PATENT DOCUMENT

Publication Number: US-10709212-B1
Application Number: US-201615209308-A
Country: US
Kind Code: B1

Title: Magnetic closures

Abstract:
An item may be provided with a body that forms an enclosure. The body may have a body portion that opens and closes along a seam. An elongated magnetic fastener may run along the seam. The magnetic fastener may have first and second strips of elastomeric material on opposing sides of the seam. Magnetic interlocking elements may be partially embedded in the first and second elastomeric strips. The fastener may be formed by injecting uncured elastomeric material having unmagnetized magnetic particles into a mold. While in the mold, a magnetic field may be applied to magnetize the magnetic particles and to align the magnetic particles into magnetized structures. After forming the magnetized structures within the elastomeric material, the elastomeric material may be cured. Once removed from the mold, portions of the elastomeric material may be removed to expose the magnetized structures, which may subsequently be shaped into interlocking fastener elements.

Claims:
What is claimed is: 
     
       1. An apparatus, comprising:
 a body having an interior and having a body portion that opens and closes along a seam to provide access to the interior from outside the body through an opening in the body; and 
 a fastener having a slider that moves up and down the seam to open and close the seam, wherein the fastener comprises:
 a first strip of elastomeric material that extends continuously along a first side of the seam, 
 a second strip of elastomeric material that extends continuously along a second side of the seam, 
 a first group of magnetic elements each having a first portion that is embedded in the first strip of elastomeric material and a second portion that protrudes out of the first strip of elastomeric material, and 
 a second group of magnetic elements each having a third portion that is embedded in the second strip of elastomeric material and a fourth portion that protrudes out of the second strip of elastomeric material and that interlocks with an associated one of the magnetic elements in the first group. 
 
 
     
     
       2. The apparatus defined in  claim 1  wherein the body portion comprises a layer of fabric. 
     
     
       3. The apparatus defined in  claim 2  wherein the layer of fabric has first and second edges on the first and second sides of the seam and wherein the first strip of elastomeric material extends along the first edge of the fabric and the second strip of elastomeric material extends along the second edge of the fabric. 
     
     
       4. The apparatus defined in  claim 3  wherein the layer of fabric forms part of a bag. 
     
     
       5. The apparatus defined in  claim 3  wherein the layer of fabric forms part of a garment. 
     
     
       6. The apparatus defined in  claim 1  wherein the first group of magnetic elements are magnetically attracted to the second group of magnetic elements. 
     
     
       7. The apparatus defined in  claim 1  wherein the first and second groups of magnetic elements form interlocking zipper teeth. 
     
     
       8. The apparatus defined in  claim 1  wherein the elastomeric material comprises silicone. 
     
     
       9. The apparatus defined in  claim 1  wherein the magnetic elements comprise neodymium. 
     
     
       10. An item, comprising:
 fabric having first and second edges on either side of a seam; and 
 a zipper that opens and closes the seam, the zipper comprising:
 a first strip of elastomeric material along the first edge of the fabric and a second strip of elastomeric material along the second edge of the fabric; 
 a first magnetic element partially embedded in the first strip of elastomeric material and a second magnetic element partially embedded in the second strip of elastomeric material, wherein the first and second magnetic elements interlock with one another when the seam is closed and separate from one another when the seam is open; and 
 a slider that slides along the seam to interlock the first and second magnetic elements. 
 
 
     
     
       11. The item defined in  claim 10  wherein the first magnetic element comprises a recess and the second magnetic element comprises a protrusion that is received in the recess when the first and second elements are interlocked. 
     
     
       12. The item defined in  claim 11  wherein the first magnetic element extends continuously along a length of the first strip of elastomeric material. 
     
     
       13. The item defined in  claim 12  wherein the recess in the first magnetic element extends continuously along the length of the first strip of elastomeric material. 
     
     
       14. The item defined in  claim 10  wherein the first magnetic element is one of a plurality of first magnetic elements partially embedded in the first strip of elastomeric material and wherein the second magnetic element is one of a plurality of second magnetic elements partially embedded in the second strip of elastomeric material. 
     
     
       15. The item defined in  claim 10  wherein the elastomeric material in the first and second strips of elastomeric material comprises silicone. 
     
     
       16. The item defined in  claim 10  wherein the first and second strips of elastomeric material are molded to the fabric. 
     
     
       17. The item defined in  claim 10  wherein the first and second strips of elastomeric material are adhesively attached to the fabric. 
     
     
       18. The item defined in  claim 10  wherein the fabric encloses a cavity and wherein the seam provides access to the cavity when the first and second magnetic elements are separated from one another.

Description:
This application claims the benefit of provisional patent application No. 62/245,770, filed Oct. 23, 2015, which is hereby incorporated by reference herein in its entirety. 
    
    
     BACKGROUND 
     This relates generally to items formed from flexible material such as fabric-based items and, more particularly, to integrating magnetic closures into items formed from layers of flexible material. 
     Zippers are commonly used as closures for bags, garments, and other items formed from fabric. Some zippers are formed from discrete interlocking elements mounted on fabric tape. For example, plastic elements may be molded onto a fabric tape or metal elements may be crimped onto a fabric tape. In coil zippers, a coiled monofilament is processed to form interlocking teeth. Coil zippers can be sewn to a fabric tape. 
     Zippers on fabric tape can be sewn to pieces of fabric or layers of other flexible materials such as leather or plastic. The pieces of fabric or other flexible material may form portions of a garment, the sides of a bag, or other items that use zippers. 
     Conventional zippers mounted on fabric tape can be unsightly. The tape on which the zipper is mounted may be too soft or too stiff relative to the fabric or other flexible material to which the tape is sewn, leading to wrinkles and other disruption to the flexible material when the zipper is used. Zippers may sometimes snag on portions of the tape or portions of the flexible material. Conventional zippers can also be cumbersome to use, often requiring more than one hand to open and close. 
     It would therefore be desirable to be able to provide improved closures for fabric, leather, and other layers of flexible material. 
     SUMMARY 
     An item such as a bag that encloses an interior cavity or a garment may be formed from a flexible layer having portions that are coupled with a zipper. The flexible layer may be formed from a fabric, a material such as leather or plastic, or other flexible material. 
     A zipper may be formed from magnetic elements that are attracted to one another. One side of the seam may have a first set of magnetic zipper teeth that attracts a second set of magnetic zipper teeth on an opposing side of the seam. 
     The magnetic zipper elements may be co-molded with an elastomeric material to form a flexible, robust seam. An uncured elastomeric material such as silicone may be placed in a mold. Unmagnetized magnetic particles may be embedded in the uncured elastomeric material. A magnetic field may be applied while the material is in the mold to magnetize the magnetic particles. The magnetized particles may then be aligned and bonded together to form magnetized clusters by adjusting the applied magnetic field. 
     Following magnetization and alignment, the elastomeric material may be cured. During the curing process, the clusters of magnetic particles may bond with surrounding elastomeric material to form a robust mechanical connection without airgaps. 
     After removing the mold, the elastomeric material and/or the magnetic clusters may be machined or otherwise shaped to form the desired interlocking geometry for the magnetic zipper. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  is a cross-sectional side view of an illustrative item with a zipper in a closed position in accordance with an embodiment. 
         FIG. 1B  is a cross-sectional side view of the illustrative item of  FIG. 1A  with the zipper in an open position in accordance with an embodiment. 
         FIG. 2  is a diagram of an illustrative zipper with discrete elements in accordance with an embodiment. 
         FIG. 3  showing how magnetic material may be co-molded with an elastomer and magnetized to form magnetic elements of a desired shape in accordance with an embodiment. 
         FIG. 4  is a perspective view of a portion of an illustrative closure having magnetic elements partially embedded in an elastomer in accordance with an embodiment. 
         FIG. 5  is a cross-sectional side view of an illustrative magnetic closure in which a protrusion on one side of a seam is received by a recess on an opposing side of the seam in accordance with an embodiment. 
         FIG. 6  is a perspective view of an illustrative magnetic closure in which a groove on one side of a seam receives an elongated rail on an opposing side of the seam in accordance with an embodiment. 
         FIG. 7  is a perspective view of an illustrative magnetic closure in which a groove on one side of a seam receives a individual protrusions on an opposing side of the seam in accordance with an embodiment. 
         FIG. 8  is a perspective view of an illustrative magnetic closure in which recesses of individual elements on one side of a seam receive respective protrusions on an opposing side of the seam in accordance with an embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Magnetic material may be used in forming electronic devices, may be used in forming accessories such as covers, straps, and bags that are associated with electronic devices, may be used in forming fabric for electronic devices and accessories, may be used in forming fabric that is incorporated into seating, furniture, building structures, and other items, and/or may be used in forming other items. Configurations in which magnetic material is used in forming items based on one or more strands of magnetic material may sometime be described herein as an example. The strands of material may be monofilaments of material and/or may be multifilament strands such as strands of yarn. Strand-based items may be formed from intertwined strands such as woven strands, knitted strands, braided strands, strands that have been intertwined to form felt, or other intertwined strands (fabric, etc.). 
     Magnetic material may be magnetized to form permanent magnets. Permanent magnets may interact with each other. For example, permanent magnets may be arranged to attract each other or to repel each other. Electromagnets may be electrically configured to either attract or repel a permanent magnet. Unmagnetized magnetic material (e.g., ferromagnetic material or ferromagnetic material that has not been magnetized by application of an external magnetic field to form a permanent magnet) may also interact with permanent magnets and electromagnets. For example, a permanent magnet may attract a fabric or other structure formed from strands of unmagnetized magnetic material based on a rare earth alloy such as a neodymium alloy (e.g., NdFeB). 
     Zippers may include magnetic elements. Zippers may be used as closures in garments, bags, and other items. An illustrative item that may be provided with a magnetic zipper is shown in the cross-sectional side view of  FIG. 1A . As shown in  FIG. 1A , item  10  may have zipper  14 . Zipper  14  may have first and second opposing sets of interlocking teeth  16 . Item  10  may be a garment, a bag, or other item. Item  10  may include a body having an interior  18  and having a body portion such as body portion  12  that opens and closes along a seam to provide access to interior  18  from outside the body through an opening. Body portion  12  may be formed from one or more flexible layers of material and may sometimes be referred to as flexible layer  12 . For example, item  10  may be a bag in which flexible layer  12  surrounds and encloses interior cavity  18 . Other types of items may be provided with zippers such as zipper  14  if desired. The example of  FIG. 1A  is merely illustrative. 
     Flexible layers for item  10  such as flexible layer  12  may be formed from sheets of plastic, layers of fabric, leather, paper, or other flexible material. Fabric may be formed from strands of plastic, metal, other materials, and combinations of these materials. The strands may be monofilaments or multifilament strands and may include materials such a plastic, metal, and other materials. 
     As shown in  FIG. 1B , when zipper  14  is opened, zipper teeth  16  may be separated in directions  22  to form opening  20  in item  10  (e.g., an opening that allows objects to be inserted into interior cavity  18  or removed from cavity  18 ). Flexible layer  12  may form part of a garment, may form a sidewall in an item such as the sides of the bag of  FIG. 1B , may form part of a strap or band that is worn or is used to carry a bag, or may be used to form other portions of item  10 . 
     As shown in  FIG. 2 , zipper  14  may be formed from two interlocking sets of discrete zipper elements  24 . Zipper elements  24  may be formed from plastic, metal, other materials, or combinations of these materials. Zipper elements  24  may be formed along the edges of opposing portions of flexible layer  12 . Slider  26  may be moved along the length of zipper  14  using pull  28 . Slider  26  may contain a Y-shaped channel that can separate and join the two opposing halves of zipper  14  (e.g., the right and left sets of elements  24  in the example of  FIG. 2 ). Although the two halves of flexible layer  12  of  FIG. 2  are shown as being mated by bending flexible layer  12  within the plane of flexible layer  12 , other zipper geometries may be used (e.g., edge portions of layer  12  along zipper  14  may overlap each other, so that flexible layer  12  bends out of the plane of layer  12  when using zipper  14 ). 
     Zipper elements  24  may be partially embedded in an elastomeric material such as elastomeric strip  30 . Zipper elements  24  may be formed from magnetic material that is co-molded with elastomeric material  30  so that the magnetic material  24  is bonded at the atomic level with surrounding elastomeric material  30 . Integrating magnetic zipper elements  24  with elastomeric strip  30  in this way creates a robust closure that can open and close with minimum effort while providing a flexible seam between flexible layers  12  of item  10 . Zipper  14  may be attached to flexible layer  12  using molding techniques, crimping, sewing, adhesive-based mounting techniques, weaving, knitting, and other attachment techniques. 
       FIG. 3  is a diagram of illustrative steps involved in forming a magnetic closure of the type shown in  FIG. 2 . As shown in  FIG. 3 , uncured elastomeric material  30 ′ (sometimes referred to as a host material) may contain unmagnetized magnetic particles  32 ′ based on a rare earth alloy such as a neodymium alloy (e.g., NdFeB). Elastomeric material  30 ′ may be an uncured silicone material or other elastomer. At step  50 A, elastomeric material  30 ′ with embedded particles  32 ′ may be placed in a mold such as mold  46 . 
     After injecting material  30 ′ with particles  32 ′ in mold  46 , a magnetic field  36  may be applied to material  30 ′ and particles  32 ′ to create magnetized particles  32  (step  50 B). Magnetic field  36  may be applied using a matrix of electromagnets, using one electromagnet, or using any other suitable number or type of magnets. 
     Once magnetized, particles  32  may be positioned and aligned within material  30 ′ by appropriately controlling the strength and position of magnetic field  36 . Magnetic particles  32  are aligned to form magnetic clusters  34  in which adjacent magnetic particles  32  atomically bond with one another within elastomeric material  30 ′. In the example of  FIG. 3 , clusters  34  of bonded magnetic particles  32  form vertical columns within elastomeric material  30 ′. This is, however, merely illustrative. If desired, magnetic particles  32  may be aligned in a horizontal direction (e.g., to form one or more horizontal rows). In general, clusters  34  of magnetic particles  32  may have any suitable shape, size, density, pitch, or magnetic strength. If desired, magnetic particles  32  may be aligned to form a single cluster  34  that extends horizontally through material  30 ′. 
     Following magnetization and alignment of particles  32 , uncured elastomeric material  30 ′ may be cured to form elastomeric material  30 , and mold  46  may be removed (step  50 C). Step  50 C may also include shaping elastomeric material  30  and/or magnetic clusters  34  to form zipper elements  24  of a desired shape. Shaping operations may be performed using a computer-controlled cutting machine, laser cutting tools, or other suitable tools for removing portions of elastomeric material  30  and/or magnetic material  32 . In the example of  FIG. 3  portions of elastomeric material  30  are removed to expose the end portions of magnetic columns  34  and the end portions of columns  34  are shaped to form an interlocking shape (e.g., a round shape, recess, protrusion, rib, rail, cavity, key, or other suitable interlocking shape). 
       FIG. 4  is a perspective view of a portion of a magnetic closure  14  formed using the approach of  FIG. 3 . As shown in  FIG. 4 , a portion of magnetic elements  24  may be embedded within elastomeric strip  30  and another portion of magnetic elements  24  may protrude out from elastomeric strip  30  to form interlocking zipper elements. The flexibility of elastomeric material  30 ′ may allow may allow zipper  14  to form a closure on flexible materials such as fabric-based items. Because magnetic elements  24  are co-molded with elastomeric material  30 , the mechanical coupling between elements  24  and material  30  may be both robust and seamless. 
     If desired, elements  24  may have an interlocking geometry of the type shown in  FIG. 2 . In that example, individual teeth on one side of the seam alternate and interlock with individual teeth on an opposing side of the seam when zipper  14  is closed. If desired, other zipper geometries may be used.  FIGS. 5, 6, 7, and 8  show various zipper teeth geometry that may be formed using the method of  FIG. 3 . 
     In the example of  FIG. 5 , zipper element  24 A on one side of seam  50  has a protrusion  38 . Zipper element  24 B on the opposing side of seam  50  has a recess  40  that receives protrusion  38 . Because zipper elements  24 A and  24 B are magnetically attracted to one another, protrusion  38  may be guided to recess  40  by the magnetic attraction between elements  24 A and  24 B with little effort required by a user who is closing zipper  14 . 
     In the example of  FIG. 6 , elements  24 A and  24 B have a cross-sectional geometry of the type shown in  FIG. 5 . In this example, however, element  24 A is a single elongated protrusion  38  and element  24 B is a single elongated recess  40 . Elongated recess  40  may magnetically attract protrusion  38  to close zipper  14 . 
     In the example of  FIG. 7 , elements  24 A and  24 B have a cross-sectional geometry of the type shown in  FIG. 5 . In this example, however, elements  24 A are individual protrusions  38  and element  24 B is a single elongated recess  40 . Elongated recess  40  may magnetically attract individual protrusions  38  to close zipper  14 . 
     In the example of  FIG. 8 , elements  24 A and  24 B have a cross-sectional geometry of the type shown in  FIG. 5 . In this example, however, elements  24 A are individual protrusions  38  and elements  24 B are individual recesses  40 . Each individual recess  40  may magnetically attract an associated one of protrusions  38  to close zipper  14 .

Metadata:
Filing Date: 20160713
Publication Date: 20200714
Grant Date: 20200714
Priority Date: 20151023
Inventors: BHARADWAJ, SHRAVAN
Assignee: APPLE INC
CPC Classifications: [{"code": "A45C13/1069", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01F7/0263", "inventive": true, "first": false, "tree": "[]"}, {"code": "A44D2203/00", "inventive": false, "first": false, "tree": "[]"}, {"code": "A44B19/42", "inventive": true, "first": false, "tree": "[]"}, {"code": "A44B19/16", "inventive": true, "first": false, "tree": "[]"}, {"code": "A44B19/02", "inventive": true, "first": false, "tree": "[]"}, {"code": "A41F1/002", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01F13/003", "inventive": true, "first": false, "tree": "[]"}, {"code": "A41F1/002", "inventive": true, "first": false, "tree": "[]"}, {"code": "A44B19/08", "inventive": true, "first": false, "tree": "[]"}, {"code": "A44B19/42", "inventive": true, "first": true, "tree": "[]"}, {"code": "A44B19/16", "inventive": true, "first": false, "tree": "[]"}, {"code": "A44D2203/00", "inventive": false, "first": false, "tree": "[]"}, {"code": "A45C13/00", "inventive": true, "first": false, "tree": "[]"}, {"code": "A41F1/002", "inventive": true, "first": false, "tree": "[]"}, {"code": "A45C13/00", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01F13/003", "inventive": true, "first": false, "tree": "[]"}, {"code": "A44B19/16", "inventive": true, "first": false, "tree": "[]"}, {"code": "A44B19/42", "inventive": true, "first": true, "tree": "[]"}, {"code": "A44D2203/00", "inventive": false, "first": false, "tree": "[]"}, {"code": "A44B19/08", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 71519645