Breakaway W-base fastener

• US 7,878,749 B2
• Filed: 10/18/2007
• Issued: 02/01/2011
• Est. Priority Date: 01/05/2007
• Status: Expired due to Fees

• Current Assignee: Illinois Tool Works Inc.
• Original Assignee: Illinois Tool Works Inc.
• Inventors: Edland, David W.
• Primary Examiner(s): ESTREMSKY, GARY WAYNE
• Application Number:
  US11/874,311
• Publication Number:
  US 20080166206A1
• Time in Patent Office: 1,202 Days
• Field of Search: 411/508, 411/509, 411/41, 411/44, 411/48, 242/97
• US Class Current: 411/508
• CPC Class Codes: F16B 21/086 the shank of the stud, pin or spigot having elevations, ribs, fins or prongs intended for deformation or tilting predominantly in a direction perpendicular to the direction of insertion
• CPC Class Codes: F16B 5/065 the plates being one on top of the other and distanced from each other, e.g. by using protrusions to keep contact and distance
• CPC Class Codes: Y10T 24/309 Plastic type

Abstract

A w-base fastener that may be used in many applications, including numerous applications throughout the automotive industry, combines the functionality of a w-base fastener with the serviceability of other fasteners. The w-base fastener of the invention provides the ability to service the w-base fastener without damaging the panel or hole in which the fastener is inserted. This is accomplished by incorporating a break joint configured to break at a predetermined load. This break joint permits the fastener to be easily extracted when it breaks under the predetermined load. As the two sections of the fastener are separated, hooks on the fastener body engage tabs on the legs and pull the legs of the w-base fastener inward to prevent interference between the legs and the panel as the fastener is extracted from the hole.

Claims

1. A w-base fastener comprising:

a fastener body defining a first end and a second end,

a break joint formed in the body between the first end and second end, the break joint configured to break at a specified location when subjected to a predetermined pulling load so as to allow the first end and the second end to move a distance away from one another,

a plurality of legs attached to the second end of the body, the legs extending at an angle toward the first end, each leg terminating in a leg tab, and

a plurality of hooks disposed on the body between the break joint and the first end, the hooks including a portion configured to slidingly engage the leg tabs and pull them inward toward the fastener body when the break joint is subjected to the predetermined load, the hooks and the leg tabs being further configured and arranged so as to not engage one another until the break joint breaks.

2. The w-base fastener of claim 1 further comprising a head formed with the first end of the fastener body.

3. The w-base fastener of claim 2 wherein the head defines multiple head portions.

4. The w-base fastener of claim 3 wherein one of the multiple head portions defines a contact surface.

5. The w-base fastener of claim 1 wherein the fastener body further comprises a ledge disposed below the hook, the ledge configured to provide a positive stop for the leg.

6. The w-base fastener of claim 1 wherein the leg tab defines a notch formed at an upper end of the leg tab and the hook comprises a hook tab configured to engage the leg tab notch.

7. The w-base fastener of claim 1 wherein the leg tab is angled.

8. The w-base fastener of claim 1 wherein the hooks extend substantially perpendicular to the body.

9. The w-base fastener of claim 1 wherein the hook further comprises a lead-in element disposed on an upper surface of the hook to assist in the initial engagement of the leg tab.

10. The w-base fastener of claim 1 wherein the second end comprises opposing tapered portions.

11. The w-base fastener of claim 1 wherein the hook further comprises a lead-in element disposed on an upper surface of the hook to assist in the initial engagement of the leg tab.

12. A w-base fastener configured for insertion into a hole of a panel, the panel having a first side and a second side, the fastener comprising:

a fastener body defining a first end and a second end,

a head formed with the first end of the fastener body, the head adapted for placement adjacent to the first side of the panel and further configured to prevent the fastener from completely passing through the hole in which the fastener is mounted,

a joint formed in the body between the first end and second end,

a plurality of legs joined generally at the second end, the legs extending outwardly from the body at an angle and towards the first end, each leg terminating in a leg tab, the legs configured for engagement against the second side of the panel, and

a plurality of hooks connected to the body between the joint and the head, the hooks extending substantially perpendicular to the body and having a portion configured to slidingly engage the leg tabs and pull them inward toward the fastener body when a portion of the fastener body between the joint and the first end is moved away from a portion of the fastener body between the joint and the second end when the first end is caused to be separated from the second end at the joint.

13. The w-base fastener of claim 12 wherein the fastener body further comprises a ledge disposed below the hook, the ledge configured to provide a positive stop for the leg.

14. The w-base fastener of claim 12 wherein the leg tab defines a notch formed at an upper end of the leg tab and the hook comprises a hook tab configured to engage the leg tab notch.

15. The w-base fastener of claim 14 wherein the leg tab is angled.

16. The fastener of claim 14 wherein the second end comprises opposing tapered portions.

17. The w-base fastener of claim 12 wherein the head defines multiple head portions.

18. The w-base fastener of claim 17 wherein one of the multiple head portions defines a contact surface.

19. A w-base fastener comprising:

a fastener body defining a first end and a second end,

a head formed with the first end of the fastener body,

a joint formed in the body between the first end and second end,

a plurality of legs joined generally at the second end, the legs extending outwardly from the body at an angle and towards the first end, each leg terminating in a leg tab, wherein the leg tab defines a notch formed at an upper end of the leg tab,

a plurality of hooks connected to the body between the joint and the first end, the hooks extending substantially perpendicular to the body and defining hook tabs configured to slidingly engage the notch formed in the leg tabs and pull them inward toward the fastener body when a portion of the fastener body between the joint and the first end is moved away from a portion of the fastener body between the joint and the second end when the first end is caused to be separated from the second end at the joint, and

wherein the fastener body further comprises a ledge disposed below the hook, the ledge configured to provide a positive stop for the leg.