Patent Publication Number: US-2023138175-A1

Title: Blind fastener

Description:
FIELD 
     This disclosure relates generally to fasteners. More particularly, this disclosure relates to fasteners such as blind fasteners for securing a plurality of workpieces together. 
     BACKGROUND 
     Blind fasteners are commonly used to secure a plurality of workpieces together when it is difficult or impossible to access a blind side of one of the workpieces. 
     SUMMARY 
     In some embodiments, a fastener includes a sleeve having a tubular portion including a first end and a second end opposite the first end. In some embodiments, the fastener includes a head located at the first end. In some embodiments, the fastener includes a deformable portion located at the second end. In some embodiments, the fastener includes a core pin having a first end and a second end opposite the first end of the core pin. In some embodiments, the core pin has an elongated shank portion between the first end of the core pin and the second end of the core pin. In some embodiments, the elongated shank portion includes a threaded portion proximate the second end of the core pin and a head at the first end of the core pin. In some embodiments, the sleeve is configured to receive the core pin. In some embodiments, the fastener is configured to secure a plurality of workpieces to one another. In some embodiments, the deformable portion of the sleeve is configured to be deflected in response to compression of the deformable portion by the head of the core pin, such that the deformable portion forms a flared connection that engages a surface of one of the plurality of workpieces. 
     In other embodiments of any of the foregoing fastener embodiments, the head of the sleeve of the fastener may additionally and/or alternatively include at least one recess. 
     In other embodiments of any of the foregoing fastener embodiments, the threaded portion of the core pin of the fastener may additionally and/or alternatively include thread-forming external threads. 
     In other embodiments of any of the foregoing fastener embodiments, the sleeve of the fastener may additionally and/or alternatively include an internal wall. In other embodiments of any of the foregoing fastener embodiments, the thread-forming external threads of the core pin may additionally and/or alternatively be configured to form corresponding internal threads in the internal wall of the sleeve. 
     In other embodiments of any of the foregoing fastener embodiments, a diameter of the head of the core pin of the fastener may additionally and/or alternatively be greater than an outer diameter of the sleeve. 
     In other embodiments of any of the foregoing fastener embodiments, the head of the core pin of the fastener may additionally and/or alternatively include a splined head. 
     In other embodiments of any of the foregoing fastener embodiments, the core pin of the fastener may additionally and/or alternatively include a drive portion configured to be engaged by a fastener installation tool. 
     In other embodiments of any of the foregoing fastener embodiments, the core pin of the fastener may additionally and/or alternatively include a breakneck groove located intermediate the drive portion and the threaded portion, and wherein the drive portion is configured to be separated from the elongated shank portion at the breakneck groove. 
     In other embodiments of any of the foregoing fastener embodiments, a diameter of the flared connection of the fastener may additionally and/or alternatively may be greater than 1.1 to 2 times an outer diameter of the tubular portion of the sleeve. 
     In other embodiments of any of the foregoing fastener embodiments, the core pin of the fastener may additionally and/or alternatively be composed of a first material and the sleeve be composed of a second material. In other embodiments of any of the foregoing fastener embodiments, the first material is harder than the second material. 
     In other embodiments of any of the foregoing fastener embodiments, the core pin of the fastener may additionally and/or alternatively be composed of stainless steel. 
     In other embodiments of any of the foregoing fastener embodiments, the core pin of the fastener may additionally and/or alternatively be composed of alloy steel. 
     In other embodiments of any of the foregoing fastener embodiments, the sleeve of the fastener may additionally and/or alternatively be composed of aluminum alloy. 
     In other embodiments of any of the foregoing fastener embodiments, the sleeve of the fastener may additionally and/or alternatively be composed of brass. 
     In other embodiments of any of the foregoing fastener embodiments, the sleeve of the fastener may additionally and/or alternatively be composed of copper. 
     In other embodiments of any of the foregoing fastener embodiments, the fastener may additionally and/or alternatively include the surface of the one of the plurality of workpieces being a blind side surface. 
     In other embodiments of any of the foregoing fastener embodiments, the deformable portion of the fastener may additionally and/or alternatively include a ramped portion. 
     In other embodiments of any of the foregoing fastener embodiments, the ramped portion of the fastener may additionally and/or alternatively include a first thickness located at the first end of the sleeve and a second thickness proximate to the second end of the sleeve. In some embodiments, the first thickness is greater than the second thickness. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       References are made to the accompanying drawings that form a part of this disclosure and that illustrate embodiments in which the invention described in this Specification can be practiced. 
         FIG.  1    is a side elevational view of a partially cross-sectioned blind fastener, according to some embodiments. 
         FIG.  2    is an enlarged view of detail A shown in  FIG.  1   , according to some embodiments. 
         FIG.  3    is an enlarged view of detail B shown in  FIG.  1   , according to some embodiments. 
         FIG.  4    is a side elevational view of the blind fastener shown in  FIG.  1    inserted into workpieces, according to some embodiments. 
         FIG.  5    is an enlarged view of detail C shown in  FIG.  4   , according to some embodiments. 
         FIG.  6    is an enlarged view of detail D shown in  FIG.  4   , according to some embodiments. 
         FIG.  7    is a side elevational view of the blind fastener shown in  FIG.  1    fully installed within the workpieces, according to some embodiments. 
         FIG.  8    is an enlarged view of detail E shown in  FIG.  7   , according to some embodiments. 
         FIG.  9    is an enlarged view of detail F shown in  FIG.  7   , according to some embodiments. 
     
    
    
     Like reference numbers represent the same or similar parts throughout. 
     DETAILED DESCRIPTION 
     In some embodiments, a blind fastener includes a deformable end capable of securing workpieces together, where the workpieces include a blindside workpiece in which a tool is not accessible or in which the workpiece is not visible. In some embodiments, the blind fastener is a pull-type blind fastener in which an installation force is directed toward a blindside of the blindside workpiece. 
     Referring to  FIGS.  1  through  3   , in some embodiments, a fastener  10  includes a core pin  12  and a sleeve  14  configured to receive the core pin  12 . In some embodiments, the core pin  12  is disposed within the sleeve  14 . In the some embodiments, the fastener  10  shown in  FIGS.  1  through  3    can be referred to as being in a pre-installation state. 
     In some embodiments, the core pin  12  includes an elongated shank portion  16  extending along a longitudinal axis L, the elongated shank portion  16  having a first end  18  and a second end  20  opposite the first end  18 . In some embodiments, the core pin  12  terminates in a head  22  at the first end  18 . In embodiments, the head  22  is an enlarged head. In some embodiments, the head  22  may include other shapes and sizes beyond that shown in  FIG.  1   . In some embodiments, the elongated shank portion  16  includes a substantially smooth cylindrical portion  24  adjacent to the first end  18 . In some embodiments, the elongated shank portion  16  includes a threaded portion  26  intermediate the first end  18  and the second end  20 . In some embodiments, the threaded portion  26  includes threads  28 . In some embodiments, threads  28  are thread-forming threads. In some embodiments, the elongated shank portion  16  includes a drive portion  30 . In some embodiments, a breakneck groove  32  is located between the threaded portion  26  of the elongated shank portion  16  and the drive portion  30 . In some embodiments, the head  22  has a diameter D1. In some embodiments, the core pin  12  includes a splined head. 
     In some embodiments, the core pin  12  is composed of steel. In some embodiments, the core pin  12  is composed of stainless steel. In some embodiments, the core pin  12  is composed of 300 series stainless steel. In some embodiments, the core pin  12  is composed of alloy steel. In some embodiments, the core pin  12  is composed of a corrosion resistant material. In some embodiments, the core pin  12  is composed of titanium alloys. In some embodiments, the core pin  12  is composed of nickel alloys. 
     In some embodiments, the sleeve  14  includes a tubular portion  34  having a first end  36  and a second end  38  opposite the first end  36 . In some embodiments, the sleeve  14  terminates in a head  40  at the first end  36 . In some embodiments, the head  40  is an enlarged head. In some embodiments, the head  40  protrudes from the accessible surface of the workpieces when the fastener  10  is installed therein. In some embodiments, the head  40  is flush with the accessible surface of the workpieces when the fastener  10  is installed therein. In some embodiments, the head  40  is a countersunk head. In some embodiments, the head  40  includes one or more recesses to prevent spinning of the sleeve  14  during rotation of the core pin  12  when installing the fastener  10 . 
     In some embodiments, the tubular portion  34  includes an internal smooth wall  42 . In some embodiments, the head  40  includes an internal smooth wall  44 . In some embodiments, the internal smooth wall  42  of the tubular portion  34  is aligned or integral with the internal smooth wall  44  of the head  40 . In some embodiments, the internal smooth wall  42  of the tubular portion  34  and the internal smooth wall  44  of the head  40  are sized and shaped to receive the elongated shank portion  16  of the core pin  12 . In some embodiments, the threaded portion  26  of the core pin  12  is located within the internal smooth wall  42  of the tubular portion  34  of the sleeve  14  adjacent to the head  40  of the sleeve  14  when the fastener  10  is in its preinstalled position. In some embodiments, the internal smooth wall  44  of the head  40  is configured to receive the threaded portion  26  of the core pin  12 , which will be described hereinafter. 
     In some embodiments, the sleeve  14  includes a deformable portion  46  located at the second end  38  of the tubular portion  34 . In some embodiments, the deformable portion  46  includes a ramped portion  48 A that is configured as later described to engage a ramped portion  48 B on the head  22  of the pin  12 . The ramped portion  48 A has a variable thickness. In some embodiments, the variable thickness can be a decreasing thickness so that a thickness T2 of the deformable portion  46  at the second end  38  is smaller than a thickness T1 of the deformable portion  46  closer to the first end  36 . In some embodiments, the deformable portion  46  has a diameter D2. In some embodiments, the diameter D2 is smaller than the diameter D1 of the head  22 . 
     In some embodiments, the sleeve  14  is composed of copper. In some embodiments, the sleeve  14  is composed of brass. In some embodiments, the sleeve  14  is composed of an aluminum alloy. In some embodiments, the aluminum alloy is a 6066 aluminum alloy. In some embodiments, the sleeve  14  is composed of stainless steel. In some embodiments, the sleeve  14  is composed of 300 series stainless steel. 
     Referring to  FIGS.  4  through  6   , in some embodiments, the fastener  10  is configured to secure a plurality of workpieces  50 ,  52  to one another, and is configured to be installed within aligned holes  54 ,  56  formed within the workpieces  50 ,  52 , respectively. In some embodiments, each of the holes  54 ,  56  has an inner diameter that is sized to accommodate the fastener  10 . For simplicity of this Specification, features of the fastener  10  already discussed will not be described in additional detail unless specifically referenced. 
     In some embodiments, with reference to  FIGS.  4  through  6   , the fastener  10  is partially installed within the workpieces  50 ,  52  In some embodiments, the workpiece  52  includes a blind side  58 . In some embodiments, the blind side  58  is difficult or impossible to access by a user with a fastener installation tool or otherwise or is difficult or impossible to view by the user. In some embodiments, the head  22  of the core pin  12  is adjacent the second end  38  of the sleeve  14 . In some embodiments, at least a portion of the head  22  abuts the second end  38  of the sleeve  14 . In some embodiments, the threaded portion  26  is positioned closer to the head  40  and plastically deforms the head  40  so that internal threads  60  of the sleeve  14  are formed by threads  28 . In some embodiments, the threads  28  of the core pin  12  threadedly engage the internal threads of the sleeve  14  to secure the core pin  12  to the sleeve  14 . 
     In some embodiments, to transition from the pre-installation state to the partially installed state, an installation tool can be used to engage the drive portion  30  and to rotate the core pin  12  relative to the sleeve  14 , causing engagement of the threaded portion  26  and the internal threads  28 . The engagement of the threaded portion  26  and the internal threads  28  forces the sleeve  14  to buckle and move toward the blindside workpiece  52  to form a flared connection  62  at the deformable portion  46 . The formation of the flared connection  62  secures the workpiece  52  and the workpiece  50  together. The fastener  10  is unable to move in either direction (e.g., toward the workpiece  50  or away from the workpiece  50 ) due to the presence of the head  40  on the workpiece  50  and the flared connection  62  on the workpiece  52 . 
     Referring to  FIGS.  7  through  9   , in some embodiments, the fastener  10  is configured to secure the workpiece  50  to the workpiece  52  when the fastener  10  is in an installed position. For simplicity of this Specification, features of the fastener  10  already discussed will not be described in additional detail unless specifically referenced. 
     In some embodiments, when the fastener  10  is in its installed position, the deformable portion  46  receives a compression force from the head  22  and the deformable portion  46  is resultingly deflected and deformed by the ramped portion  48 B of the head  22  to initiate formation of the flared connection  62 . In some embodiments, the flared connection  62  causes the deformable portion  46  to apply a force in a normal direction N1 to the workpiece  52 . In some embodiments, the head  40  applies a force in a normal direction N2 to the workpiece  50 . In some embodiments, the workpiece  50  and the workpiece  52  are secured to each other. In some embodiments, the drive portion  30  breaks and is removed from the fastener  10  at the breakneck groove  32 . In some embodiments, to contribute to the deformation of the deformable portion  46 , the core pin  12  and more particularly the head  22  are made of a harder material than the sleeve  14  and more particularly the deformable portion  46 . 
     In some embodiments, a size of the deformable portion  46  is selected so that a resulting diameter D3 of the flared connection  62  is greater than an outer diameter D2 of the sleeve  14 . In some embodiments, the diameter D3 is 1.1 to 1.7 times greater than the outer diameter D2. In some embodiments, the diameter D3 is 1.5 times greater than the outer diameter D2. 
     The terminology used herein is intended to describe embodiments and is not intended to be limiting. The terms “a,” “an,” and “the” include the plural forms as well, unless clearly indicated otherwise. The terms “comprises” and/or “comprising,” when used in this Specification, specify the presence of the stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, and/or components. 
     It is to be understood that changes may be made in detail, especially in matters of the construction materials employed and the shape, size, and arrangement of parts without departing from the scope of the present disclosure. This Specification and the embodiments described are examples, with the true scope and spirit of the disclosure being indicated by the claims that follow.