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 determining dynamic friction in a threaded joint and an associated tightening system for tightening such joints including threaded fasteners. A value representative of the coefficient of friction in the threaded joint is obtained by determining the gradient of a torque-rotation curve which could be plotted for the joint being tightened, and dividing this gradient by the product of the fastener pitch diameter and the tension rate of the joint. The desired tightened condition is achieved by computing the tightening torque required to induce a predetermined preload in the threaded fastener and comparing this computed torque with the instantaneous torque being imparted to the fastener. When the two torques are equal, tightening of the fastener is stopped.

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.

Abstract: A method and apparatus for tightening an assembly including a pre-load indicating fastener is disclosed. Pre-load indicating fasteners are generally tightened until a crushable element, forming a portion of the pre-load indicating fastener, is plastically deformed. The present invention permits such fasteners to be tightened until the crushable element of the fastener is completely deformed. This reduces the problem of relaxation generally associated with such fasteners. The present invention permits joints including such fasteners to be tightened by automatic tightening systems, if so desired. The assembly is tightened until the crushable element of the fastener is fully plastically deformed and elastic deformation of the joint has commenced. Sensing means are provided in the automatic tightening system to enable detection of this point and to automatically stop the tightening system when this point is reached.

Abstract: A power tool speed and torque control mechanism is disclosed. An improved clutch assembly is provided for power tools of the type having a high speed/low torque mode for rapidly engaging a threaded fastener and a low speed/high torque mode for tightening the fastener. The clutch assembly includes a wrap spring clutch having two springs.

Abstract: A quick-acting panel fastener assembly for joining a panel to a sub-structure is disclosed. The fastener assembly includes a sleeve bolt, a grommet assembly which is attached to the panel and a receptacle assembly which is attached to the sub-structure. The sleeve bolt passes through the grommet assembly and engages the receptacle assembly thereby joining the panel and the sub-structure. The grommet assembly includes a retainer ring which engages a groove in the sleeve bolt when it is in its withdrawn position so that the sleeve bolt is retained in the panel and remains in its withdrawn position when the panel is disengaged from the sub-structure.

Abstract: A self-contained impact wrench having an adaptive control system for determining the yield point or some similarly significant tightened condition of a fastener assembly by detecting a signal representative of the forward rotation angle of the fastener assembly is disclosed. One embodiment utilizes a computed signal of time over a fixed interval of forward rotation angle, as an estimate of the torque applied by the impact wrench, and the torque estimate vs. rotation angle curve is differentiated to obtain the gradient thereof. Successive gradient values are stored and compared, and when the present gradient value has attained a predetermined relationship relative to a stored value of a gradient in a tightening region of the curve, further tightening of the fastener assembly is discontinued. This ensures that the yield point or other similarly significant tightened condition of the assembly has been reached.

Abstract: A triangle waveform having substantially linearly sloped, gradually increasing and decreasing edges and having a frequency nf is generated from an n-phase sine wave signal, each phase having a fundamental frequency f. A segment of any of the n-phases of the sine wave is detected when that segment is within a predetermined angular amount from a reference crossing level, such as the zero crossing of the sine wave signal. Successive ones of the detected segments are selected to synthesize the triangle waveform. In the preferred use of this invention, the triangle waveform is compared to a reference signal, such as the sine wave signal from which the triangle waveform is generated, this reference signal having a controllable frequency and amplitude. Pulse transitions are generated at the intersection of the triangle waveform and each of the respective phases of the reference signal.

Abstract: A fastener which includes an unthreaded bolt member having two groups of grooves formed therein is disclosed. All the grooves within each group have the same depth. The group of grooves furthest from the workpiece have a greater depth than the group of grooves adjacent to the workpiece, thus permitting a more uniform load distribution along the shank of the bolt.

Abstract: A fatigue resistant bolt, and method for making same, is disclosed. Bolts which are tightened to very high loads and are subjected to a dynamic environment are particularly subject to fatigue failure. It has been found that a bolt with fatigue resistant properties may be manufactured if its threads are formed while it is subjected to its design load. In another embodiment of the invention it has been found that the fatigue properties of the fillet at the bolt head and shank juncture may be significantly increased if the fillet is cold worked while the bolt is subjected to its design load.

Abstract: A hand operated tightening system for tightening a fastener assembly to its yield point is disclosed. The system includes a wrench for applying torque to a threaded fastener and means for mechanically differentiating the magnitude of torque applied with respect to the degree of rotation of the fastener. This differential represents the slope of the torque-rotation curve of the particular fastener assembly being tightened and is a constant while in the elastic range. Means are provided to signal a change in the magnitude of the differential so as to indicate when the yield point of the assembly has been reached. In one embodiment, the differentiating means emits an audible signal which is used to indicate that the yield point has been reached.

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.