The slide fastener includes elements and a slider, wherein each of the elements includes a horizontal functional section an upper vertical functional section and a lower vertical functional section the slide fastener includes a plurality of fastener units in each of which the elements are arranged to oppositely face each other and the meshing portions are meshed with each other by sliding the slider between the oppositely-positioned elements, whereby the engagement pieces of the oppositely-positioned elements form an engagement portion and the engagement holding pieces of the oppositely-positioned elements in pair form an engagement holding portion, and the plurality of fastener units are constituted in a multilayered structure by engaging the engagement holding portions of a second fastener with the engagement portions of a first fastener such that the engagement holding portions of a new fastener unit are engaged with the engagement portions of a preceding fastener unit.
1. A slide fastener, comprising:
a plurality of fastener units, each of the plurality of fastener units including
fastener tapes comprising elements which are arranged in a line along oppositely-faced edges of opening/closing ends of the fastener tapes, each of the elements comprising
a horizontal section having a meshing portion on one side and a fastener-tape fixed portion on the other side, in the horizontal direction,
an upper vertical section having an engagement piece extending perpendicularly upwards from the meshing portion of the horizontal section, and
a lower vertical section having an engagement holding piece extending perpendicularly downwards from the fastener-tape fixed portion of the horizontal section, and
a slider in which the elements are arranged to oppositely face each other and in which the meshing portions of the elements are meshed with each other by sliding the slider between oppositely-faced elements, whereby the engagement pieces of the oppositely-faced elements form an engagement portion and the engagement holding pieces of the oppositely-faced elements form an engagement holding portion,
wherein the plurality of fastener units are multilayered such that the engagement holding portions of a first fastener unit among said plurality of fastener units can be engaged with the engagement portions of a second fastener unit among said plurality of fastener units, and wherein the engagement holding portions of a third fastener unit can be engaged with the engagement portions of the second fastener unit, whereby the engagement portions of the plurality of fastener units are formed in succession.
2. The slide fastener according to claim 1 ,
wherein the engagement pieces of the elements are pointed such that when the oppositely-faced elements are meshed, the engagement portion which is formed has an arrow-head shape including a pointed tip at a distal end thereof, and
wherein the engagement holding pieces of the elements have a hook shape, such that when the oppositely-faced elements are meshed, the engagement holding portion which is formed has a pyramidal shape for engagement with the engagement portion.
3. The slide fastener according to claim 1 ,
wherein the engagement pieces of the elements are pointed such that when the oppositely-faced elements are meshed, the engagement portion which is formed has an arrow-head shape including a pointed tip at a distal end thereof,
wherein the engagement pieces of the elements are shaped such that when the oppositely-faced elements are meshed, recesses are formed on an underside of the arrow-head shape,
wherein the engagement holding pieces of the elements have a hook shape including a projection, such that when the oppositely-faced elements are meshed, the engagement holding portion which is formed has a pyramidal shape for engagement with the engagement portion,
wherein the engagement holding pieces have elasticity, and
wherein the engagement portion having the arrow-head shape can be engaged with the engagement holding portion by pushing the engagement portion into the engagement holding portion, whereby the projections of the engagement holding pieces are engaged with the recesses of the engagement pieces.
4. The slide fastener according to claim 1 ,
wherein the engagement pieces of the elements each have a flat surface at a distal end thereof such that when the oppositely-faced elements are meshed, the engagement portion which is formed has a flat head shape,
wherein the engagement holding pieces of the elements have a square-channel shape, such that when the oppositely-faced elements are meshed, the engagement holding portion which is formed has a parallelpiped shape, and
wherein the engagement portion having the flat head shape is prevented from being pushed in and engaged with the engagement holding portion by an external force.