GB2030212A - Zip fastener slider - Google Patents

Abstract

A zip has a slider comprising upper and lower separate elements (1 and 2) detachably connected together by a pillar having two portions (5 and 6), one connected to each of the elements (1 and 2). A screw (9) extends through the pillar portions to effect the connection. Such a slider is easily replaceable upon failure thereof. <IMAGE>

Description

SPECIFICATION Zips The present invention relates to zip fasteners.

Zip fasteners comprise two strips or tapes of material along the edge of each of which is provided a row of teeth. The tapes may be arranged with the rows of teeth adjacent and each tooth of one row engaged between two adjacent teeth of the other row to secure the two tapes together. A slider is provided which defines an open-sided passageway through which the two rows of teeth pass, move ment ofthe slider in one direction along the rows forcing the teeth into mutual engagement and movement of the slider in the other direction pulling the engaged teeth apart.

The slider comprises upper and lower members with flanged edges defining the passageway through which the two rows of teeth pass. The passageway tapers from one end to the other, and a pillar linking the upper and lower members is located at the under end of the passageway. The separated rows of teeth extend into the passageway on respective sides of the pillar and emerge in engagement with each other at the narrower end of the passageway. Thus, by moving the slider pillar end first along the rows, the teeth are forced into mutual engagement in the narrower end of the passageway, and by moving the slider in the oppo site direction, the teeth are forced apart by the pillar.

The forces acting on the slider during use are considerable and the slider is generally cast to provide the necessary rigidity. The high forces exerted on the slider does however result in rapid wear, particularly in the case of heavy duty zips as used for example in tents. Once the slider becomes worn, the forces required to operate it increase, thereby increasing the stress. Eventually the slider fails either as a result of excessive wear allowing the teeth to pull out of the slider or as a result of breakage of the pillar which can occur when attempts are made to operate a worn slider.

Once the slider fails it is necessary to replace the entire zip even though the teeth are in good condition as new sliders are not available and if they were could not be fitted onto the teeth. The cost of a new zip is considerable, but of more significance is the cost involved in replacing the old zip tapes as this requires machining.

It is an object of the present invention to provide a slider for a zip which is easily replaceable.

According to the present invention there is provided a sliderfora zip comprising a body defining a passageway for receiving two rows of zip teeth, the passageway being shaped to enable movement of the slider in one direction to interengage the two rows of teeth and movement in the other direction to force the interengaged teeth apart, characterised in that the body comprises at least two separable elements, the elements when separated providing access to the passageway such that the rows of teeth can be inserted into the passageway and the ele ments subsequently assembled to secure the slider on the rows of teeth.

Preferably the slider comprises separable upper and lower members united by a piller. The pillar may be hollow and comprise two elements one integral with each of the upper and lower members. A screw may be inserted through the hollow pillar to secure the upper and lower members together. The mating faces of the two elements of the pillar maybe irregular to resist relative rotation between the upper and lower members.

An embodiment of the present invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a perspective view of a zip slider according to the invention; Figure2 is a section on the line II - II of Figure 1; and Figure 3 shows the operative relationship between the slider of Figures 1 and 2 and rows of zip teeth on which the slider is mounted.

Referring to Figure 1, the illustrated slider comprises upper element 1, lower element 2, and upper and lower operating tabs 3, 4. A hollow pillar unites the upper and lower elements, a first portion 5 of the pillar being integral with the upper element. 1 and a second portion 6 being integral with the lower element 2. The portions 5 and 6 mate along line 7.

The side edges are provided with inwardly extending flanges 8.

A screw 9 extends through the hollow pillar and engages in a thread (not shown) integral with the lower element 2. The mating faces of the pillar are stepped such that rotation of one element relative to the other is resisted.

Referring to Figures 2 and 3, the flanges 8 define an open-sided passageway 10 which tapers from the end adjacent the pillar to a parallel sided lower section. Two rows of teeth 11 mounted on tapes 12, 13 pass on either side of the pillar. If the slider is moved upwards in Figure 3, the teeth are pushed together beneath the pillar by the action of the flanges 8 and emerge from the slider in their mutually engaged state. If the slider is moved downwards in Figure 3, a tapered edge 14 of the pillar is forced between the teeth and the teeth 11 are forced apart.

The normal operation of the slider is conventional.

If however the slider is rendered inoperative as the result for example of becoming worn that the flanges 8 are no longer capable of forcing the teeth together correctly, rather than having to discard the entire zip including teeth 11 and tapes 12, 13, the slider can be removed by unfastening screw 9 and pulling the upper and lower elements 1,2 apart. A new slider can then be assembled with the teeth inside the passageway 10 without difficulty.

The screw 9 may be pivotally connected to the tab 3 so that it can be tightened by rotating the tab 3 rather than requiring the use of a screwdriver.

It will be appreciated that alternative embodiments to that described may be provided. For example, the cross-sectional area of the pillar may be substantially increased by extending the pillar on the side thereof remote from the passageway 10.

Claims (8)

1. A slider for a zip comprising a body defining a passageway for receiving two rows of zip teeth, the passageway being shaped to enable movement of the slider in one direction to interengage the two rows of teeth and movement in the other direction to force the interengaged teeth apart, characterised in that the body comprises at least two separable elements, the elements when separated providing access to the passageway such that the rows of teeth can be inserted into the passageway and the elements subsequently assembled to secure the slider on the rows of teeth.

2. A slider as claimed in claim 1 in which the body comprises upper and lower elements united by a pillar.

3. A slider as claimed in claim 2, in which the pillar is hollow and comprises two portions, one integral with each of the upper and lower elements.

4. A slider as claimed in claim 3, comprising a screw inserted through the hollow pillar to secure the upper and lower elements together.

5. A slider as claimed in claim 3, in which mating faces of the two pillar portions are irregular to resist relative rotation between the upper and lower elements.

6. Aslider as claimed in claim 4, comprising a tab pivotally cdnnected to the screw whereby the latter can be tightened by rotating the tab.

7. A slider for a zip substantially as hereinbefore described with reference to the accompanying drawings.

8. Azip incorporating a slider as claimed in any one of the preceding claims.