BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an improved structure of metal zipper and more particularly, to a metal tooth for zipper, which enhances its engagement with the zipper tape, avoiding vibration relative to the zipper tape during operation of the metal zipper and prolonging the lifespan of the metal zipper. Further, the metal tooth has a concave surface portion formed in the protruding tooth head thereof so that less friction is produced when the metal zipper is closed or opened.
2. Description of the Related Art
In a regular metal zipper, as shown in FIG. 1, metal teeth 4 are respectively fastened to the longitudinal inner edges 31 of the respective zipper tapes 3 by a press or installation tool (not shown). According to this design, each metal tooth 4 comprises a base 40, a mounting hole 41 transversely cut through two opposite lateral sides of the base 40 for mounting. The mounting hole 41 has an outer open end 411, an inner close end 413 and a neck 412 spaced between the outer open end 411 and the inner close end 413. The base 40 has two protruding engagement portions 414 disposed at two opposite sides of the neck 412 of the mounting hole 41 (see FIG. 3) for engaging into the top and bottom sides of the longitudinal inner edges 31 of the respective zipper tape 3. This design of metal tooth 4 has drawbacks as follows:
- 1. The metal tooth 4 simply uses the two protruding engagement portions 414 of the base 40 to engage the top and bottom sides of the longitudinal inner edges 31 of the respective zipper tape 3. When the user pulls the slide 5 to close or open the metal teeth 4, the metal teeth 4 may be biased or forced out of place, causing a slide jam.
- 2. When sliding the slide 5 to close or open the metal zipper, the outer end edges 421 of the protruding tooth heads 42 of the metal teeth 4 at one zipper tape 3 may be forced to rub against the outer end edges 401′ of the bases 40′ of the metal teeth 4′ at the other zipper tape 3, producing frictional resistance. Thus, closing or opening the metal zipper become unsmooth.
SUMMARY OF THE INVENTION
The present invention has been accomplished under the circumstances in view. It is the main object of the present invention to provide a metal tooth for metal zipper, which enhances its engagement with the zipper tape, avoiding vibration relative to the zipper tape during operation of the metal zipper and prolonging the lifespan of the metal zipper.
It is another object of the present invention to provide a metal tooth for metal zipper, which reduces friction when the metal zipper is opened or closed, facilitating smooth operation of the metal zipper.
To achieve these and other objects of the present invention, a metal tooth for metal zipper has a mounting hole located on one end of the base thereof, two first engagement portions and two second engagement portions formed integral with the base at two opposite sides of the mounting hole for engaging into the top and bottom sides of the inner edge of the respective zipper tape to deform the respective inner edge during installation so that engagement between the zipper tape and the metal tooth is enhanced, avoiding vibration of the metal tooth relative to the zipper tape during operation of the metal zipper and prolonging the lifespan of the metal zipper.
Further, metal tooth has a concave surface portion formed in the protruding tooth head thereof so that less friction is produced when the metal zipper is closed or opened.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a schematic sectional view of a part of a metal zipper according to the prior art.
FIG. 2 is an enlarged view of a part of FIG. 1, illustrating the positioning of one metal tooth on the respective zipper tape.
FIG. 3 is a plain view of one metal tooth of the metal zipper according to the prior art.
FIG. 4 is a schematic sectional view illustrating a metal tooth fastened to one zipper tape according to the present invention.
FIG. 5 is a sectional view of one metal tooth for zipper according to the present invention.
FIG. 6 is an elevational view of the metal tooth shown in FIG. 5.
FIG. 7 is a schematic sectional view of a part of a metal zipper according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIGS. 4˜7, a metal zipper 2 (see FIG. 7) is shown, comprising two zipper tapes 21 each having a longitudinal inner edge 211, two series of metal teeth 1 respectively and transversely affixed to the zipper tapes 21 and spaced along the respective longitudinal inner edges 211 in a staggered manner. By means of pulling a slide (not shown) in one direction, the two series of metal teeth 1 can be interlocked, forming a chain. Each metal tooth 1 comprises a base 10, a mounting hole 11 transversely cut through one end, namely, the inner end of the base 10 on the middle (see FIG. 6), and a protruding tooth head 12 protruded from one lateral side of an opposite end, namely, the outer end of the base 10. The mounting hole 11 has an outer open end 111, an inner close end 115, a first neck 112 spaced between the outer open end 111 and the inner close end 115, a second neck 114 spaced between the first neck 112 and the inner close end 115, and a flank portion 113 defined between the first neck 112 and the second neck 114. The base 10 has two opposing first engagement portions 116 respectively disposed at two opposite sides of the first neck 112, and two opposing second engagement portions 117 respectively disposed at two opposite sides of the second neck 114. By means of the first engagement portions 116 and second engagement portions 117, the base 10 of each metal tooth 1 is affixed to the longitudinal inner edge 211 of one respective zipper tape 21. During installation, the first engagement portions 116 and second engagement portions 117 of the base 10 of each metal tooth 1 are respectively engaged into the top and bottom sides of the inner edge 211 of the respective zipper tape 21 to deform the respective inner edge 211, enhancing engagement between the zipper tape 21 and the metal tooth 1, avoiding vibration of the metal tooth 1 relative to the zipper tape 21 and prolonging the lifespan of the metal zipper.
Each metal tooth 1 further comprises a notch 13 located on the other lateral side of the outer end of the base 10 opposite to the protruding tooth head 12. Further, the protruding tooth head 12 has a bevel face 121 located on one side thereof adjacent to the mounting hole 11, a slope face 122 located on an opposite side thereof remote from the mounting hole 11 and a concave surface portion 1221 formed in the slope face 122. Further, the slope face 122 may be smoothly arched. Subject to the effect of the concave surface portion 1221, less friction or resistance is produced when closing or opening the two series of metal teeth 1, i.e., when closing or opening the metal zipper 2, the concave surface portions 1221 of the metal teeth 1 at one zipper tape 21 provide a respective space for receiving the outer end edges 131 of the metal teeth 1 at the other zipper tape 21 (see FIG. 7), avoiding friction between the two series of metal teeth 1 and facilitating metal zipper closing or opening operation.
When compared to the prior art design, the mounting hole 11 of the base 10 of each metal tooth 1 of the present invention has an outer open end 111, an inner close end 115, a first neck 112 spaced between the outer open end 111 and the inner close end 115, a second neck 114 spaced between the first neck 112 and the inner close end 115 and a flank portion 113 defined between the first neck 112 and the second neck 114, and the base 10 of each metal tooth 1 of the present invention has two opposing first engagement portions 116 respectively disposed at two opposite sides of the first neck 112, and two opposing second engagement portions 117 respectively disposed at two opposite sides of the second neck 114. During installation, the first engagement portions 116 and second engagement portions 117 of the base 10 of each metal tooth 1 are respectively engaged into the top and bottom sides of the inner edge 211 of the respective zipper tape 21 to deform the respective inner edge 211, enhancing engagement between the zipper tape 21 and the metal tooth 1, avoiding vibration of the metal tooth 1 relative to the zipper tape 21 and prolonging the lifespan of the metal zipper. Further, the protruding tooth head 12 has a bevel face 121 located on one side thereof adjacent to the mounting hole 11, a slope face 122 located on an opposite side thereof remote from the mounting hole 11 and a concave surface portion 1221 formed in the slope face 122. Subject to the effect of the concave surface portion 1221, less friction or resistance is produced when closing or opening the two series of metal teeth 1,
In general, the invention has the following benefits:
- 1. By means of the first engagement portions 116 and second engagement portions 117, the base 10 of each metal tooth 1 is affixed to the longitudinal inner edge 211 of one respective zipper tape 21. During installation, the first engagement portions 116 and second engagement portions 117 of the base 10 of each metal tooth 1 are respectively engaged into the top and bottom sides of the inner edge 211 of the respective zipper tape 21 to deform the respective inner edge 211, enhancing engagement between the zipper tape 21 and the metal tooth 1, avoiding vibration of the metal tooth 1 relative to the zipper tape 21 and prolonging the lifespan of the metal zipper.
- 2. When closing or opening the metal zipper 2, the concave surface portions 1221 of the metal teeth 1 at one zipper tape 21 provide a respective space for receiving the outer end edges 131 of the metal teeth 1 at the other zipper tape 21 (see FIG. 7), avoiding friction between the two series of metal teeth 1 and facilitating metal zipper closing or opening operation.
While only one embodiment of the present invention has been shown and described, it will be understood that various modifications and changes could be made thereunto without departing from the spirit and scope of the invention disclosed.
Patent Application
20120036685
