Vsi Corporation

Other

Hi-shear Corporation

Fairchild Holding Corporation

Ronald W Batten

There is disclosed a method for the assembly of an aerospace fastener system of a torque limiting, frangible collar nut and pin in a non-interference fit application wherein the pin develops increased frictional resistance to rotation with increased torque loading applied to the fastener. In the method, the nut is run up on the pin while rotation of the pin is retarded by a key which has a limited rotational movement and which is restrained against rotation by a resilient spring force. The method is practiced with an improved L-head for a rotationally driven tool in which the key holder of the L-head has a limited degree of rotational moveability which is resilient restrained by a spring link which includes a cable which is passed about a stationary drum to provide a dampening of the spring force. The invention greatly extends the useful life of keys as the torsional loads transmitted to the keys are held within safe limits.

Stationary key mounting in fastener tool

There is disclosed an improvement to an elongated tool holder such as the tool holders used to secure the immobilizing key used in aerospace fasteners to enable easy ejection of keys which is stuck or jammed in the holder. In these tools, a key is received in a receptacle of a tool holder that is slidably received within an outer, rotationally-driven member which distally supports a socket for engagement with the nut of the fastener of an aerospace fastener. The key is used to immobilize the bolt for non-interference fit applications of the fastener. A slot is formed along the shank of the tool holder intersecting the tool receptacle adjacent its interior end to expose the received end of the key and thereby permit insertion of an ejection member or tool to forcefully eject a jammed key from the tool receptacle.

Tool holder with ejection slot

There is disclosed a power driven tool for the removal of locking collars of the frangible fasteners used in the aerospace industry. The tool has a drive motor and gear housing with a stationary sleeve which projects from the housing. Within the stationary sleeve are mounted a rotationally driven outer member that distally bears a lead screw and that slidably receives a stationary, telescoping inner member with a spring to bias the inner member into its extended configuration, and a detent to capture the inner member in its contracted, working configuration. A key holder is mounted on the end of the stationary inner member which has a hexagonally broached center bore that receives a key having has an annular groove which receives a detent ball that is secured by a sliding bushing which surrounds the key holder and a spring which biases the bushing into the detent position. The collet clutch has an internally threaded axial bore which is received over the lead screw of the rotational outer member, and is rotationally indexed to a surrounding collet sleeve. The collet sleeve is engaged through a unidirectional clutch to the stationary sleeve of the housing. When a key is to be replaced, the telescoping inner member is extended by releasing its detent, exposing the key holder to permit one to retract the key detent sleeve and free the key for removal.

Collet type fastener removal tool

A socket wrench with an ejector for severed collars of frangible fasteners has a conventional box ratchet wrench with a socket sleeve distally carried on the wrench body. The sleeve has a through aperture having internal flats and an internal lip at one end. The ejector member has an external diameter closely conforming to the internal diameter of the sleeve and slidably received therein. The cylindrical ejector has an annular shoulder intermediate its length and a ring permanently secured to its opposite end, with the sleeve lip captured between the ejector shoulder and ring. As the ejector is slidably mounted in the sleeve, it can be depressed into the socket, ejecting the threaded collar of the frangible fastener.

Hand wrenching tool

There is disclosed a tool for the removal of locking collars of the frangible fasteners used in the aerospace industry, particularly for removal of fasteners installed in close quarters such in a deep channel where conventional tools cannot grip the collar. The tool has a collet-type chuck to grasp the collar of the fastener and has a lead screw to lock the collet chuck about the collar and permit removal of the collar. For this purpose, the collet chuck has a cylindrical neck which is received within a sleeve. The lead screw is received in the opposite end of the collet sleeve and is threadably engaged in the internally threaded bore of the collet chuck member, preferably with left hand threads, and has a head with wrenching flats. The lead screw has a central axial through bore which receives a key member which is used to immobilize the stud or bolt of the fastener system. A disk member is slidably received within the collet sleeve to eject removed collars from the collet chuck member.

There is disclosed an easily releasable fastener which is specifically designed for high torque applications. The fastener comprises a slotted nut having at least two axial slots, and preferably no more than one of the slots extends completely through the body of the fastener. The slots divide the fastener into at least two segments which, in the preferred embodiment are retained together by the residual portions of the incomplete slots. Each of the segments has a flat surface for torque transmission and the assembly of segments is surrounded by a thin retainer band seated in an annular groove about the body of the fastener. The fastener is mounted within a retaining ring which has internal flats that coact with the flatted surfaces of the individual segments. The retaining ring has external wrenching flats to permit the application of the fastener to a standard bolt. The fastener is released by an extractor which has a cylindrical shroud to surround the retainer ring, with an annular lip at one end and a drive bolt at its opposite end. The annular lip of the shroud is placed beneath the annular edge of the retaining sleeve and the drive bolt is advanced against the upper surface of the segmented nut, thereby forcefully extracting the ring from the segmented nut and releasing the hoop tension about the nut, whereby the nut segments are spread outwardly, releasing the bolt tension.

Releasable high torque fastener

The invention is a wrenching tool useful for loosening the locking collars of frangible fasteners which are commonly used in the aerospace industry. The tool has a socket head with an end of reduced thickness to provide a land on which is pivotally received the jaw end of a handle. The through socket of the head is traversed by the vertical shoulder between the head and its reduced thickness end, thereby providing an open area to the socket. The jaw end of the handle projects into this open area to grasp items within the socket, such as the narrow wall of the locking collar of a frangible fastener. In this application, the jaw end of the handle can be placed flush against the surface of the workpiece, thereby firmly grasping even very narrow locking collars. The wrenching tool can also be used to apply a frangible fastener by inverting the tool and grasping the hex collar in its socket. If necessary, the wrenching tool is used with a hex key wrench to immobilize the fastener bolt during removal or application of the frangible fastener.

A fastener having an external threaded pin, and an internally threaded collar freely spinnable onto the pin so as to be set to a predetermined torque. After the predetermined torque is applied, the collar is dimpled (indented) to lock the collar to the pin. The thread can be smooth so the lock is a smooth frictional running lock, or can be interrupted so material of the collar at the indentation forms a physical lock with the interrupted thread. A tool is shown that can drive and indent the collar. A method for setting the collar is also disclosed.

Free spinning, self-locking threaded fastener, and method and tool for

The invention is a wrenching tool useful for installation of the frangible, or torque-limiting, fasteners which are commonly used in the aerospace industry. The tool has a head with a post that is seated in the wrenching ring of fastener and is pivotally mounted on the jaw end of a handle. The jaw end of the handle moves towards the post as the handle is pivoted on the head, and grips against the outside wall of the wrenching collar. If necessary, the wrenching tool is used with a hex key wrench to immobilize the fastener bolt during removal or application of the frangible fastener.

Hand wrenching tool for installation of torque limited fasteners

There is disclosed an easily releaseable, internally threaded fastener having at least one axial slot which extends substantially through the wall of the fastener. The external wall of the fastener is non-cylindrical, e.g. hexagonal, or three-lobed, to permit the application of a fastening torque to the fastener. The fastener is surrounded by a retainer sleeve having a mating, internal wall portion which provides hoop strength to the fastener. The retainer also has an annular recess in its internal wall whereby the retainer can be slid axially, or rotated, to release the fastener. The fastener assembly includes a metal spacer seated in each axial slot of the fastener to permit the even transmission of the fastener application torque. In preferred embodiments, the fastener is formed by cutting several axial slots through the body of the fastener, but terminating short of severing the threads, thereby providing a fastener which, when released by the retainer, will yieldingly fail, thus avoiding the mechanical shock of release which is experienced upon the release of separate fastener segments.

Easily releaseable fastener

There is disclosed an improved wrenching tool which utilizes readily removable key member that is axially restrained in a key holder of the tool member by a detent ball and that can be released from the tool by precisely aligning the key holder to the outer, rotationally driven socket member of the tool. This invention comprises a release mechanism to locate the key holder in the tool at the precise position where the detent ball is aligned with a ball cavity in the outer socket member, thus permitting lateral displacement of the detent ball, and releasing the central key member. Preferably the key release includes a knob on a shaft which extends through a sidewall of the tool housing and which internally supports a cam that is received in a cam guide on an axially sliding block which is secured in a subassembly to the key holder.

Wrenching tool

There is disclosed a removable torque-transmitting body, such as a key and methods for securing the key in, and releasing it from, a power assisted wrenching tool for the attachment of fasteners, particularly frangible fasteners, in loose and interference fit applications. The key has a main shaft portion with a distal, torque-transmitting head at one end, and an opposite end of reduced thickness and non-circular cross section, with a transverse groove therebetween. The wrenching tool has a subassembly of an outer socket member and an elongated key holder slidably mounted therein, under spring resistance, with a ball detent mounted in a cross bore in the key holder. The reduced thickness end of the key is inserted into the receiving keyway of the holder, and an axial force can be applied to seat the key, with the detent ball received in its transverse groove. Alternatively, the cross bore in the key holder can be aligned with a ball receptacle in the outer socket member, the spring resistance on the holder disengaged, and the key is then slipped into the key holder, and the spring resistance is released to lock the key in its holder. Once the ball is seated in the transverse groove of the key, the key cannot be extracted until the holder is aligned in its ball releasing position and the spring resistance on the holder is disengaged.

Removable key for wrenching tool

There is disclosed an improved power assisted wrenching tool for the attachment of fasteners in loose and interference fit applications, and particularly for use with frangible fasteners. The improvement comprises a readily removable key which is used to immobilize the bolt during attachment of a threaded fastener, typically in a loose fit application. The key is retained in a wrenching tool assembly by a detent ball which is positively locked in the center core of the holder member of the wrenching tool and can only be disengaged by the axial alignment of the holder and the socket drive members of this assembly. The tool is thus easily adaptable for the application of fasteners in either loose or interference fit applications.

Growing community of inventors

Torrance, CA, United States of America

Ronald W Batten