Other

Hi-shear Corporation

George S Wing

Harry L Bochman, Jr

Six lobes of a nut have axial surfaces falling on six tangent cylinders of equal radius and having axes lying on a right cylinder concentric with the axis of the nut. The surface of a second concentric right cylinder having a radius greater than the first defines furrows between the lobes. Successive lobes are tangent to an imaginary flat surface and the furrows are spaced away from the surface inside it.

Nut threaded fastener for applying a predetermined preload

The driver is a wrenching socket having rotatable balls mounted in the wall of an axial bore. The balls are retained in the wall swaged material of the wall. The driver applies torque to a collar to be set in a joint by the balls acting on the walls of axial troughs of the collar. At a predetermined pre-load, the balls fail bark material of the collar between the troughs and plow through such material to develop circumferential furrows after which torquing ends.

Ball driver for a threaded collar

An extended counterbore nut has a nut body and an attached collar extending from counterbore in the nut body. The bore of the collar is about equal in diameter to the major diameter of the thread of the bolt used with the nut so that the collar aligns the bolt and nut for threading. At a predetrmined axial load, the collar releases from the nut body and enters the counterbore, shortening the nut.

Extended counterbore nut

A threaded fastener joint is proofed by a wrenching washer between the fasteners of the joint and the work. The wrenching washer has the clamp-up load applied by the fasteners to the work applied through it. After an attempt to make the joint, the wrenching washer is torqued to determine whether it turns on the work at an applied torque below some predetermined proofing torque. If it does not, the joint is satisfactory; if it does, the joint is unsatisfactory.

Process for proofing a threaded joint

A modified buttress thread has a root diameter equal to substantially .sqroot.0.7 of the core diameter with a pitch substantially equal to 1/6 of the core diameter. The thread root extends parallel to the axis of the fastener as a surface and transitions into the thread form at radii at both the load-bearing and trailing flank of the thread. The thread at its maximum diameter has a flat equal to about 0.16 of the pitch. In the fastener system the axial length along a thread form of the collar at radial locations corresponding to the locations on a mating pin are inversely proportional to the strength of the materials of the collar and the pin, for example, when the collar is aluminum and the pin is titanium the lengths are in the ratio of 60:40.

Thread form and fastener system using the form

Axially-extending troughs in a bark of an internally threaded collar receive setting balls of a driver that apply a torque to the collar through the balls bearing on the walls of the troughs. At a predetermined preload, the balls fail the bark and plow through it to develop circumferential furrows, and the torgue application on the collar ends. A second torquing which balls at a different axial position fails the bark again at the same pre-load to compensate for any relaxation after the first torque application.

Process for setting a threaded torque-limited collar and pin joint

Axially-extending troughs in a bark of an internally-threaded collar receive setting balls of a driver that apply a torque to the collar through the balls bearing on the walls of the troughs. At a predetermined pre-load, the balls fail the bark and plow through it to develop circumferential furrows, and the torque application on the collar ends. A second torquing with balls at a different axial position fails the bark again at the same pre-load to compensate for any relaxation after the first torque application.

Process for making a joint with a torque-limited collar

A tri-lobular section of a bolt receives a mating tri-lobular bore of a washer to prevent the washer from rotating. Roll formed male threads on the tri-lobular section of the bolt receive a cooperating nut. The nut has a base shaped for wrench engagement, a thin walled barrel, a spring temper, and a threaded bore. The thread of the nut has two thread diameters: a large diameter thread in the base and a smaller diameter thread in the barrel continuing from the base thread; both thread sections have the same pitch. The barrel thread is substantially circular when relaxed. The barrel elastically flexes in response to the lobes of the nut as the lobes turn in the barrel, and when rotation stops, the barrel generally conforms to the tri-lobular shape of the bolt to form a thread lock, but the base does not.

Prevailing torque fastener assembly

Torque-limited collar

There is disclosed a very compact flat case for carrying prophylactics, such as condoms and the like. The overall dimensions of the case are approximately the same as a large coin. The case has flat top and bottom members which are hinged together with concentric cylindrical walls which support a resilient seal such as an O-ring. One or both of the mating walls are inclined to insure that sealing pressure is applied to the O-ring. The case has a closure which has a pair of detent balls, one each of each of the top and bottom members. The detent balls seat in mating recesses in the opposite member.

Hermetically sealed flat case

A tension limiter comprises a rigid body bearing a pair of deflector members which establish a bent path along the body. A stiffly bendable elongated rod extends along the bent path. The rod and the body are connected into a linkage so as to form a part of the linkage. When a tensile force above a datum value is applied to the tensioner the rod is pulled along the bent path, being bent as it moves, and this elongates the tensioner until the tensile force in the linkage is relieved to the datum value, thereby establishing the tension in the linkage at the datum value.

Tension limiter for linkages

A safety bolt having retention means to prevent its removal from a hole unless the retention means is released. The bolt includes a solid shank, and the retention means, which is outside the hole, has a slot with a pivoted latch means which is biased to move outside the diameter of the shank to prevent removal of the bolt. Access to the latch means enables it to be pivoted to a non-interfering position. The retention means can also form part of means to prevent a nut from being unthreaded from the bolt.

Safety bolt

A unitary lockable turnbuckle constructed from an elongated member, which is partially slit at two axially spaced-apart locations so as to form an interconnected barrel with a nut at each end. A thread is formed in each nut and the adjacent portion of the barrel, the thread at one end being of opposite hand from the thread at the other end. The slits leave reduced shear sections which break when the nuts are sufficiently torqued in opposition to the barrel. Preferably the width of the slit is reduced substantially to zero before the thread is formed.

Unitary lockable turnbuckle

There are disclosed nut locking assemblies comprising a washer adapted to slide over a spindle and be keyed to it, and a lock-ring to the rear of the washer and secured to the washer against relative rotation. The nut abuts the washer. The lock-ring is slidable axially so that in a forward position it is disengaged from the nut but in a rearward position serrations on the lock-ring engage corresponding serrations on the nut to lock the nut against rotation. An annular space between the washer and the lock-ring contains a resilient ring which can be strained to alter its diameter. In its normal unstrained condition this ring holds the lock-ring in its locking position. When it is desired to move the lock-ring to its unlocked position it is pushed forward to disengage the serrations of the lock-ring from those of the nut. This strains the resilient ring to a different diameter so that when the pressure is removed from the resilient ring it resumes its original unstrained diameter to push the lock-ring back into engagement with the nut, thereby locking it against rotation.

Growing community of inventors

Redondo Beach, CA, United States of America

George S Wing