Abstract:
In one embodiment, a device for installing a fastener to couple two or more members is disclosed. The device includes a tool head configured to couple to a power tool and a socket coupled to the tool head. The socket is configured to engage a nut component of the fastener for installation thereof, and a retainer is coupled to the socket. The retainer is configured to retain a portion of the nut component separated during installation of the fastener.

Description:
BACKGROUND 
     This disclosure relates generally to power tools and, more particularly, to the installation of threaded fasteners in aerospace and related industries. 
     One type of threaded fastener used in the aerospace industry is a frangible threaded fastener such as the Hi-Lok type fastener. Such fasteners are particularly adapted for fastening two or more panels or workpieces together in areas where limited access exists for installation tooling. At least some of such threaded fasteners include a pin or bolt component that has a head and an opposite threaded end, and a nut component that has an internally-threaded body portion and a torque-off drive nut portion. The pin or bolt component is inserted from the rear (relative to the tooling) of an assembly, and the body of the nut component of the fastener is preliminarily threaded onto the exposed threaded end of the pin or bolt component on a front side of the assembly. 
     Tooling is applied over the nut component to engage the torque-off drive nut portion of the nut component. The tooling substantially prevents the pin or bolt component from rotating while the nut component of the fastener is threaded to the pin or bolt component and until a predefined torque is reached. At the predetermined torque, the drive-nut portion of the nut component is separated from the threaded body of the nut component. As such, the drive-nut portion of the nut component may be lost or may fall inside the manufactured structure where it can be difficult to remove. 
     BRIEF DESCRIPTION 
     In one embodiment, a device for installing a fastener to couple two or more members is disclosed. The device includes a tool head configured to couple to a power tool and a socket coupled to the tool head. The socket is configured to engage a nut component of the fastener for installation thereof, and a retainer is coupled to the socket. The retainer is configured to retain a drive-nut portion of the nut component separated during installation of the fastener. 
     In another embodiment, a fastener retention system for use with a power tool is described. The system includes a socket coupleable to a tool head of a power tool, the socket configured to engage a nut component of a fastener for installation thereof. The system also includes a retainer coupled to the socket, the retainer configured to retain a drive-nut portion of the nut component separated during installation of the fastener. 
     In yet another embodiment, a method of installing a fastener including a bolt portion and a nut portion, the nut portion including a body portion and a drive portion, is provided. The method includes engaging the bolt portion with a pin to prevent rotation thereof, engaging the nut portion with a socket, and positioning at least a portion of the drive-nut portion within a retainer coupled to the socket. The method further includes rotating the nut component until the drive-nut portion shears off and retaining the drive-nut portion within the retainer. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates an exemplary frangible threaded fastener; 
         FIG. 2  illustrates an exemplary tool that may be used to install the fastener shown in  FIG. 1 ; 
         FIG. 3  illustrates an enlarged view of a portion of the tool shown in  FIG. 2  and taken along area  3 ; 
         FIG. 4  illustrates a cross-sectional view of the tool shown in  FIG. 3  and taken along line  4 - 4 ; 
         FIG. 5  illustrates a cross-sectional view of a portion of the tool shown in  FIG. 2  in a first position after installation of the frangible threaded fastener; and 
         FIG. 6  illustrates a cross-sectional view of the tool shown in  FIG. 4  in a second position; 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  illustrates an exemplary frangible threaded fastener  10 , that may be used to couple a pair of panels or workpieces  12  and  14  together. In the exemplary embodiment, fastener  10  includes a pin or bolt component  16  and a nut component  18 . Bolt  16  includes head portion  20  and a threaded portion  22 , and nut component  18  includes an internally-threaded body portion  24  and a torque-off drive-nut portion  26  that are spaced apart by a torque-off groove  28 . An Allen-type hex shaped recess  30  is formed in threaded portion  22  that is sized to receive the working end of an installation tool (not shown) during installation of fastener  10 . 
     During installation, bolt  16  is inserted through apertures  32  defined in panels  12  and  14 . Initially, threaded body portion  24  is manually threaded a few turns onto bolt threaded portion  22 . The working end of an installation tool (not shown) is applied to fastener  10  to rotate drive-nut portion  26 , while bolt  16  is held stationary, such that body portion  24  is driven down against panel  12  to form a clamping engagement with panels  12  and  14 . Drive-nut portion  26  separates from body portion  24  along torque-off groove  28  when a predetermined torque is applied to drive-nut portion  26  such that fastener  10  is coupled in clamping engagement with panels  12  and  14 . 
       FIGS. 2-4  illustrate an exemplary power tool or fastener installation tool  40  that includes a body  42 , a lever  44 , and a tool head  46 . Specifically,  FIG. 2  is a perspective view of power tool  40 ,  FIG. 3  is an enlarged view of section  3  of  FIG. 2 , and  FIG. 4  is a cross-sectional view of  FIG. 3  taken along line  4 - 4 . In the exemplary embodiment, body  42  includes a motor (not shown) that is driven by compressed air supplied through a pneumatic port  47 , and the motor energizes tool head  46  when lever  44  is actuated. Tool head  46  is coupled to body  42  via a support plate  48 . Spaced, parallel upper and lower head plates  50  and  52 , respectively, are secured against support plate  48  by bolts  54  and  56 . A drive gear  58  is rotatably coupled between plates  50  and  52 . In the exemplary embodiment, drive gear  58  includes a hex-shaped aperture  60  defined therein. Alternatively, aperture  60  may have any shape that enables power tool  40  to function as described herein. A socket  62  is coupled to drive gear  58  with a hex portion  64  that is sized and shaped to be at least partially inserted through hex aperture  60 . A retaining ring  65  facilitates locking socket  62  and a retainer  66  in position with tool head  46  and to restrict relative movement therebetween during a fastening operation. In the exemplary embodiment, power tool  40  transmits rotary motion through a gear train (not shown) to drive gear  58 , which provides rotary power to socket  62 . Alternatively, tool  40  may be a hand operated tool that transfers rotary motion by user. 
     In the exemplary embodiment, retainer  66  is coupled to socket  62 . Retainer  66  and socket  62  are substantially concentrically aligned. Retainer  66  includes an inner diameter that is slightly larger than an outer diameter of socket  62  to facilitate a tight engagement between retainer  66  and socket  62 . Alternatively, retainer  66  and socket  62  may have any other shape or orientation that enables power tool  40  to function as described herein. Retainer  66  substantially circumscribes socket  62  and includes a plurality of tabs  68  defined by slots  70  formed in retainer  66 . In the exemplary embodiment, retainer  66  includes four tabs  68 . Alternatively, retainer  66  may include any number of tabs  68  that enables retainer  66  to function as described herein. Each tab  68  extends below a lower end  72  of socket  62 , and a flange or collar  74  extends from each tab  68  inwardly past the inner diameter of socket  62 . As such, collar  74  is positioned to retain drive-nut portion  26  within retainer  66 , as is described in more detail herein. In the exemplary embodiment, retainer  66  is fabricated from a polymer material, and slots  70  enable tabs  68  to flex outwardly to facilitate removal of drive-nut portion  26 , as is described in more detail herein. Alternatively, retainer  66  does not include tabs  68  or slots  70  and is fabricated from any material that enables retainer  66  to function as described herein. 
     In the exemplary embodiment, a pin  76  is supported within tool head  46  by a slide-fit mounting in a first central bore  78  defined in socket  62 . Moreover, in the exemplary embodiment, central bore  78  has a substantially circular cross-sectional shape formed in socket  62  such that pin  76  is operable for relative movement with socket  62 . Pin  76  includes a first end  80 , an opposite second end  82 , and a shoulder  84  defined therebetween. First end  80  extends below socket lower end  72  and has a hexagonal shape that is complementary to recess  30  to facilitate a mating engagement with, and rotation constraint of, bolt  16 , as described in more detail herein. Shoulder  84  projects from pin  76  and is operable for relative movement within a second central bore  86  and a third central bore  88  formed within socket  62 . 
     In the exemplary embodiment, pin second end  82  extends above support plate  50  and includes an aperture  90  that is sized shaped to receive a portion of a biasing member, for example spring  92 . Biasing member  92  limits rotation of pin  76  and includes an anchor loop  94  that is retained by bolt  56 , an extension loop  96  that is spaced about bolt  54 , and a retention arm  98  that extends into aperture  90 . Biasing member  92  substantially prevents rotation of pin  76  and biases pin  76  toward an at-rest position during operation of power tool  40 . For example, when pin second end  82  is moved away from tool head  46 , biasing member  92  biases pin second end  82  toward tool head  46  into the at-rest position. Similarly, when pin first end  80  is translated away from tool head  46 , biasing member  92  biases pin first end  80  toward tool head  46  into the at-rest position. 
     In the exemplary embodiment, a handle  100  is slidably coupled to pin second end  82 . Handle  100  facilitates transfer of force to pin  76  and includes a body portion  102  and a cap  104  that enables pushing and pulling movement of pin  76  by a user. Body portion  102  includes a bore  106  that has a diameter that is slightly larger than the diameter of pin second end  82 , and a slot  108  that is formed therein. Slot  108  enables spring retention arm  98  to extend into aperture  90 , as is shown in  FIG. 3 . Slot  108  includes an upper transverse section  110 , an opposite lower transverse section  112 , and a vertical section  114  that extends therebetween. Upper transverse section  110 , lower transverse section  112 , and vertical section  114  are each larger in width than the diameter of retention arm  98  such that handle  100  can be rotated about or selectively moved along pin  76  to enable retention arm  98  to be positioned along any point of slot  108 . 
       FIGS. 4-6  illustrate the operation of installing fastener  10  with exemplary power tool  40 . Specifically,  FIG. 4  illustrates power tool  40  installing fastener  10 ,  FIG. 5  illustrates power tool  40  removed from the installation area of fastener  10  and in a first position, and  FIG. 6  illustrates power tool  40  in a second position to eject drive-nut portion  26 . As shown in  FIG. 4 , in the exemplary embodiment, bolt  16  is inserted through apertures  32  formed in panels  12  and  14 . Nut component  18  is manually threaded to pin threaded portion  22 , and tool head  46  is positioned against fastener  10  such that third central bore  88  of socket  62  extends about drive-nut portion  26 , and such that pin first end  80  is positioned within bolt recess  30 . Spring  92  biases pin  76  towards bolt  16  to maintain pin first end  80  within hex recess  30 . At this time, an operator forces tool head  46  against fastener  10  and actuates the motor (not shown) within power tool body  42 . The motor transfers rotary motion to drive gear  58  such that socket  62  is rotated and such that drive-nut portion  26  and body portion  24  are rotated until panels  12  and  14  are secured between body portion  24  and bolt head  20 . Nut component  18  shears along torque-off groove  28  and drive-nut portion  26  is separated from nut body portion  24  when a predetermined torque is induced to drive-nut portion  26 . The predetermined torque has not been induced in  FIG. 4 , but has been achieved in  FIG. 5 . 
     After fastener  10  is installed and drive-nut portion  26  is sheared from nut body portion  24 , power tool  40  is removed from fastener  10 , and drive-nut portion  26  is retained within socket  62  and/or retainer  66  by collar  74 , as shown in  FIG. 5 . More particularly, in the exemplary embodiment, an aperture  116  defined by collar  74  is sized smaller than the diameter of drive-nut portion  26  such that drive-nut portion  26  cannot fall through aperture  116  without assistance. 
     As shown in  FIG. 6 , after power tool  40  is removed from the installation area, a force F is applied to handle  100  generally in the direction of tool head  46 , which translates pin shoulder  84  towards drive-nut portion  26  retained within retainer  66 . Shoulder  84  then contacts drive-nut portion  26  and pushes it against retainer tabs  68 , which flex outwardly under the force application and enable drive-nut portion  26  to be selectively ejected from retainer  66 . In the exemplary embodiment, a user pushes handle  100 , which translates shoulder  84  and ejects drive-nut portion  26 . Alternatively, translation of handle  100  and/or pin  76  is automated in any manner that enables power tool  40  to function as described herein. For example, an electric motor (not shown) provides force F to translate pin  76  within socket  62 . In the exemplary embodiment, once drive-nut portion  26  is ejected from retainer  66  and force F applied to handle  100  is removed, spring  92  biases pin  76  to return to the position shown in  FIG. 5 . Alternatively, the user may apply a pulling force opposite force F on handle  100  to slide pin  76  and return shoulder  84  to the position shown in  FIG. 5 . 
     In the exemplary embodiment, the height position of handle  100  is adjustable to enable power tool  40  to fit into small installation spaces. As shown in  FIG. 3 , spring retention arm  98  is positioned within lower transverse section  112  of slot  108  such that handle  100  is locked in a telescoped first position. This position prevents drive-nut portion  26  from being prematurely ejected from retainer  66 , for example, if pin first end  80  is stuck or otherwise engaged within hex recess  30  when power tool  40  is removed from fastener  10 . To adjust the height of handle  100  to a lower, collapsed second position (not shown), handle  100  is rotated counterclockwise until retention arm  98  is positioned at the bottom of slot vertical section  114 . Handle  100  is then pushed downwards until retention arm is positioned at the top of slot vertical section  114 . Handle  100  is then rotated clockwise until retention arm  98  is positioned at the distal end of upper transverse section  110 , locking handle  100  in the collapsed second position, which provides power tool  40  with a smaller size profile. 
     An exemplary method of assembling a fastener retaining power tool is described herein. A fastener installation tool  40  is provided, which includes a body  42 , a lever  44 , and a tool head  46 . Tool head  46  includes a drive gear  58  having a hex aperture  60 , and drive gear  58  is driven by rotary motion provided by a motor (not shown) within body  42 . A socket  62  is provided having a hex portion  64 , and first, second and third central bores  78 ,  86  and  88 , respectively. Socket  62  is coupled to tool head  46  by inserting hex portion  64  into aperture  60 . A retainer  66  is provided having at least one tab  68  defined by slots  70 , and a collar  74  extending inwardly from tab  68 . Retainer  66  is coupled to socket  62  such that the inner diameter of retainer  66  is fitted against the outer diameter of socket  62 , and collar  74  is positioned below socket lower end  72 . A pin  76  is provided having a first end  80 , a second end  82  and a shoulder  84  therebetween. Pin  76  is slidably coupled to socket  62  within first central bore  78  such that pin first end  80  extends outwardly from socket  62  and shoulder  84  is positioned within second central bore  86 . A handle  100  is provided having a tubular body portion  102  and a cap  104 . Handle  100  is movably coupled to pin  76  by positioning body portion  102  over pin second end  82  such that the inner diameter of body portion  102  is fitted against the outer diameter of pin  76 , the inner diameter of body portion  102  sized to allow handle  100  to slide along and to rotate about pin  76 . Tool head  46  further includes a biasing member such as spring  92  that includes a retention arm  98 , which is at least partially inserted into an aperture  90  formed in pin  76 . 
     As described above, exemplary power tool or fastener installation tool  40  provides management of a fastener portion that is sheared off during installation of the fastener. Retainer  66  is easily assembled onto installation tool  40  and enables sheared drive-nut portion  26  to be retained by power tool  40  until selective ejection of the waste. In this way, unwanted foreign objects are prevented from falling into and/or getting stuck in surrounding structure, which can require time consuming and exhaustive efforts to remove the objects. Exemplary power tool  40  thereby facilitates the safe and secure removal of fastener waste from the installation area to a suitable disposal location. Moreover, collapsible handle  100  enables power tool  40  to be used for fastener installation in small spaces, particularly in aircraft applications. Thus, described herein is an improved fastener installation tool. 
     This written description uses examples to disclose various embodiments, including the best mode, and also to enable any person skilled in the art to practice the described embodiments, including making and using any devices or systems and performing any incorporated methods. The patentable scope is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.