1. Field of Invention
This invention discloses an improvement applicable to laces, ropes, cables, threads, strings and similar products. The improvement specifically targeted to a task of stabilization of topological layouts of said products.
2. Prior Art
The field of invention is as old as the invention of shoe laces, and accounts numerous inventions that aid their daily use. In particular this invention relates to problem of securing fastened laces or strings. The most common approach to securely tauten laces is a knot. Stability of the knot depends on plurality of factors but mainly on lace tension and alterations in the tension, and the material of the lace. Utilization of modern highly durable synthetic materials to manufacture laces improves their tensile strength, service life, and usually reduces surface friction to assist uniform tension distribution. As a side effect it deteriorates the knot stability. Alterations in the tension of the string induce changes in diameter of string in presence of constant bias toward increase in overall length of the string. This usually results in loose knot and untied string.
Prior art inventions suggested several groups of solution for this problem. One group of inventions implies modification of the string by artificial attachments that secure ends of the string (US376041, US2869204). Second group suggests modification of shoe to secure laces from loosening (US439661, US509707). Third group suggests use of latch or clamp hardware mounted on the string to eliminate knot (US2845673, US2869204, US3074135, US3103725, US3845575 and US4967454). General flaw of these improvements is requirement of changing habits people have. These changes also include alteration of fashion or appearance, which is particularly critical for some applications such as formal wear or uniform.
This invention consists of method and improvement for any string-like object including rope, shoe lace, cord, cable, wire or alike and hereinafter referred as a lace. The lace of the invention is manufactured to produce permanent magnetic field with magnetic intensity altering across its length. Origin of the field and details of manufacturing will be disclosed in Detailed Description section.
Other inventions exist that utilize permanent magnetic field for fastening use. All of them rely on force of magnetic interaction alone to secure the position of objects or parts. One of these inventions uses magnetic edges to retain closed state of a container (US4033013). Another invention uses plastic magnets with alternating poles for the same purposes (US3468576). These inventions, although using linear patterns of magnetic fields, do not aid stabilization of knots or other topological layouts of the lace, wherein said layout carries primary tensile stress applied along the lace. Hereinafter term knot will be used to reference such layouts.
Superiority of this invention exist in absence of any external features that may visually distinguish this article from any similar traditionally manufactured laces. There is no need to alter neither user habits nor traditions. The invention provides its users assurance that knots or other tying layout will remain secure under various use scenarios. Children will be able to tie their shoes and not worry about loose laces, athletes and businessmen will be confident that their shoes are properly tauten, fastening ropes and cables will become easies to tie.
The lace structure varies depending on selection of materials and target applications. It usually includes plurality of stranded natural or synthetic polymer fibers forming outer shell of the lace. Volume inside the shell sometimes filled with additional strands of same or different material to support either shape of the lace or to provide its functional properties. For sake of clarity of disclosure only this design of the lace will be considered herein, while it is obvious that same exactly method and improvement can be embedded into the lace of any other construction.
The improvement of the invention adds additional structural component to the lace which embeds permanent magnetic field into its structure. Such embedment could be conducted through plurality of techniques. Below are some examples of some embedding techniques. These examples do not intend to limit the invention to this limited number of cases, and they are provided here for illustration purposes only.
Magnetic Patterns
The pattern of magnetic field imbedded into the lace has to satisfy the following criteria: a) the pattern must be present along segments of the lace forming the knot; b) magnetic field has to extend outside the lace diameter; c) direction and intensity must alter along the lace.
Referring to
Following examples of the lace designs may implement one of these patterns of any other pattern of magnetic field that satisfies the criteria stated above.
Organic Magnet Laces
Some or all strands composing the lace are made of organic magnetic material. Manufactured lace then magnetized using periodic magnetic pattern, wherein direction of magnetic field in such pattern can lie along the lace or perpendicular to one. As a result of magnetization the lace acquires permanent magnetic field with magnitude and or direction alternating along the lace. It is also possible to use magnetized strands during production of the lace.
Plastic Magnet Laces
Central strands of the lace are replaced or coated with film of plastic magnet, wherein in some cases said magnet can be deposited in liquid form onto surface of the lace. Said magnet is protected from mechanical wear by outer shell of polymer strands. Appearance of the lace and its mechanical properties remains the same as of the lace with no plastic magnet inside. Magnetization of the magnet executed in the same patterns as in the previous example.
Magnetic Strip Laces
Outer shell of the lace is filled with strip of flexible plastic magnet. Magnetization pattern of this lace coincides with one of the strip. The strip may be laid out in spiral or in various other patterns around central strands of the lace.
Magnetic Orbs Laces
Outer shell of the lace filled with small magnetic orbs mixed with some proportion of nonmagnetic orbs. Magnetization pattern of this lace varies during the use as orbs rearrange themselves to achieve minimal energy state. While it is possible for the orbs to rotate in magnetic field, they can not move along the lace. The proximity of different parts of the lace in the knot causes rearrangement of the orbs to lower energy state when the lace is tied up.
The same energy reduction occurs in all these examples. It caused by insignificant shift of lace segments inside the knot. This shift minimizes energy of magnetic field. Exposure of the lace to changing mechanical stresses causes further rearrangement of magnetic field of the knot toward its minimal energy state. It is customary that the knot layouts need only little friction between the lace segments to remain stable. The fiction forth depends of multiple uncontrollable conditions such as temperature, pressure, humidity, vibration, contaminations. Contrary, magnetic field energy is insensitive to all such factors. This allows the knot to remain secured during the use.
The invention provides broad spectrum of possible use. Examples below do not intend to limit the invention and provided for illustration purposes only: