Phillips Plastics Corporation

Illinois Tool Works Inc.

Phillips Plastic Corporation

Richard J Schwind

Burnell J Wollar

Joseph Bart

Gregory O Beglinger

Edward P Massof

A universally self-aligned expandable nut including a head and a body moldable in a simple mold having a straight-line open and close action. The head includes an enlarged flange having a central opening through which a screw can pass. The body includes a shank connected to the flange having individual upper walls separated by axially extending upper slots and inner and outer surfaces parallel to a longitudinal axis defining a shank cavity. The upper walls have distal ends establishing a first fold line. The body also has individual tapered wall sections separated by axially extending lower slots aligned with the upper slots. The tapered walls each have an upper end connected to the distal end of an adjacent upper wall section, a lower end, and an inner surface that coacts with inner surfaces of adjacent lower walls to define a lower cavity. The lower wall inner surfaces terminate at a medial portion between the upper and lower ends establishing a second fold line. A tubular member extends upward into the lower cavity and has uninterrupted interior and exterior wall surfaces extending parallel to the longitudinal axis to define a first bore axially aligned with the central opening. The body further includes an insertion and extending axially away from the lower end, uninterrupted outside and inside wall surfaces extending parallel to the body axis and a second bore aligned with the first bore.

Plastic expansion nut

A molded plastic one-piece hollow expansion nut comprises an outwardly expandable shank which is insertable through a panel hole and a head at one end of the shank for engaging the panel surface. A screw-receiving bore extends axially through the nut and receives the threaded shank of a screw whose screw head bears against the nut head. The portion of the bore along which shank wall expansion occurs is cylindrical and of slightly larger diameter than the screw thread. The inmost end of the bore is of oblong cross-section and its minor axis is shorter than the diameter of the screw thread. A single screw-engaging thread in the cylindrical bore initially holds and guides the screw. The shank walls opposite the ends of the minor axis have oblique screw-thread receiving slots therethrough which define very sturdy damage resistant nut threads which engage the screw thread. Rotational insertion of the screw draws the insertion end of the nut shank toward the nut head and effects shank expansion to thereby secure the nut in the panel hole. In some embodiments, interengageable components on the nut and on the screw interengage to prevent further screw rotation after the nut reaches fully expanded condition. In some embodiments, ratchet teeth on the screw thread and nut slots engage to prevent screw removal.

Damage resistant plastic expansion nut and screw therefor

A two-piece fastener comprises a screw and a plastic nut for releasably securing together two apertured panels. The screw comprises a screw head and a threaded screw shank insertable in the aperture of one panel. The nut comprises a nut head, a nut shank insertable in the aperture of the other panel, and a bore extending through both the nut head and nut shank to receive the screw shank. The nut shank has an expandable portion, a screw-engaging portion, and a common wall therebetween. The bore has an unthreaded bore region through the nut head and through expandable nut shank portion, an intermediate bore region through the common wall and in a part of the screw-engaging nut shank portion, and a threaded bore region through the screw-engaging nut shank portion. The expandable nut shank portion comprises a plurality of thin, flexible, resilient walls, each connected between the common wall and the nut head. Each flexible wall has a parabolically shaped recess on its inner surface along which it can bend. Each adjacent pair of flexible wall is separated by a slit which extends axially from the common wall and through the nut head. A single thread on the wall of the intermediate bore region engages the screw thread to maintain the screw and nut in pre-assembled condition and to guide the screw thread into engagement with discrete screw-engaging thread sections formed in the threaded bore region.

Re-usable expandable plastic nut for two-piece fastener

A fastener for securing primary and secondary panels together comprises a molded plastic one-piece U-nut and a molded plastic screw. The nut comprises two plates, each having a plate hole therethrough, which face each other with their plate holes in registry and which are integrally and resiliently interconnected along one edge in spaced apart relationship. One plate supports on its outer side an integrally formed nut shank having an internally threaded bore in registry with the plate holes. The other plate supports on its innerside an integrally formed annular shaped sloped lock tab which surrounds its associated plate hole and holds the nut in place on the primary panel. The bore thread is formed in discrete thread sections and locking teeth are formed on the undersides of the bore thread sections. The screw comprises a threaded screw shank having a screw head at one end. The screw thread has locking teeth formed on the upper side thereof at intervals therealong. In use, the U-nut is slipped onto the edge of the primary panel so that its plate holes and shank bore register with an oversized panel hole inward of the panel edge. The panels are then placed face-to-face and the threaded screw shank is axially inserted through a hole in the secondary panel and through the plate holes in the U-nut.

Fastener with plastic U-nut

A reusable two-piece fastener for releasably securing together a plurality of panels which have aligned apertures therethrough comprises a body member and an associated externally threaded screw member. The body member, which is molded of resiliently flexible compressible plastic, comprises a head at one end radially expandable/retractable legs at the other end. A cylindrical bore extends inwardly from the head end of the body member. Screw-engaging internal female threads are integrally formed on the bore wall and are arranged in axially spaced apart sets therealong, each set including a plurality of thread sections, each of which sections extends around only a part of the circumference of the bore. These female threads are resiliently movable radially outwardly either because they are inherently compressible and flexible (one embodiment) or because they are formed on outwardly swingable bore wall portions (another embodiment). The screw member is axially and slidably insertable into the bore past the outwardly movable female screw-engaging threads to effect leg expansion and entrap the panels between the expanded legs and the body head. After such insertion, the female screw-engaging threads operatively engage the externally threaded screw member to permit only rotational removal thereof. Preferably, the thread on the screw member is discontinuous to prevent complete withdrawl of the screw member from the body bore.

Reusable two-piece fastener

In a two-piece plastic fastener, initially molded as a unit, one piece is a grommet having a head with a flat front surface and forwardly projecting legs defining a sidewardly and forwardly opening slot; the other piece is a pin receivable through the head and forwardly slidable in the slot to an operative position holding the front ends of the legs flexingly diverged. As molded, a front end portion of the pin is connected with the head by a frangible flashing. A forwardly opening radially extending groove in the front of the head, opening from one side of the slot, defines a substantially flat forwardly facing groove surface that is rearwardly offset from and parallel to the front surface of the head and is flush with the front end surface of the pin. Cooperating ridges on the grommet legs and the pin confine the latter to lengthwise motion between the legs. In the molding apparatus, an elongated core element, lengthwise movable in mold-opening and mold-closing directions, defines the groove, the front end surface on the pin, and the rear portion of the slot.

Two-piece plastic fastener and apparatus for molding same

An expansion rivet assembly comprises an expandable hollow plastic rivet and a plastic drive pin therefor. The rivet has a head and a shank which is insertable in aligned holes in workpieces to be joined. The drive pin has a head and a shank which is inserted in the rivet bore and adapted to be axially drawn into the rivet bore by a tool which causes the pin head to engage the insertion end of the rivet shank and effect outward expansion of the rivet shank wall and which also causes break-off of the superfluous projecting end of the pin shank at a break-away indentation formed in the pin shank. The pin shank has a groove near its head end which engages a reduced diameter bore portion in the rivet to temporarily hold the pin and rivet together prior to use. The pin shank also has serrations which engage another reduced bore portion in the rivet upon full pin insertion to hold the pin and rivet together permanently. The said other reduced bore portion is serrated to enhance engagement with the serrations.

Expansion rivet assembly

A plurality of roller assemblies are mounted on the side liner walls of the washing compartment of an automatic dishwashing machine to movably support a dishrack which is insertable and withdrawable from the compartment to facilitate loading and unloading. Each roller assembly comprises three rust and corrosion proof plastic components, including a stud, a bushing screwed onto the stud and a roller rotatably mounted on the bushing, and the roller assembly is secured to the liner wall by a metal screw which extends through a hole in the wall and engages the stud. A sealing gasket is disposed around the screw between the stud and the liner wall to prevent liquid in the compartment from reaching the hole and the screw. The stud has a screw-receiving threadable bore which is closed at one end so as to completely encapsulate the screw and prevent liquid from reaching it. The stud has an externally threaded shank which extends into a threaded bore in the bushing which is closed at one end. The bushing has a flared end, to prevent axial removal of the roller.

Roller assembly for dishwasher rack

A rotatably engaging head for a fastener for attaching a complementary panel member to a support member. The head includes a substantially flat underside and also includes a generally radially extending slit. One edge of the slit is connected to and defined by a lead-in tongue spaced above and generally parallel to the head. The tongue permits facile introduction of the head through an aperture in the panel, which aperture is smaller than the head. Extending from the head is a shank, for engagement of the support member to the panel member.

Rotatably engaging head for fastener

A two-piece plastic fastener has a sleeve-like body comprising forwardly projecting flexible legs and having a concentric radially enlarged head at its rear end. Longitudinal slots in the body define the legs and space them apart laterally. A cylindrical plunger, forwardly insertable in the body to an operative position at which it holds the legs forwardly diverged, has two radially outwardly opening circumferential grooves, one near its front end, the other near its rear end. At the rear end of each slot in the body is a detent lug that has its rear end integrally connected with the body to have its front end flexible radially outwardly. These lugs detent-wise engage in the front groove to define a projecting position of the plunger and in the rear groove to define its operative position. Lugs and grooves are so configured as to offer more resistance to rearward than to forward plunger displacement. A concentric head on the rear of the plunger, substantially larger than the body head, is forwardly concave to overlie and conceal the body head when the plunger is in its operative position.

Growing community of inventors

Akron, OH, United States of America

Richard J Schwind