Abstract: The coupling pin of the trailer of a tractor-trailer rig is provided with a theft prevention device for preventing the unauthorized coupling of unattended trailers. The device includes a truncated conical housing having a cylindrical sleeve which is secured to the inner base of the cone and is adapted to receive the coupling pin. The coupling pin is held within the sleeve by means of a pair of opposed, spring-biased locking jaws which normally protrude through a pair of opposed slots in the sleeve. In order to engage the reduced diameter portion of the coupling pin. The locking jaws are mounted on a pair of U-brackets. The brackets carry a pair of camming surfaces which are engaged by the wing cams of a key-operated lock. The lock is preferably recessed within the housing so that it cannot be sheared off during use. The invention has the additional utility of serving as a safety device for preventing the movement of a trailer during unloading operations.

Abstract: A locking fastener assembly is disclosed for securing electronic equipment or the like to a mounting bracket. The device includes a stud assembly comprising a threaded shank portion for passing through an opening in the bracket, and being threadingly received in an opening at the equipment. An enlarged head adjoins the shank and has a plurality of openings for receiving engaging pins from a cooperating tool. The spatial pattern of the openings (e.g. a spiral) define a plurality of different spacings between pairs of the openings. An annular freely rotatable collar surrounds the head and projects to at least cover the rim of the head, to prevent grasping of such head by a tool. A tool member is provided having a face opposable to the head, the face including a plurality of openings in a pattern corresponding to that on the head.

Abstract: A locking nut assembly comprises an axle nut, a resilient ring member and a cover member. The axle nut has a threaded bore at one end and a locking bore at the other end thereof. The threaded bore has a structural configuration which threadingly engages a bicycle axle. The outer surface of the axle nut has flat surface areas and an annular groove. The resilient ring member is disposed within the annular groove. The cover member is slidingly disposed over the outer surface of the axle nut. The cover member has a tapered, smooth outer surface and an end portion with a bore opening juxtaposed the locking bore of the axle nut. The use of the assembly prevents the untightening of the axle nut which holds the bicycle wheel in place on the bicycle frame.

Abstract: Apparatus which is mounted on a stud to prevent stud supported articles from inadvertently slipping off of the studs as well as to resist theft of such articles. The apparatus includes a two-piece body which is selectively connected together and such body defines an enlarged interior opening for receiving a portion of the stud and an opening of reduced diameter encompassing another portion of the stud.

Abstract: A lockable dip stick assembly for an oil filling spout comprises an elastomeric stopper disposed between an outer compression cap and an inner compression plate which carries a dip stick. A stud extends coaxially through the cap and stopper and threadably engages the compression plate. A bell housing supported for rotation on the outer end of the stud contains a key operated lock cylinder which has a bolt radially movable between uncoupled and coupled positions corresponding, respectively, to locked and unlocked positions of the lock cylinder. In a coupled position the bolt is connected in driving relation to a drive cup mounted in fixed position on the outer end of the stud and enclosed within the housing. Rotation of the key to and beyond an unlocked position causes rotation of the stud relative to the compression plate.

Abstract: A locking unit for immobilizing road vehicles to prevent their unauthorized removal comprises a sealed body which houses a movable locking member projecting from the housing and adapted for connection with a brake or clutch operating foot pedal or hand lever or with the control valve of an air-powered parking brake system. The sealed body also houses a key-released lock of the rotary barrel type having its plunger movable into locking engagement with the locking member manually without use of the key. The locking member may be a ratchet wheel engageable by a pawl which is pushed into engagement by the lock plunger acting on a spring. Further springs ensure the pawl being held clear of the wheel when the lock plunger is withdrawn. A modified form of the unit has a fixed jaw and a movable jaw by which the unit can be clamped around the stem of the draw-pin of a trailer vehicle and locked without using the key, thereby to prevent the hitch of a tractor from being coupled thereto.

Abstract: A lock assembly useful in coupling a tire assembly to a wheel which is locked and unlocked by a magnetic key.