Abstract: A method of measuring the load in a member subjected to longitudinal stress, a load measuring device and a fastener tightening device using the method of measuring, a load indicating member and a load indicating fastener for use in conjunction with the method of measuring, a method of making the load indicating fastener, a method of making the load indicating fastener, a method of tightening the load indicating fastener and a transducer for instrumenting a load bearing member are each disclosed and claimed. A thin piezoelectric sensor consisting of a piezoelectric film sandwiched between two thin electrodes is permanently mechanically and acoustically coupled to the upper surface of a member and is used to determine the length, tensile load, stress, or other tensile load dependant characteristic of the member by ultrasonic techniques.

Abstract: A self-locking fastener having a bearing surface comprising a plurality of sets of serrations arranged to penetrate a workpiece such that while a resistance to the loosening of the fastener from the workpiece is created the marring of the workpiece surface is minimized. Use of the fastener is particularly advantageous if the workpiece consists of soft materials such as cast-aluminum or non-heat treated carbon steels. Each set of serration, when viewed as a profile, includes a downwardly inclined surface, a relatively deeper serration and a relatively shallower intermediate serration. The intermediate serration controls the depth of the penetration into a workpiece.

Abstract: A method of tightening and a tightening system using the method. The method includes the steps of providing pulse with modulated waveforms from an inverter, driving an AC induction motor by the waveforms in a highspeed low torque mode or a low speed high torque mode or causing the motor to stop, by controlling the inverter to vary the pulse width of the waveforms, and driving a fastening device by the AC induction motor.

Abstract: A blind fastener assembly suitable for use in joint assemblies including advanced composite material workpieces. The blind fastener assembly includes a core pin having an enlarged head, an expander having a head and a tapered nose portion and being mounted to the core pin, and a frangible sleeve mounted to the core pin between the enlarged head and the expander. The blind fastener assembly is insertable through aligned holes in the workpieces so that the head of the expander abuts the accessible side of the workpiece. Relative longitudinal movement of the core pin and the expander nut causes the sleeve to expand over the tapered nose and to break into two pieces, one of the two pieces expanding over the other of the two pieces to provide a large bearing surface on the blind side of the workpieces.

Abstract: A backing fixture is arranged for use with a pull gun to crimp eyelet type inserts under extemporaneous field conditions. When the desired crimping force is less than the force output of the pull gun, the backing fixture is modified with a spring to limit the crimping force. By compressing the spring prior to crimping operations, its size is decreased and by incorporating means for varying the magnitude of pre-crimp spring compression, the crimping force is made adjustable.

Abstract: The torque and angular displacement transducers in a yield threshold controlled wrench apparatus are relocated to reduce the problems encountered therewith from the harsh physical environment experienced by such transducers in conventional designs. In one preferred embodiment, both the torque and angular displacement transducers are located at completely remote locations from the movable elements of the wrench mechanism and are each housed in a conventional hydraulic fitting to be more readily replaceable for maintenance purposes, as compared to the transducers of conventional designs.

Abstract: A blind fastener installation tool as well as a blind fastener and a core bolt for the blind fastener, both being adapted for use with the installation tool. The installation tool has coaxially disposed first and second tool engagement members each engageable at one of their ends, respectively, with a drive stem of a core bolt of the blind fastener, and a bearing surface forming element of the blind fastener, and an axial through passageway through the first tool member for removal of the drive stem from the tool at a location remote from the engagement ends of the tool engagement members. The core bolt has an elongated main body having a head at one end, a taper at the other end, a breakneck therebetween, and an elongated drive configuration extending along the entire portion of the core bolt between the breakneck and the taper.

Abstract: A self-locking fastener having a bearing surface comprising a plurality of sets of serrations arranged to penetrate a workpiece such that, while a resistance to the loosening of the fastener from the workpiece is created, the marring of the workpiece surface is minimized. Use of the fastener is particularly advantageous if the workpiece consists of soft materials such as cast-aluminum or non-heat treated carbon steels. Each set of serration, when viewed as a profile, includes a downwardly inclined surface, a relatively deeper serration and a relatively shallower intermediate serration. The intermediate serration controls the depth of the penetration into a workpiece.

Abstract: A set screw having a novel cup-point for engagement with a shaft or rod. The cup-point has knurling on a portion of its outer circumferential surface and is provided with a smooth frustoconical surface portion adjacent the knurling such that, in use, the smooth surface portion of the cup-point engages the surface of the rod or shaft before the knurling.

Abstract: A self-locking fastener having a bearing surface comprising a plurality of sets of serrations arranged to penetrate a workpiece such that, while a resistance to the loosening of the fastener from the workpiece is created, the marring of the workpiece surface is minimized. Use of the fastener is particularly advantageous if the workpiece consists of soft materials such as cast-aluminum or non-heat treated carbon steels. Each set of serration, when viewed as a profile, includes a downwardly inclined surface, a relatively deeper serration and a relatively shallower intermediate serration. The intermediate serration controls the depth of the penetration into a workpiece.

Abstract: An article storage and retrieval system which includes a continuous track and a continuous article storage carousel supported from the track. The article storage carousel is movable in a horizontal direction and contains a plurality of horizontally spaced and vertically extending baskets. Each basket has vertically spaced compartments. A motor is included to drive the article storage carousel around the track. An elevator is mounted in a fixed position adjacent to the outside of the track and includes a vertically movable article engager for placement in or withdrawal from a preselected compartment.

Abstract: A storage system utilizing both shelving and drawers mounted between supports in which the drawers may be locked individually or in concert for security purposes. The shelves are mounted to the support members above a number of drawers slidably mounted between the support members. A locking channel, adjustable in length to accommodate the number of drawers desired, is slidably mounted within a similarly adjustable housing at the rear of the storage system to engage operatively pawls mounted at the rear of the drawers. The locking channel is moved vertically by a spring-biased locking mechanism causing openings in the locking channel to come into proper alignment so that the locking channel engages the pawls to lock the drawers in concert or disengages from the pawls to unlock the drawers in concert. The angular design of the pawl arms allows drawers remaining open during the locking procedure to be individually closed and locked thereafter.

Abstract: A self-retained fastener including locking means provided near the end of the fastener first inserted through a hole in a workpiece wherein the locking means becomes operative after passing beyond the hole in the workpiece. The locking means comprises an annular groove near the end of the fastener having a configuration which increases radially outwardly from a point axially inwardly from the end of the fastener toward the end of the fastener. A spring ferrule member is engaged about the end of the fastener around the annular groove and includes a portion thereof which cooperates with the exterior surface of the workpiece and the annular groove on the fastener to oppose unintentional removal of the fastener from the workpiece once it has passed through the hole in the workpiece. The ferrule also serves as a removal tool for permitting removal of the fastener when desired.

Abstract: In combination with automatic storage and retrieval system having a continuous track which supports a continuous rotating storage unit to move therearound in a horizontal direction, the rotating storage unit including a plurality of horizontally spaced shelves arranged vertically into columns, a conveyor system mounted adjacent the rotating storage unit for moving storage bins towards and away from the rotating storage unit, and an elevator mounted in a fixed position between the rotating storage unit and the conveyor system; a platform mounted in the elevator for vertical movement up and down adjacent the rotating storage unit, an extraction and insertion arm assembly slidably mounted on the platform, the arm assembly including a pair of longitudinally disposed extractor arms having the forward ends extending towards the rotating storage units, a motor for driving the arm assembly in a horizontal direction towards and away from the rotating storage unit for bin placement in and withdrawal from a preselected

Abstract: Apparatus and method for tightening assemblies held together by threaded fasteners. Prior to tightening, the gradients of a selected number of possible torque-rotation curves for the assembly are established and stored along with the associated tightening torques required to induce a desired preload in the fastener when the assembly is tightened according to the selected torque-rotation curves. As torque and rotation are imparted to the fastener to tighten the assembly, the gradient of the actual torque-rotation curve through which the assembly is taken is calculated. The calculated gradient is compared with the stored gradients to derive that tightening torque which is associated with that stored gradient closest in magnitude to the calculated gradient. The derived tightening torque is used to control the torque applied to the fastener.

Abstract: Apparatus and method for tightening assemblies held together by threaded fasteners. The desired tightened condition is achieved by calculating the tightening torque required to induce a desired preload in the threaded fastener and comparing this calculated tightening torque with the torque being imparted to the fastener to tighten the assembly. When the two torques are equal, the torque imparted to the fastener is stopped. The tightening torque is calculated by identifying properly the relationship between the torque-rotation curve through which the assembly is taken as it is being tightened and the preload-rotation curve for the assembly.

Abstract: Apparatus and method for tightening assemblies held together by threaded fasteners. The desired tightened condition is achieved by calculating the tightening torque required to induce a preload in a fastener equal to or approximating a predetermined preload and comparing this calculated torque with the torque being imparted to the fastener to tighten the assembly. When the two torques are equal, the torque imparted to the fastener is stopped. The tightening torque is calculated by identifying properly the relationship between the actual torque-rotation curve through which the assembly is taken as it is being tightened and the theoretical torque-rotation curve for the assembly from which a theoretical tightening torque required to induce the predetermined preload is established.

Abstract: A pull-type blind fastener assembly includes a mandrel, expander, sleeve and lock collar. The expander extends through aligned holes in at least two workpieces, that are to be joined and has an enlarged head and a shank portion with a pair of conical tapered surfaces separated by a constant diameter surface thereon, adjacent the blindside end thereof. The tubular sleeve has a maximum thickness portion adjacent one end, an intermediate portion of medium radial thickness and a minimum radial thickness portion adjacent the other end. When an axial force is exerted on the mandrel by means of a conventional pulling tool, the minimum sleeve thickness portion is forced successively over the first and second conical expander surfaces where it is expanded, and a radially outwardly extending bulb begins to form at approximately the intersection between the minimum and medium thickness portion adjacent the other end.

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: Apparatus and method for tightening assemblies held together by threaded fasteners. The desired tightened condition is achieved by turning the threaded fastener through a precise tightening angle required to induce a predetermined preload in the threaded fastener and calculated from input parameters characteristic of the assembly being tightened and the predetermined preload. The tightening angle is measured from the onset of linearity of the preload-rotation curve for the assembly by sensing the onset of the substantially linear tightening portion of the torque-rotation curve through which the assembly is taken as it is being tightened.