Zip fastener with emergency opening facility

• US 20060000065A1
• Filed: 06/24/2005
• Published: 01/05/2006
• Est. Priority Date: 07/02/2004
• Status: Active Grant

• Current Assignee: YKK Corporation
• Original Assignee: YKK Corporation
• Inventors: Davies, Mark, Akashi, Shunji, Takasawa, Shigeyoshi
• Granted Patent: US 7,337,508 B2
• Time in Patent Office: Days
• US Class Current: 24/401
• CPC Class Codes: A44B 19/06 with substantially rectangular members having interlocking projections and pieces
• CPC Class Codes: A44B 19/384 Separable slide fasteners with quick opening devices
• CPC Class Codes: Y10T 24/2536 having interlocking surface formed from single member with varying cross section

Abstract

In a zip fastener the elements (10) on one tape have a head which engages a shoulder (20) of an opposed element to limit out of plane movement. A small number of elements (30) have a head (38) which bears on a shoulder 46 when twisted in one direction but passes the shoulder (46) when twisted in the opposite direction to allow partial separation of the elements to create a point of weakness. The coupled elements can be peeled apart when sufficient pressure is applied to one side of the tape at the point of weakness, but the elements resist twisting when pressure is applied to the opposite side.

Claims

1. A zip fastener comprising a pair of tapes having a plurality of coupling elements provided on an edge of each tape, wherein a first element on one tape has a head which bears on a shoulder of an opposed element (which may be the same as the first element or may be a second element) on the other tape when urged in a first direction transverse to the plane of the tape, and passes the shoulder when urged in a second direction opposite to the first direction.

2. A zip fastener as claimed in claim 1, wherein the first element has a first head portion which, in use, engages between head portions of two adjacent opposed elements on the other tape to prevent separation of the tapes in the general plane of the tapes, the first head portion bearing on the shoulder provided on the opposed elements, and a second head portion which is smaller than the first head portion and passes the shoulders on the opposed elements.

3. A zip fastener as claimed in claim 1, wherein the elements of the fastener appear similar when viewed from one side of the fastener.

4. A zip fastener as claimed in claim 1, wherein at least two first elements are provided.

5. A zip fastener as claimed in claim 4, wherein the two elements are adjacent one another.

6. A zip fastener as claimed in claim 5 wherein at least three first elements are provided, two elements being adjacent one another on a first tape edge, and the third element being provided on the other tape edge and interlocking with the other two elements.

7. A zip fastener as claimed in any one of claim 1, wherein the elements are formed of plastics material and insert moulded on the tape edge.

8. A zip fastener as claimed in any one of claim 1, comprising a plurality of second elements is provided on an edge of each tape, each second element having a head which bears on a shoulder of an opposed element when urged in the first direction and the second direction.

9. A zip fastener as claimed in claim 8, wherein the majority of the fastener elements are second elements.

10. A zip fastener having a pair of fastener tapes and coupling elements provided on an edge of each tape, the coupling elements on one tape edge engaging with the elements on the other tape edge, wherein one of the coupling element is asymmetrical about the plane of the tape to provide reduced resistance to flexing between the engaged coupling elements in one direction transverse to the plane of the tapes at the region of the one coupling element relative to the resistance in the opposite direction.

11. A zip fastener as claimed in claim 10, wherein at least three asymmetrical elements are provided, the elements being positioned adjacent one another.

12. A zip fastener having means for preventing separation of the coupling elements when pressure is applied to the engaged elements in a first direction transverse to a plane of engagement of the elements, and means allowing separation of the elements when pressure is applied in the opposite direction.