cantilever legs have been envisioned.

<FIG> shows another example fastener system <NUM> where a stud <NUM> includes an upper threaded section <NUM>, an unthreaded section <NUM>, and a lower threaded section <NUM>. In the engaged configuration shown in <FIG>, the lower threaded section <NUM> urges cantilever legs <NUM> outward through openings <NUM> in a sleeve <NUM>. Specifically in the example illustrated in <FIG>, the lower threaded section <NUM> extends to an end <NUM> of the stud <NUM>. However, in other instances, the lower threaded section <NUM> may not fully extend down the stud <NUM>.

<FIG> show another embodiment of a fastener system <NUM>. It will be appreciated that the fastener system <NUM> may include at least a portion of the structural and/or functional features of any of the fastener systems described herein. Moreover, combining features from three or more fastener systems have also been envisioned.

<FIG> shows an exploded view of the fastener system <NUM>. The fastener system <NUM> again includes a stud <NUM>, a collet body <NUM>, and a sleeve <NUM>. The sleeve <NUM> includes openings <NUM> designed to mate with feet <NUM> of cantilever legs <NUM> in the collet body <NUM> when the fastener system <NUM> is assembled and clamping upper and lower structures (e.g., work pieces).

Additionally, the fastener system <NUM> includes a locking ring <NUM>. The locking ring <NUM> is designed to retain the stud <NUM> and collet body <NUM> within the sleeve <NUM>. The locking ring <NUM> includes a slit <NUM> allowing for expansion/contraction of the locking ring during fastener assembly. In this way, fastener assembly may be simplified and efficiently carried out. In the depicted example, the locking ring <NUM> has an inner diameter <NUM> that is greater than a diameter <NUM> of a reduced diameter section <NUM> of the stud <NUM> and less than a diameter <NUM> of a lower threaded section <NUM> of the stud <NUM>. In this way, the reduced diameter section <NUM> of the stud <NUM> may travel axially with the sleeve <NUM> while preventing the lower threaded section <NUM> of the stud <NUM> as well as a head <NUM> of the stud from axially egress from the sleeve <NUM>. As such, the components in the fastener system can be kept together during installation and removal of the fastener. Therefore, the likelihood misplaced components during fastener installation and removal is reduced (e.g., prevented).

The lower threaded section <NUM> of the stud <NUM> may, in one example, be a fully formed thread that forms an angle at a crest. However, in other examples, the lower threaded section <NUM> may be a truncated thread. The truncation adds strength to the crest of the threads. Such strength may be beneficial and toughen the threads when they are pushing against the cantilever legs <NUM> of the collet body <NUM>. Furthermore, by providing a stud with an expanded diameter section at the end of the stud <NUM> away from the head as opposed to a bushing, the strength of the stud may be increased and the assembly of the fastener system may be simplified, thereby reducing manufacturing costs.

In the illustrated example, the reduced diameter section <NUM> of the stud <NUM> includes an unthreaded section <NUM> and a threaded section <NUM>. In the illustrated example, the diameters of the threaded section <NUM> and the unthreaded section <NUM> of the reduced diameter section <NUM> of the stud <NUM> are equivalent. However, in other examples, the diameter along the reduced diameter section of the stud may vary along its length. In other examples, the reduced diameter section may not be threaded.

In the example, shown in <FIG>, the sleeve <NUM> includes a lower threaded section <NUM> and an upper threaded section <NUM> designed to threadingly engage with the lower threaded section <NUM> of the stud <NUM>. The lower threaded section <NUM> and the upper threaded section <NUM> are positioned in an aperture <NUM> of the sleeve <NUM>. Both of the threaded sections may be designed to threadingly engage with the lower threaded section <NUM> of the stud <NUM>. It will be appreciated the sleeve <NUM> may include either the upper threaded section or the lower threaded section, in other examples. On the other hand, the collet body <NUM> does not include a threaded section and in contrast includes an unthreaded interior surface <NUM>. However, as previously discussed, in some configurations, the collet body <NUM> may include a threaded section threadingly engaging with the stud <NUM>.

The sleeve <NUM> also includes a lower reduced diameter section <NUM> having an unthreaded outer surface <NUM>. The lower reduced diameter section <NUM> may protect the stud <NUM> during installation/removal of the fastener system <NUM>, for example.

<FIG> shows an assembled view of the fastener system <NUM>. Again, the stud <NUM>, collet body <NUM>, and sleeve <NUM> are illustrated. It will be appreciated that the fastener system <NUM> shown in <FIG> is in a disengaged configuration. A viewing plane <NUM> defining the cross-sectional view shown in <FIG> is depicted in <FIG>.

<FIG> shows a cross-sectional view of the fastener system <NUM>. The stud <NUM>, collet body <NUM>, and sleeve <NUM> are again shown. The sleeve <NUM> includes a body <NUM> having the openings <NUM>, in the illustrated example. The locking ring <NUM> is also shown in <FIG>. As illustrated, the locking ring <NUM> is positioned in a recess <NUM> of the sleeve <NUM>. As shown, the locking ring <NUM> at least partially circumferentially surrounds the reduced diameter section <NUM> of the stud <NUM> and limits axial movement of the threaded section <NUM> of the stud <NUM> beyond the central aperture of the sleeve <NUM>.

Cantilever legs <NUM> of the collet body <NUM> are also shown in <FIG>. The cantilever legs <NUM> are in a neutral position in <FIG>. Specifically, the cantilever legs <NUM> extend inward in the neutral position. As such, the cantilever legs <NUM> may flex outwardly when mated with openings <NUM> in the sleeve <NUM>. However, other neutral leg positions have been envisioned. The enlarged area in <FIG> is indicated at <NUM>.

<FIG> shows an enlarged view of a portion of the fastener system <NUM>. The threaded section <NUM> of the stud <NUM> is shown in contact with the cantilever legs <NUM> of the collet body <NUM>. Additionally, the cantilever legs <NUM> are shown positioned in openings <NUM> in the sleeve <NUM>. As show, a gap <NUM> exist between a portion of an outer surface <NUM> of the cantilever legs <NUM> and an interior surface <NUM> of the sleeve <NUM>.

The locking ring <NUM> in the fastener system <NUM> is also shown in <FIG>. The locking ring <NUM> is shown contacting the threaded section <NUM> of the stud <NUM>. In this way, the locking ring <NUM> may limit the axial movement of the stud <NUM>, thereby retaining components in the system. However, it will be appreciated that the locking ring <NUM> allows the reduced diameter section <NUM> to axial translate with regard to the ring, allowing for the intended clamping action in the system.

The threaded section <NUM> of the stud <NUM> is also shown contacting interior surfaces <NUM> of the cantilever legs <NUM>. It will be understood that downward movement of the threaded section <NUM> of the stud <NUM> further expands the cantilever legs <NUM>. The threads <NUM> in the threaded section <NUM> may be fully formed, in one example. However, in other examples, the threads <NUM> in the threaded section <NUM> may be truncated.

The lower threaded section <NUM> of the sleeve <NUM> is also shown in <FIG>. As previously discussed, the lower threaded section <NUM> of the sleeve <NUM> mates with the lower threaded section <NUM> of the stud <NUM>.

<FIG> shows a cross-sectional view of the fastener system <NUM> in an engaged configuration where the feet <NUM> of the cantilever legs <NUM> extend through the openings <NUM> in the sleeve <NUM>. It will be appreciated that threading the lower threaded section <NUM> of the stud <NUM> into the lower threaded section <NUM> of the sleeve <NUM> places the fastener system <NUM> in the engaged configuration. The enlarged area in <FIG> is indicated at <NUM>.

<FIG> shows a detailed view of a portion of the fastener system <NUM>. As shown, a gap <NUM> exist between the outer surface <NUM> of the cantilever legs <NUM> and the interior surface <NUM> of the sleeve <NUM>. This clearance zone allows the cantilever legs <NUM> to expand to a greater diameter when interacting with the lower threaded section <NUM> of the stud <NUM>. In this way, mechanical binding and leg deformation caused by over-extension of the cantilever legs <NUM> may be avoided. Furthermore, designing the cantilever legs <NUM> in this manner allows the legs to be repeatedly expanded and contracted as the stud <NUM> is threaded/unthreaded into/from the sleeve <NUM> without permanent deformation.

Furthermore, the feet <NUM> are in contact with the lower threaded section <NUM> (e.g., reduced diameter section) of the stud <NUM>, in the illustrated example. Such an arrangement may provide a desired load distribution in the fastener system. For instance, a large amount (e.g., the majority) of the loads experienced by the fastener may be transferred to the sleeve, in such a configuration. As such, transfer of the loads to selected sections in the fastener allows the fastener to be designed with increased load carrying capabilities and reduces the likelihood mechanical binding, leg degradation (e.g., permanent deformation, failure, etc.), etc..

<FIG> show an engagement sequence (e.g., clamping up sequence) in a fastener system <NUM>. <FIG> show the fastener system <NUM> including the stud <NUM>, collet body <NUM> with cantilever legs <NUM> having feet <NUM> and a sleeve <NUM> with openings <NUM>. Specifically, <FIG> specifically show the fastener system <NUM> in various stages of increasing clamping engagement. It will be appreciated that threading the stud further into the sleeve provides increasing fastener clamping engagement.

As shown in <FIG>, the stud <NUM> begins pushing the feet <NUM> of the cantilever legs <NUM> through the openings <NUM>. As the stud <NUM> is advanced with regard to the sleeve <NUM>, induced via stud rotation, the cantilever legs <NUM> are moved further outward to facilitate structure (e.g., work piece) clamping. Additionally, a gap <NUM> exists between an inner surface <NUM> of the sleeve <NUM> and surfaces <NUM> of the cantilever legs <NUM>. As the fastener system <NUM> is transitioned into an engaged configuration the size of the gap <NUM> changes due to the flexion characteristics of the cantilever legs <NUM>.

<FIG> shows the feet <NUM> of the cantilever legs <NUM> extending further through the openings <NUM>. An increased diameter section <NUM> of the stud <NUM> pushes the feet <NUM> of the cantilever legs <NUM> further outward. In the configuration shown in <FIG> the legs are over-expanded as the legs interact with the increased diameter section of the stud. In other words, the legs radially expand beyond a clamping position. <FIG> also depicts a smaller gap between the cantilever legs <NUM> and the inner surface <NUM> of the sleeve <NUM> when compared to the configuration of the fastener system in <FIG>. It will be appreciated that the smaller gap is caused by increased outward flexion in the cantilever legs <NUM>.

The increased diameter section <NUM> of the stud <NUM> has a larger diameter than a reduced diameter section <NUM> of the stud <NUM>. In one example, the reduced diameter section <NUM> of the stud <NUM> may be unthreaded. However, in other examples, the reduced diameter section <NUM> of the stud <NUM> may include a threaded section and an unthreaded section, as previously discussed. Furthermore, the increased diameter section <NUM> of the stud <NUM> may be threaded.

<FIG> shows the feet <NUM> of the cantilever legs <NUM> extending through the openings <NUM> in the sleeve <NUM>. As such, a portion of the outer surfaces <NUM> of the cantilever legs <NUM> are in face sharing contact with the inner surface <NUM> of a lower structure <NUM>.

<FIG> shows the fastener system <NUM> in an engaged configuration that clamps a lower structure <NUM>. Specifically, an upper surface <NUM> of the feet <NUM> is in contact with an outer surface <NUM> with the lower structure <NUM>. As previously, discussed the fastener system <NUM> may clamp an upper structure (not shown). In the clamping configuration of the fastener system <NUM>, shown in <FIG> a large amount of shear stress is transferred from the cantilever leg feet <NUM> to the sleeve <NUM>. In this way, the shear stress is essentially decoupled from the collet body <NUM>. As such, a more robust fastener is provided which efficiently transfers these stresses to selected components in the system designed to carry the loads. The likelihood of fastener degradation as well as the stresses impeding the intended operation of the fastener is therefore substantially reduced.

<FIG> show another example of a fastener system <NUM>. The fastener system <NUM> again includes a stud <NUM>, a collet body <NUM>, a sleeve <NUM>, and a bushing <NUM>.

<FIG> specifically shows the stud <NUM> including a threaded section <NUM> and a first unthreaded section <NUM> (e.g., decreased diameter unthreaded section) and a second unthreaded section <NUM> (e.g., increased diameter unthreaded section). When assembled the bushing <NUM> may be mated with the second unthreaded section <NUM> of the stud <NUM>. It will be appreciated that the first unthreaded section <NUM> of the stud functions to allow the stud <NUM> to spin freely when backed out of a threaded section <NUM> of the collet body <NUM>. Again, cantilever legs <NUM> in the collet body <NUM> are shown including feet <NUM>. When assembled, the feet <NUM> extend into openings <NUM> in the sleeve <NUM>. The degree to which the fastener system <NUM> is clamped up dictates the degree to which the feet <NUM> extend through the openings <NUM> in the sleeve <NUM>, as previously discussed.

<FIG> shows an assembled view of the fastener system <NUM>, shown in <FIG>. A viewing plane <NUM> defining the cross-sectional view shown in <FIG>, is indicated in <FIG>.

<FIG> shows the first unthreaded section <NUM> of the stud <NUM> in axial alignment with the threaded section <NUM> of the collet body <NUM>. As such, the stud <NUM> may freely spin with regard to the collet body <NUM>. In this way, the chance of damaging the fastener when unclamping the fastener is reduced. For instance, when the stud <NUM> is unthreaded from the sleeve <NUM> the second unthreaded section will align with the threaded section <NUM> of the sleeve <NUM>. Consequently, the stud <NUM> will freely rotate with regard to the sleeve <NUM>. As a result, axial separation between the stud <NUM> and the sleeve <NUM> is essentially limited to prevent the bushing <NUM> from being damaged.

Additionally, the bushing <NUM> and threaded section <NUM> of the stud <NUM> work in conjunction with the second unthreaded section <NUM> of the stud <NUM> and cantilever legs <NUM> to collectively trap and lock the components in the fastener together.

<FIG> shows a detailed view of a section of the fastener system <NUM> shown in <FIG> shows the diameter <NUM> of the threaded section <NUM> of the stud <NUM> exert an axial force on the cantilever legs <NUM> responsive to rotation of the stud via installation personnel operating a manual tool or an automated tooling apparatus.

<FIG> shows the fastener system <NUM> with the stud <NUM> further rotated into the sleeve <NUM>. Responsive to the axial translation of the stud <NUM> with regard to the sleeve <NUM>, the threaded section <NUM> of the stud <NUM> pushes the feet <NUM> of the cantilever legs <NUM> through the openings <NUM> in a body <NUM> of the sleeve <NUM>. The enlarged area in <FIG> is indicated at <NUM>.

<FIG> shows a detailed view of the fastener system <NUM>, shown in <FIG>. As shown, the cantilever legs <NUM> are nominally opened and riding on the stud <NUM>. It will be appreciated that the configuration of the fastener system <NUM> shown in <FIG> may be a desirable load-carrying configuration. In such a configuration the threaded section <NUM> of the stud <NUM> fully engages (e.g., fully engages) with the threaded section <NUM> of the body <NUM> of the sleeve <NUM>.

<FIG> show another example of a fastener system <NUM>. The fastener system <NUM> again includes a stud <NUM>, a collet body <NUM>, and a sleeve <NUM>. The stud <NUM> in the system includes an upper unthreaded section <NUM>, an upper threaded section <NUM>, a lower unthreaded section <NUM>, and a lower threaded section <NUM>.

<FIG> shows the sleeve <NUM> including an upper threaded section <NUM> and a lower threaded section <NUM>. Both the threaded sections <NUM> and <NUM> of the sleeve <NUM> are included in an interior aperture of the stud <NUM>.

The collet body <NUM> includes a slit <NUM>. Surfaces <NUM> of the collet body <NUM> define the boundary of the slit <NUM>. In the depicted example, the surfaces <NUM> extend down sides of cantilever legs <NUM> of the collet body <NUM>. It will be appreciated that the slit <NUM> is circumferentially positioned between two of the cantilever legs <NUM> of the collet body <NUM>, in the illustrated example. However, slit <NUM> may have other profiles, in other examples. For instance, the slit may extend down a leg in the collet body, splitting the leg in two. The slit <NUM> may accommodate radial expansion and retraction of the stud <NUM> during installation and removal of the fastener system <NUM>. Specifically, it will be appreciated that the split collet body <NUM> may help facilitate insertion of the collet body into the sleeve <NUM>. This may be particularly useful when the sleeve <NUM> includes both an upper and lower threaded section that axially protrude into the central aperture in the sleeve <NUM>. It will be appreciated that the lower threaded section <NUM> of the stud <NUM> interacts with cantilever legs <NUM> to radially expand the legs when the fastener is brought into clamping engagement with work pieces.

<FIG> shows an assembled view of the fastener system <NUM>. Viewing plane <NUM> defines the cross-sectional view shown in <FIG>.

<FIG> shows the fastener system <NUM> in an engaged configuration (e.g., clamping configuration). As shown, the lower unthreaded section <NUM> of the stud <NUM> is aligned with the upper threaded section <NUM> of the sleeve <NUM>. As previously discussed, alignment between the unthreaded section <NUM> of the stud <NUM> and the upper threaded section <NUM> of the sleeve <NUM> allows the stud to freely rotate with regard to the sleeve <NUM>. To further engage the stud <NUM> with the sleeve <NUM> the stud must be moved axially downward with regard to the sleeve <NUM> to initiate engagement between the upper threaded section <NUM> of the stud <NUM> and the upper threaded section <NUM> of the sleeve <NUM>. In this way, the stud <NUM> may be initially guided through the sleeve <NUM> during an initial stage of fastener clamping. Additionally, the cantilever legs <NUM> are in a neutral position in the configuration shown in <FIG>. In such a configuration, feet <NUM> of the cantilever legs <NUM> only partially extend through openings <NUM> in the sleeve <NUM>.

<FIG> shows the fastener system <NUM> in an engaged configuration. As shown, the upper threaded section <NUM> of the stud <NUM> is interacting with the cantilever legs <NUM> to expand the legs such that they radially extend through the openings <NUM> in the sleeve <NUM>. In the fastener configuration in <FIG> the feet <NUM> extend through the openings <NUM> due to the outward flexion of the cantilever legs <NUM> caused by the interaction between the upper threaded section <NUM> of the stud <NUM> and the cantilever legs. <FIG> also shows the upper threaded section <NUM> of the stud <NUM> in the fastener system <NUM> engaging with the lower threaded section <NUM> of the sleeve <NUM>.

<FIG> show example configurations with relative positioning of the various components. If shown directly contacting each other, or directly coupled, then such elements may be referred to as directly contacting or directly coupled, respectively, at least in one example. Similarly, elements shown contiguous or adjacent to one another may be contiguous or adjacent to each other, respectively, at least in one example. As an example, components laying in face-sharing contact with each other may be referred to as in face-sharing contact. As another example, elements positioned apart from each other with only a space there-between and no other components may be referred to as such, in at least one example. As yet another example, elements shown above/below one another, at opposite sides to one another, or to the left/right of one another may be referred to as such, relative to one another. Further, as shown in the figures, a topmost element or point of element may be referred to as a "top" of the component and a bottommost element or point of the element may be referred to as a "bottom" of the component, in at least one example. As used herein, top/bottom, upper/lower, above/below, may be relative to a vertical axis of the figures and used to describe positioning of elements of the figures relative to one another. As such, elements shown above other elements are positioned vertically above the other elements, in one example. As yet another example, shapes of the elements depicted within the figures may be referred to as having those shapes (e.g., such as being circular, straight, planar, curved, rounded, chamfered, angled, or the like). Further, elements shown intersecting one another may be referred to as intersecting elements or intersecting one another, in at least one example. Further still, an element shown within another element or shown outside of another element may be referred as such, in one example.

<FIG> shows a method <NUM> for operating a fastener system. The method may be implemented by any of the fastener systems and tooling apparatus or combinations of the fastener systems and tooling apparatuses described above with regard to <FIG>. However, in other examples, the method may be implemented by other suitable fastener systems and/or tooling apparatuses.

Next at <NUM> the method includes mating feet of a plurality of cantilever legs in a collet body with a plurality of openings in a sleeve in the fastener system. Such mating may include steps <NUM> and <NUM>. At <NUM> the method includes inwardly bending the feet and at <NUM> the method includes axially inserting the collet body into a central aperture in the sleeve.

At <NUM> the method includes inserting the stud through the center of the sleeve and imbedded collet body. Next at <NUM> the method includes attaching a bushing to an end of the stud. Attaching the bushing to the stud may include welding, press fitting, braising, adhesively bonding, combinations thereof, etc..

At <NUM> the method includes inserting the fastener system through bores in an upper and lower structure. At <NUM> the method includes threading a threaded section of the stud into an interior threaded section in one of the collet body and the sleeve. This threading may include steps <NUM>-<NUM>. At <NUM> the method includes, rotating the stud by a first amount so that the feet only partially extend through the plurality of openings. In this way, the stud may be partially threaded into the sleeve without pushing the feet out of the openings. It will be appreciated that the fastener system is in a disengaged configuration in step <NUM>.

At <NUM> the method includes rotating the stud by a second amount to apply an outward radially force on the cantilever legs to place the fastener system in an engaged configuration where the feet extend radially outward from the openings. Thus, the feet may clamp a lower structure while an upper section of the system, such as the stud head or auxiliary structure, may clamp an upper structure. At <NUM> the method includes rotating the stud by a third amount to create travel of the sleeve and the collet body. Next at <NUM> the method includes rotating the stud by a fourth amount to induce a desired clamping force. In this way, the fastener system may exert a targeted clamping force on the structures. It will be appreciated that the different stages of stud rotation may take place in succession (e.g., direct succession) during fastener engagement, in some examples.

At <NUM> the method includes unthreading the threaded section of the stud from the interior threaded section. In one example, when the stud is unthreaded the stud may freely rotate within the collet body and the sleeve. The free rotation of the stud prevents damage caused by unthreading of the stud from the sleeve to a greater degree than is necessitated. However, in other examples, the fastener system may not be designed to enable free spin of the stud. In such an example, the stud may be unthreaded until a spike in toque is sensed by a tooling apparatus or a person.

The technical effect of providing a fastener system with openings in a sleeve and cantilever legs in a collet body having feet that mate with the openings is the decoupling of shear stressed from the collet body to enable quick, efficient, and unencumbered clamping and unclamping of the fastener system.

The invention will further be described in the following paragraphs. In one aspect, a fastener system is provided. The fastener system includes a sleeve including a sleeve opening, a collet body at least partially enclosed within the sleeve, the collet body including, a crown having a crown opening, and a first cantilever leg extending from the crown and including a foot configured to mate with the sleeve opening when the fastener system is in an engaged configuration, and a stud extending through the crown opening and including a threaded section engaging with an interior threaded section in at least one of the collet body and the sleeve.

In another aspect, a fastener system is provided. The fastener system includes a sleeve including a plurality of sleeve openings, a collet body including, a crown having a crown opening, and a plurality of cantilever legs extending from the crown, each of the plurality of cantilever legs including a foot configured to mate with one of the plurality of sleeve openings when the fastener system is in an engaged configuration, and a stud extending through the crown opening and including a threaded section engaging with an interior threaded section in the sleeve, where, in the engaged configuration, the stud exerts an outward force on the plurality of cantilever legs to push a portion of each of the feet outside of the corresponding sleeve opening.

In another aspect, a method for a fastener system is provided. The method includes mating feet of a plurality of cantilever legs in a collet body with a plurality of openings in a sleeve, and threading a threaded section of a stud into an interior threaded section in one of the collet body and the sleeve.

In another aspect, a fastener system is provided. The fastener system includes a sleeve including a sleeve opening, a collet body at least partially enclosed within the sleeve, the collet body including, a crown having a crown opening, and a cantilever leg extending from the crown and including a foot configured to mate with the sleeve opening when the fastener system is in an engaged configuration, and an auxiliary structure at least partially extending around the sleeve having an inner diameter that is greater than an outer diameter of the sleeve.

In another aspect, a fastener system is provided. The fastener system includes a sleeve including a sleeve opening, a collet body at least partially enclosed within the sleeve, the collet body including a crown having a crown opening, and a cantilever leg extending from the crown and including a foot configured to mate with the sleeve opening when the fastener system is in an engaged configuration, and a stud extending through the crown opening and including a threaded section engaging with an interior threaded section in the sleeve and an unthreaded section positioned below the threaded section, the unthreaded section allowing the stud to spin freely when the threaded section of the stud is unthreaded from the interior threaded section of the sleeve.

In another aspect, a fastener system is provided. The fastener system includes a sleeve including a plurality of sleeve openings; a collet body including a crown having a crown opening, and a plurality of cantilever legs extending from the crown, each of the plurality of cantilever legs including a foot configured to mate with one of the plurality of sleeve openings when the fastener system is in an engaged configuration, and a stud extending through the crown opening and including, a threaded section engaging with an interior threaded section in the sleeve, and a head positioned external to a central aperture in the sleeve when the fastener system is in the engaged configuration, and a bushing coupled to an end of the stud.

In another aspect, a fastener system is provided. The fastener system includes a sleeve including a sleeve opening, a collet body at least partially enclosed within the sleeve, the collet body including, a crown having a crown opening, and a cantilever leg extending from the crown and including a foot configured to mate with the sleeve opening when the fastener system is in an engaged configuration, an auxiliary structure at least partially extending around the sleeve and including an upper stop and a lower stop limiting axial movement of a head of a stud positioned at least partially the auxiliary structure.

In another aspect, a fastener system is provided. The fastener system includes a sleeve including a sleeve opening, a collet body at least partially enclosed within the sleeve, the collet body including a crown having a crown opening, and a cantilever leg extending from the crown and including a foot configured to mate with the sleeve opening when the fastener system is in an engaged configuration, and an auxiliary structure at least partially extending around the sleeve and including a lower lip extending radially inward to retain a collar of the sleeve in an interior portion of the auxiliary structure.

In another aspect, a fastener system is provided. The fastener system includes a sleeve including a sleeve opening, a collet body at least partially enclosed within the sleeve, the collet body including, a crown having a crown opening, and a cantilever leg extending from the crown and including a foot configured to mate with the sleeve opening when the fastener system is in an engaged configuration, and an auxiliary structure at least partially extending around the sleeve and including a lower lip extending radially inward to retain a collar of the sleeve in an interior portion of the auxiliary structure, and a stud extending through the crown opening and including, a threaded section engaging with an interior threaded section in at least one of the collet body and the sleeve, and a head extending above the auxiliary structure.

In yet another aspect, a fastener system is provided. The fastener system includes a sleeve including a sleeve opening, a collet body at least partially enclosed within the sleeve, the collet body including, a crown having a crown opening, and a cantilever leg extending from the crown and including a foot configured to mate with the sleeve opening when the fastener system is in an engaged configuration, an auxiliary structure at least partially extending around the sleeve and including a lower lip extending radially inward to retain a collar of the sleeve in an interior portion of the auxiliary structure, and a stud extending through the crown opening and including, a threaded section engaging with an interior threaded section in at least one of the collet body and the sleeve, and a head that does not extend above the auxiliary structure.

In yet another aspect, a fastener system is provided. The fastener system includes a sleeve including a sleeve opening, a collet body at least partially enclosed within the sleeve, the collet body including, a crown having a crown opening, and a cantilever leg extending from the crown and including a foot configured to mate with the sleeve opening when the fastener system is in an engaged configuration, an auxiliary structure at least partially extending around the sleeve and including a lower lip extending radially inward to retain a collar of the sleeve in an interior portion of the auxiliary structure, and a stud extending through the crown opening and including, a threaded section engaging with an interior threaded section in at least one of the collet body and the sleeve, and an unthreaded section positioned below the threaded section and configured to allow the stud to spin freely when in a disengaged configuration.

In another aspect a fastener system is provided. The fastener system includes a sleeve including a sleeve opening, a collet body at least partially enclosed within the sleeve, the collet body including, a crown having a crown opening, and a cantilever leg extending from the crown and including a foot configured to mate with the sleeve opening when the fastener system is in an engaged configuration, an auxiliary structure at least partially extending around the sleeve and including, a lower lip extending radially inward to retain a collar of the sleeve in an interior portion of the auxiliary structure, an upper stop, and a lower stop limiting axial movement of a head of the stud positioned in an interior portion of the auxiliary structure, and a stud extending through the crown opening and including a threaded section engaging with an interior threaded section in at least one of the collet body and the sleeve.

In another aspect, a fastener system is provided that includes a sleeve including a sleeve opening, a collet body at least partially enclosed within the sleeve, the collet body including, a crown having a crown opening, and a cantilever leg extending from the crown and including a foot configured to mate with the sleeve opening when the fastener system is in an engaged configuration, and a stud extending through the crown opening and including a threaded section engaging with an interior threaded section in at least one of the collet body and the sleeve, where a bushing is coupled to a distal end of the stud or the stud includes an expanded diameter section at the distal end of the stud, and where the bushing or the expanded diameter section of the stud radially expand the cantilever leg when the stud is threaded into the interior threaded section in at least one of the collet body and the sleeve.

In any of the aspects or combinations of the aspects, the sleeve may include the interior threaded section.

In any of the aspects or combinations of the aspects, the stud may include a reduced diameter section positioned below the threaded section.

In any of the aspects or combinations of the aspects, an axial length of the reduced diameter section on the stud may be equal to or greater than an axial length of the interior threaded section of the sleeve.

In any of the aspects or combinations of the aspects, the collet body may include the interior threaded section.

In any of the aspects or combinations of the aspects, the first cantilever leg may include an outer surface in contact with an inner surface of the sleeve when the fastener system is in the engaged configuration.

In any of the aspects or combinations of the aspects, the fastener system may further include a bushing coupled to an end of the stud.

In any of the aspects or combinations of the aspects, a head of the stud may be positioned external to a central aperture in the sleeve when the fastener system is in the engaged configuration.

In any of the aspects or combinations of the aspects, when the fastener system is in the engaged configuration, a lower surface of a head of the stud may be in contact with an upper structure.

I n any of the aspects or combinations of the aspects, when the fastener system in the engaged configuration, an upper surface of the foot may be in contact with a lower structure.

In any of the aspects or combinations of the aspects, the first cantilever leg may bend radially inward in a neutral position.

In any of the aspects or combinations of the aspects, the sleeve may include a facetted collar spaced away from the sleeve opening.

In any of the aspects or combinations of the aspects, in a disengaged configuration the plurality of cantilever legs may be in neutral positions and in the engaged configuration the plurality of cantilever legs are in tensioned positions.

In any of the aspects or combinations of the aspects, advancing engagement between the threaded section of the stud and the interior threaded section may decrease a distance between an upper clamping surface and a lower clamping surface and where the lower clamping surface may be included in the feet and the upper clamping surface is included in the stud.

In any of the aspects or combinations of the aspects, the fastener system may further include an auxiliary structure at least partially extending around the sleeve.

In any of the aspects or combinations of the aspects, advancing engagement between the threaded section of the stud and the interior threaded section may decrease a distance between an upper clamping surface and a lower clamping surface and where the lower clamping surface may be include the feet and the upper clamping surface is included in the auxiliary structure.

In any of the aspects or combinations of the aspects, the auxiliary structure may include an upper stop and a lower stop limiting axial movement of a head of the stud positioned in an opening of the auxiliary structure.

In any of the aspects or combinations of the aspects, the auxiliary structure may include a stop having an inner diameter that is greater than an outer diameter of the threaded section of the stud and less than a diameter of a head of the stud.

In any of the aspects or combinations of the aspects, the auxiliary structure may include a lower lip extending radially inward to retain a collar of the sleeve in an interior portion of the auxiliary structure.

In any of the aspects or combinations of the aspects, where threading the threaded section of the stud into the interior threaded may include rotating the stud to apply an outward radially force on the cantilever legs and place the fastener system in an engaged configuration where the feet extend radially outward from the plurality of openings.

In any of the aspects or combinations of the aspects, mating the feet of the plurality of cantilever legs in the collet body with the plurality of openings in the sleeve may include inwardly bending the feet of the plurality of cantilever legs, and axially inserting the collet body into a central aperture in the sleeve.

In any of the aspects or combinations of the aspects, the method may further include unthreading the threaded section of the stud from the interior threaded section and freely rotating the stud within the collet body and the sleeve.

In any of the aspects or combinations of the aspects, the method may further include, prior to threading the threaded section into the interior threaded section and subsequent to mating the feet with the plurality of openings, attaching a bushing to an end of the stud.

In any of the aspects or combinations of the aspects, the stud may include a reduced diameter section positioned above the threaded section of the stud and where the threaded section has a larger diameter than the reduced diameter section is and is positioned closer to an end of the stud spaced away from a head of the stud.

In any of the aspects or combinations of the aspects, the fastener system may further include a locking ring positioned in a central aperture of the sleeve and at least partially circumferentially surrounding the stud and where the locking ring limits axial movement of the stud.

In any of the aspects or combinations of the aspects, the collet body may include a slit circumferentially positioned between two of the plurality of cantilever legs.

In any of the aspects or combinations of the aspects, the collet body may include a slit circumferentially positioned between the first cantilever leg and a second cantilever leg included in the collet body.

In any of the aspects or combinations of the aspects, the stud may include a reduced diameter section positioned above the threaded section of the stud and where the threaded section has a larger diameter than the reduced diameter section is and is positioned closer to an end of the stud spaced away from a head of the stud and where the reduced diameter section threadingly engages with the interior threaded section in the sleeve.

In any of the aspects or combinations of the aspects, the stud may include a reduced diameter section adjacent to the threaded section of the stud and where the stud freely rotates when the reduced diameter section is aligned with the interior threaded section in at least one of the collet body and the sleeve.

Note that the example control and estimation routines included herein can be used with various fastener system configurations. The control methods and routines disclosed herein may be stored as executable instructions in non-transitory memory and may be carried out by a tooling apparatus.

The specific routines described herein may represent one or more of any number of processing strategies such as event-driven, interrupt-driven, multi-tasking, multi-threading, and the like. As such, various actions, operations, and/or functions illustrated may be performed in the sequence illustrated, in parallel, or in some cases omitted. Likewise, the order of processing is not necessarily required to achieve the features and advantages of the example embodiments described herein, but is provided for ease of illustration and description. One or more of the illustrated actions, operations and/or functions may be repeatedly performed depending on the particular strategy being used. Further, the described actions, operations and/or functions may graphically represent code to be programmed into non-transitory memory of the computer readable storage medium in the fastener system and/or tooling apparatus, where the described actions are carried out by executing the instructions in a tooling apparatus and fastener system including the various components.

Claim 1:
A fastener system (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) comprising:
a sleeve (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) including a sleeve opening (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>);
a collet body (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) at least partially enclosed within the sleeve (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>), the collet body (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) including;
a crown (<NUM>) having a crown opening (<NUM>); and
a first cantilever leg (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) extending from the crown (<NUM>) and including a foot (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) configured to mate with the sleeve opening (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) when the fastener system (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) is in an engaged configuration;
and
a stud (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) extending or extendable through the crown opening (<NUM>) and including a threaded section (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) engaging or engageable with an interior threaded section (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) in at least one of the collet body (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) and the sleeve (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>).