Fastening device

• US 4,756,654 A
• Filed: 10/16/1986
• Issued: 07/12/1988
• Est. Priority Date: 06/13/1984
• Status: Expired due to Term

• Current Assignee: TRW Inc. (Northrop Grumman Corporation)
• Original Assignee: TRW Inc. (Northrop Grumman Corporation)
• Inventors: Clough, Melvyn J. L.
• Primary Examiner(s): WILSON, NEILL R
• Application Number:
  US06/915,894
• Time in Patent Office: 635 Days
• Field of Search: 411/182, 411/429, 411/431, 411/436, 411/437, 411/373, 411/377, 411/378, 411/527, 411/904, 411/906, 411/907, 411/508-510, 411/512, 411/369, 24/108, 24/662
• US Class Current: 411/437
• CPC Class Codes: F16B 37/0842 fastened to the threaded bolt with snap-on-action, e.g. push-on nuts for stud bolts F16B37/0857 takes precedence; snap-on-action of a pin, spigot, shaft or the like and a member surrounding it F16B21/06
• CPC Class Codes: F16B 37/14 Cap nuts; Nut caps or bolt caps

Abstract

A molded plastic female fastener component including an aperture having an entrance end for receiving a threaded stud or bolt. Within the aperture are retaining means in the form of an axially spaced series of flexible legs each of which extends about at least a portion of the inner circumference of the aperture to generally define a helical thread form. The legs have a cross-section which tapers from a relatively thick base to a thin outer end inclined in a direction away from the entrance of the aperture. The spacing between adjacent legs in the series is equal to the pitch of the threads of the associated stud. The resilient nature of the shape of the legs allows them to deflect over the threads during an axial "push-on" engagement but to latch under the threads to prevent axial disconnection except by an unthreading operation.

Claims

1. A fastener component for connection to a helically threaded male connecting member, said component comprising:

(a) a molded plastic body having a wall defining a generally cylindrical aperture having an entrance end opening to the exterior of said body for axiallly receiving said male connecting member;

(b) first and second diametrically opposed and longitudinally extending series of a multiplicity of axially spaced independently flexible leg members formed integrally with said body, each of said leg members in each series being spaced from the next adjacent leg member a distance equal to the pitch of said helically threaded male connecting member and having a tapered cross-section with a relatively thick base and a relatively thin free end and extending about at least a portion of the circumference of the interior of the aperture in a helical path corresponding to the helical threads on the male connecting member;

(c) each of said leg members being defined by a pair of surfaces inclined at angles in the range of 30 to 45 degrees in a first direction away from the entrance to said aperture and being resiliently deflectable independently of said wall in said first direction but resisting deflection in a second direction opposite said first direction; and

,

(d) wherein each of said leg members further have a generally transversely extending flat on their free ends and a length such that their free ends substantially reach the roots of the threads of said male connecting member such that upon attempted axial withdrawal of said connecting member said leg members latch into said roots and axial withdrawal can be effected only by permanently deforming said leg members.

2. The fastener component of claim 1 wherein each said first and said second series have a circumferential extend of less than 180°

.

3. The fastener component of claim 2 including openings extending into said body and intersecting said aperture, said openings having a longitudinal extend at least as great as the longitudinal extent of each of said series of leg members.

4. The fastener component of claim 3 wherein there are a pair of said openings located on diametrically opposite sides of said aperture intermediate said first and said second series of leg members.

5. The fastener component of claim 1 including a resilient skirt member formed about said entrance end opening of said aperture and having an outer end lying in a plane perpendicular to the axis of said aperture.