Abstract: The preferred embodiment of the invention disclosed in this application includes a wrench, for example an operator powered wrench, for tightening a fastener assembly by the incremental application of tightening force. Also included is a control circuit for detecting a phenomena indicating that the joint assembly in which the fastener assembly is installed has been tightened to its yield point. The control circuit further includes checking means for determining that the fastener assembly is being tightened to assure that when the phenomena is detected, the joint assembly has been tightened to the yield point.

Abstract: An impact wrench having an adaptive control system for determining the yield point or some similarly significant point of a fastener assembly by detecting a signal representative of the peak deceleration of the hammer, one embodiment of which is the peak recoil value of the hammer after impacting with the anvil of the wrench, and a signal representative of the angular displacement of the output shaft of the wrench. Yield of the fastener is determined when the respective magnitudes of successive deceleration signals do not exceed the magnitude of a previously stored maximum deceleration signal by a predetermined fixed amount. Upon attaining the yield point or other similarly significant point, the wrench may be allowed to rotate the fastener an additional preselected number of degrees before shutting off.

Abstract: A blind fastener assembly includes a pin, an expander and a sleeve. The pin and expander may include, in one configuration, mating threads for drawing the sleeve axially over the expander toward the blind side of a workpiece, or the pin may be a pull-type wherein the portion of the pin opposite from the blind side end has pull grooves which are adapted to be gripped by a conventional pull gun. The sleeve is a tubular member having a portion of varying radial wall thickness between the ends thereof. The expander extends through aligned holes in the workpieces and has a tapered nose surface proximate the reduced thickness portion of the sleeve. When an axial force is exerted on the pin, the sleeve is forced over the tapered nose surface on the expander toward the blind side of the workpiece and is expanded in diameter.

Abstract: A tightening and control system is disclosed for automatically tightening a fastener to a predetermined tightened condition in a workpiece, where the fastener is of the type which exhibits more than one installation region on a graph of two tightening characteristics during a complete tightening cycle. Typical of such fasteners are thread tapping fasteners, such as thread-cutting or thread forming types, which first generate a mating thread in a workpiece material and thereafter are tightened in the workpiece to a predetermined load condition. Such fasteners typically exhibit a curve of two related input tightening characteristics, such as torque and rotation, having a thread forming region characterized by a generally linear portion followed by a marked drop off in the slope, an intermediate region having several possible characteristic shapes, and a tightening region having a somewhat similar shape to the thread forming region.

Abstract: A tightening and control system is disclosed for automatically tightening a blind fastener assembly to a desired tightened condition in a workpiece, where the assembly is of the type which exhibits more than one installation region on a graph of two tightening characteristics during a complete tightening cycle. Typical of such assemblies are the types which first form an outwardly flared bulb adjacent the blindside surface of a workpiece and thereafter are tightened against the blindside surface to a predetermined clamp load condition. Such fasteners typically exhibit a curve of two related input tightening characteristics, such as torque and rotation, torque and time, or force and stroke. Each curve has a bulb forming region characterized by a generally linear portion followed by a marked drop off in the slope, an intermediate region, and a tightening region having a somewhat similar shape to the bulb forming region.

Abstract: A blind fastener assembly includes a pin, an expander and a sleeve. The pin and expander may include, in one configuration, mating threads for drawing the sleeve axially over the expander toward the blind side of a workpiece, or the pin may be a pull-type wherein the portion of the pin opposite from the blind side end has pull grooves which are adapted to be gripped by a conventional pull gun. The expander extends through aligned holes in the workpiece and has a tapered nose surface at the blind side end adjacent a reduced thickness cylindrical portion which extends axially to a stop shoulder. The shoulder provides a transition to a normal thickness cylindrical portion which extends through the workpiece holes. The sleeve is a tubular member with a portion of its length having a normal radial thickness and a portion having a reduced radial thickness.

Abstract: A vibration resistant threaded fastener such as a set screw and method of forming the fastener wherein the load bearing flank of the thread surface of the screw is provided with a series of serrations. Each serration is formed with an inclined ramp terminating in a buttress forming a skewed angle with the radius of the fastener. The ramp surface is inclined in the direction of tightening the fastener so that the buttress presents a surface tending to act against rotation of the fastener to preclude its loosening. In forming the vibration resistant fastener a pair of flat thread roll dies may be used. Each die is provided with a mating segment near the end of the effective thread forming portion of the die having a configuration designed to impart the ramp and buttress serrations on the load bearing flank of the fastener rolled between the dies.

Abstract: A self-locking threaded fastener of the type having a resilient thermoplastic resin patch bonded to the thread surface and a method and apparatus for making such fasteners are disclosed. The fastener is heated to a temperature in excess of the plastic melting temperature by induction heating coils and powder is thereupon deposited on the surface of the threads over a predetermined area by gravity feed. Rolling pressure is then applied to the plastic material to form the patch, packing the material between the thread flanks and confining the height of the patch to a controlled radial height above the thread crests. The controlled radial height of the patch is within the normal envelope of the basic major diameter of the fastener thread.

Abstract: A retention and release mechanism utilizes a collet with deflectable fingers to allow assembly of the mechanism onto an object which is to be retained. Movement of the object toward the mechanism causes a force to be exerted on the bottom end of a plunger and movement of the plunger, which is coupled to a lockpin by a plurality of spherical balls and a split ring, from a released to a retained position. In the retained position, the balls secure the lockpin in a fixed position relative to the collet while mating tapered surfaces at the ends of the collet fingers and the lockpin cooperate to retain the object to which an expendable bushing has been attached, the bushing being part of the mechanism. To release the object, a force must be exerted on the top end of the plunger to move it to an axial position wherein the balls are released from their fixed position relative to the collet and the mating tapered surfaces move away from each other.

Abstract: A tool for attaching a support member formed with a hook member and a bendable tab member to a support post formed with a plurality of slots is disclosed. The tool is provided with a handle portion having an arcuate bending finger at one end and which is pivotally connected to a reaction finger having planar bearing surfaces. In use the reaction finger is placed in the slot in which the hook member is received and then the bending finger is inserted into the slot in which the tab member is received. Force is then applied to the handle portion which is applied to the tab member through the bending finger and which reacts through the reaction finger.

Abstract: A storage system in accordance with the preferred embodiment of the invention includes a support member formed with a first leg providing a track surface and a second leg extending at a generally right angle thereto and providing a guide surface. The second leg member is formed with a plurality of connecting means, one at each end of the support member, for securing the support member to adjacent support posts. The connecting means includes a hook member formed on the second leg and a tab member also formed on the second leg and forming an angle greater than 90.degree. with the portion of the second leg located between the hook member and the tab member. To assemble the storage system, the hook members are first engaged with slots in an adjacent pair of posts and the support member is then rotated so that the tab members pass into other slots in the post members. Thereafter, each of the tab members is bent toward the hook member so that it forms an angle less than 90.degree.

Abstract: A two piece grommet assembly comprising an inner and an outer member wherein each member has an enlarged head at one end formed to bear upon opposite sides of a panel skin. The outer member has a recessed area intermediate its ends and the inner member has a weakened section on the shank portion which is adapted to deform into the recessed section of the outer member upon the application of opposing axial force on the two members. The weakened section of the inner member is comprised of a reduced cross-sectional thickness portion which collapses upon the application of axial force, causing the reduced thickness portion to flow inwardly into intimate contact with the recess in the outer member, locking the members together in the panel skin.

Abstract: A meter for determining stiffness or torque gradient including, in one embodiment, a deflectable coupling connected between an output shaft and a power input shaft, sensing means for developing two separate series of signals representative of the displacement of the input and output shafts respectively, a comparator for determining from the two series of signals a function of the stiffness or torque gradient and, in another embodiment, including a single shaft having an input end and an output end, transducer means associated with the shaft for developing a signal representative of the torque being applied through the shaft, sensing means for developing a signal representative of the displacement of the shaft, and comparator means for determining from the two signals a function of the stiffness or torque gradient.

Abstract: A preferred embodiment of the invention disclosed herein relates to a method of and tightening system for tightening a joint assembly including a fastener system to a yield point of one of the members in the assembly. According to the method, torque is applied and rotation is imparted to a fastener member, and the torque and rotational displacement of the fastener are determined at predetermined increments of rotation for use in determining the area between successive increments of rotation under the Torque-Rotation curve which could be plotted. The incremental areas are compared to determine when some member in the joint assembly has been tightened to its yield point or some similarly significant point. The tightening system includes a wrench and a control system associated with the wrench including measuring systems for developing a first signal representative of the torque applied to the fastener and a second signal representative of the rotation of the fastener.

Abstract: The preferred embodiment of the invention disclosed herein relates to a method of and a tightening system for tightening a joint assembly including a fastener system to a yield point of one of the members in the assembly. According to the method torque is applied and rotation is imparted to a fastener member and the instantaneous slope of the Torque-Rotation curve which could be plotted is determined between successive increments of rotation of the fastener member. Each instantaneous slope is compared with the preceding instantaneous slope to determine the change in the slope of the curve. When the instantaneous slope of the curve decreases a predetermined consecutive number of times equal to a predetermined span of rotation divided by the interval between successive increments of rotation, tightening is discontinued.

Abstract: A blind fastener assembly includes, in one embodiment a pin, an expander and a sleeve. The pin and expander may include, in one configuration, mating threads for drawing the sleeve axially over the expander toward the blind side of a workpiece, or the pin may be a pull-type wherein the portion of the pin opposite from the blind side end has pull grooves which are adapted to be gripped by a conventional pull gun. The sleeve is a tubular member with a portion of its length having a normal radial thickness and a portion having reduced radial thickness comprising a reduced outer diameter over a portion of its axial length and a counter-bore along the same axial length adjacent one end of the sleeve. The expander extends through aligned holes in the workpieces and has a tapered nose surface proximate the reduced thickness portion of the sleeve.

Abstract: A quick-acting fastener assembly for securing a hinged cover to a storage box wherein the components of the fastener assembly are retained on the box and cover respectively when the fastener is not secured. The fastener assembly is self-actuatable without the need for any external tool, and the component parts are not loose and free to rattle in an unsecured position. The assembly includes a hollow stud member which has screw threads at both ends thereof, a securing nut assembly on one end, an adjusting nut assembly on the other end and a spring. The stud member is slidingly mounted through an opening in the box and includes a tab member carried thereon which restricts rotation of the stud relative to the box and also restricts axial movement of the stud in one direction. One end of the stud includes multiple lead threads which cooperate with the securing nut assembly to fasten the cover.

Abstract: In the preferred embodiment of the invention disclosed herein a lift apparatus includes a load carriage movable along a mast member by a hoist means including a cable supporting the load carriage and connected to a drive means. Also included is a safety brake including brake means operative to apply a braking force between the load carriage and the mast member and for supporting the load carriage on the mast member when the brake means is in its operative condition. In accordance with the invention, the brake means is controlled through an operating member which is actuated by either a first or second actuating means, each of which is independent of the other. The first actuating means is arranged to operate the brake means if the cable supporting the load carriage fails and the second actuating means is arranged to operate the brake means in response to an over-speed condition created by other failures in the hoist means.

Abstract: The invention disclosed herein relates to a fastener assembly and method of using same to preload a joint including a plurality of adjacent workpieces having aligned openings formed therein. The fastener assembly includes a pin member having an enlarged head and a shank located within the aligned openings in the workpieces and further includes a collar member having a deformable outer portion and a relatively hard inner portion located about a portion of the shank such that the inner portion is directly adjacent the shank portion. Also formed on the shank is a thread configuration adapted to cooperate with a complimentary thread configuration for snugging the workpieces together with a relatively light preload. After the joint has been snugged together, the collar member is crimped causing axial flow of material in the outer portion which reacts to stretch the pin member and induce a desired preload in the joint.

Abstract: A storage system in accordance with the preferred embodiment of the invention includes a support member formed with a first leg providing a track surface and a second leg extending at a generally right angle thereto and providing a guide surface. The second leg member is formed with a plurality of connecting means, one at each end of the support member, for securing the support member to adjacent support posts. The connecting means includes a hook member formed on the second leg and a tab member also formed on the second leg and forming an angle greater than 90.degree. with the portion of the second leg located between the hook member and the tab member. To assemble the storage system, the hook members are first engaged with slots in an adjacent pair of posts and the support member is then rotated so that the tab members pass into other slots in the post members. Thereafter, each of the tab members is bent toward the hook member so that it forms an angle less than 90.degree.