US 5,199,834 A · Air bag stud

Abstract

A fastener which releasably retains a first member in relation to a second member. The fastener is frangible for fracture upon the application of a tensioning force thereto permitting the first and second members to which the fastener is engaged to be displaced relative to one another. The fastener, once fractured, is retained in the corresponding first and second members to which it was originally attached to prevent the generation of loose pieces. An installation tool is also provided for installing the fastener into the first and second members. The fastener includes a shank which fractures into a first and a second segment. A frangible portion of the fastener is spaced along the shank between the first and second segments and defines such segments for providing a predetermined fracture point. Non-planar engaging portions on the first and second segments retain the fastener in the corresponding first and second members once engaged therewith even after fracture of the fastener. The non-planar engaging portions also prevent the fastener from rattling while it is engaged with the members. The engagement portions include a thread which has a thicker base component and a generally flexible crest component.

Claims23

Dependent claims

A fastener for releasably retaining a first member in relation to a second member, said fastener being frangible for fracturing upon the application of a predetermined tensioning force thereto permitting first and second members to which said fastener is engaged to be displaced, said fastener segments being retained in the first and second member after fracture;

said fastener comprising a shank, a first and a second segment of said shank, frangible means spaced along said shank between said first and second segments for providing a predetermined fracture point between said first and second segments, helical engaging means on an outside surface of said first and second segments for engaging first and second members, respectively;
said first and second segments being individually captively retained in a first and a second member to which said fastener is engaged, respectively, after being fractured at said frangible means upon the application of a predetermined tensioning force thereto.

A fastener in combination with a first member and a second member for releasably retaining said first member in relation to said second member, said fastener being frangible for fracturing upon applying a predetermined tensioning force to at least one of said first and second members permitting displacement of said first and second members, said fastener being retained in said first and second members after fracturing;

said fastener comprising a shank, a first and second segment of said shank, frangible means spaced along said shank between said first and second segments for providing a predetermined fracture point between said first and second segments, helical engaging means on an outside surface of said first and second segments for engaging said first and second members, respectively;
said first and second segments being individually captively retained in said first and second members, respectively, after fracturing at said frangible means upon applying a predetermined tensioning force thereto.

A fastener in combination with an insertion tool for installing said fastener in a first and second member, said fastener releasably retaining a first member in relation to a second member when installed therein, said fastener being frangible for fracturing upon applying a generally tensioning force thereto releasing and permitting displacement of the first and second members, said fastener being retained in a first and second member after fracturing;

said fastener comprising a shank, a first and a second segment of said shank, frangible means spaced along said shank between and defining said first and second segments for providing a predetermined fracture point between said first and second segments, a cavity longitudinally projecting into said shank for reducing the cross sectional thickness of the shank and promoting fracture of said fastener into said first and second segments at said frangible means, helical engaging means on an outside surface of said first and second segments for engaging first and second members, respectively, said first and second segments being individually captively retained in a first and a second member, respectively, after fracturing at said frangible means;
said insertion tool comprising a shank receiving recess and a post extending from said recess, said post mating with said cavity and said recess receiving said shank for applying a force to said fastener for installing said fastener into a first and second member.

A method of using a fastener in combination with an insertion tool said fastener releasably retaining a first member in relation to a second member when installed therein, said fastener being frangible for fracturing upon applying a generally tensioning force thereto releasing and permitting displacement of the first and second members, said fastener being retained in a first and second member after fracturing;

said fastener comprising a shank, a first and a second segment of said shank, frangible means spaced along said shank between and defining said first and second segments for providing a predetermined fracture point between said first and second segments, a cavity longitudinally projecting into said shank for reducing the cross sectional thickness of the shank and promoting fracture of said fastener into said first and second segments at said frangible means, helical engaging means on an outside surface of said first and second segments for engaging first and second members, respectively, said first and second segments being individually captively retained in a first and a second member, respectively, after fracturing at said frangible means, a central axis extending longitudinally through said shank, a first bore projecting into a first member and a second bore projecting through a second member, said fastener being a push-in type fastener for insertion into a first and second bore in a first and second member by applying a force to said fastener generally along said central axis, said first segment being inserted through a second bore in a second member and into a first bore in a first member, said helical engaging means on an outside surface of said first segment engaging a first bore in a first member, said second member being inserted into a second bore of a second member and said helical engaging means on an outside surface of said second segment engaging a second bore in a second member;
said insertion tool comprising a shank receiving recess and a post extending from said recess, said post mating with said cavity and said recess receiving said shank for applying a force to said fastener for installing said fastener into a first and second member;
said method comprising the following steps:
positioning said fastener in alignment relative to a second bore in a second member;
inserting said post of said insertion tool into said cavity in said fastener;
mating said recess of said insertion tool with said shank of said fastener;
applying a force to said insertion tool along said central axis for engaging said fastener with a first and second bore in a first and second member;
removing said installation tool from said fastener.

5 more elements

said fastener comprising a shank, a first and a second segment of said shank, frangible means spaced along said shank between and defining said first and second segments for providing a predetermined fracture point between said first and second segments, a cavity longitudinally projecting into said shank for reducing the cross sectional thickness of the shank and promoting fracture of said fastener into said first and second segments at said frangible means, helical engaging means on an outside surface of said first and second segments for engaging first and second members, respectively, said first and second segments being individually captively retained in a first and a second member, respectively, after fracturing at said frangible means, a central axis extending longitudinally through said shank, a first bore projecting into a first member and a second bore projecting through a second member, said fastener being a push-in type fastener for insertion into a first and second bore in a first and second member by applying a force to said fastener generally along said central axis, said first segment being inserted through a second bore in a second member and into a first bore in a first member, said helical engaging means on an outside surface of said first segment engaging a first bore in a first member, said second member being inserted into a second bore of a second member and said helical engaging means on an outside surface of said second segment engaging a second bore in a second member;
said insertion tool comprising a shank receiving recess and a post extending from said recess, said post mating with said cavity and said recess receiving said shank for applying a force to said fastener for installing said fastener into a first and second member;
said method comprising the following steps:
positioning said cavity of said fastener over said post of said insertion tool;
mating said recess of said insertion tool with said shank of said fastener;
positioning said fastener on said insertion tool in insertion alignment with a second bore in a second member;
applying a force to said insertion tool generally along said central axis for engaging said fastener with a first and second bore in a first and second member;
removing said installation tool from said fastener.

5 more elements

A fastener in combination with a vehicle structure including a removable panel and an opening formed in said vehicle structure being covered by said panel, said fastener retaining said panel in a covering relation over said opening for concealing a deployable safety device, deployment of said safety device creating forces on said panel, said fastener being frangible for fracture upon application of said force to said panel for uncovering said opening, said fastener being retained in said panel and said vehicle structure after deployment of the safety device;

said fastener comprising:
a shank, a first and a second segment of said shank, an annular groove spaced along said shank between said first and second segments for providing a predetermined frangible fracture point between said first and second segments, helical engaging means on an outside surface said first and second segments for engaging said cover panel and said vehicle structure, respectively, said first and second segments being individually captively retained in said cover panel and vehicle structure, respectively, after fracturing at said annular groove upon the application of a generally tensioning force thereto upon deployment of said safety device.

Dependencies are inferred from the claim text.

Air bag stud

Life of this patent

Air bag stud

Life of this patent

Abstract

Claims23