GB2305109A - A jewellery/earring fastener with spiral stem and non-threaded backfitting - Google Patents

Abstract

A jewellery item such as an earring, includes a decorative portion 3 and a fastener comprising a stem 1 and a backfitting 2, one end of the stem being secured to the decorative portion 3. The stem is of rectangular cross-section which is twisted about its axis to provide a spiral path, and the heart-shaped backfitting has in a base 5 thereof an opening 8 of rectangular section and of a size to fit closely over the rectangular section free end portion of the stem, to allow the backfitting to be screwed onto the twisted, spiral path so that it moves therealong to retain the earring in position in use. Opposite arm portions 6A, 7A of the backfitting engage the stem and provide sufficient frictional resistance to prevent/resist unintentional releasing rotation of the backfitting along the stem. The backfitting is produced from a blank (2A, Fig. 6) in which the opening 8 is formed prior to the blank being folded into the heart shape of the backfitting or alternatively formed in the finally shaped backfitting.

Description

JEWELLERY FASTENER This invention relates to a jewellery fastener which includes a stem, such as a pin or post, intended to pass through a pierced body part of a wearer, such as an ear or nostril lobe, and to carry a decorative portion for display on the body part, and a backfitting intended for mounting on the stem to retain the fastener in position, in use, on the body part. The invention will also be understood to embrace a jewellery item comprising the aforesaid fastener together with the decorative portion mounted on the stem.

In known jewellery items of this kind, the stem is passed through the pierced body part to bring the decorative portion to a desired display position on a surface of the body part, the backfitting, commonly in the form of a scroll or other securing device, being engaged with the stem to lie against an opposite surface of the body part and usually engaging a formation, such as a circumferential groove in the pin or post, in order to retain the jewellery item in place on the body part. Whilst this kind of arrangement can be satisfactory over a period of use, the grip of the backfitting can gradually weaken, with the consequent risk of loss of the jewellery item from the body part.

An object of the invention is to provide an improved fastener for a jewellery item, and a jewellery item incorporating such a fastener.

According to one aspect of the invention, the stem of the fastener defines a spiral path along at least a part of its length, and the backfitting has an opening therethrough which is internally non-threaded, and which is configured so that the backfitting can only travel along the spiral path of the stem as a result of relative rotational movement between the stem and the backfitting.

Preferably, the spiral path is formed by twisting an externally plain stem blank, conveniently of generally rectangular transverse cross-section.

Typically, the opening in the backfitting is an elongate slot, conveniently of generally rectangular form corresponding to that of the stem blank cross-section.

According to a another aspect of the invention, there is provided a method of manufacturing a jewellery fastener comprising producing a spiral formation along at least a part of the length of a stem, and forming in a backfitting, or in a blank for producing the backfitting, an opening which is internally non-threaded and which is configured so that the backfitting, when assembled on the stem, can only travel along the spiral formation of the stem as a result of relative rotational movement between the stem and the backfitting.

The invention will now be described, by way of example, with reference to the accompanying drawings in which: Figure 1 is an exploded side view of one embodiment of a jewellery item according to the invention; Figure 2 illustrates the jewellery item of Figure 1 in assembled condition; Figure 3 is a rear view of one component of the jewellery item of Figure 1; Figure 4 is a front end view of the other component of the jewellery item of Figure 1; Figure 5 is a front view of the assembled jewellery item of Figure 2, and Figure 6 illustrates a blank from which the component of Figure 3 is produced.

Figures 1 to 4 of the drawings illustrate a jewellery item, in the form of an earring, incorporating a fastener of the invention. The fastener is composed of a stem 1 and a backfitting 2 which is intended to be carried by the stem 1 in order to retain the earring in place, in use, in the manner to be described. The earring is completed by a decorative part 3, which, in this example, is cylindrical, and has on its rear face a housing in the form of a socket 4 into which one end portion of the stem 1 is securely fixed, as for example by soldering. Instead the stem could merely be secured into a hole in the part 3.

The stem itself is formed from elongate material, such as circular-section wire, which is rolled flat into thin strip material having an externally plain, generally rectangular cross-section, and then provided with a spiral formation by twisting part, or as shown, all, of the length of the strip about its own longitudinal axis. The backfitting is also formed from relatively thin gauge strip and is generally "heart-shaped" having an inwardly curved base 5, from the extremities of which extend curvate arms 6, 7 of which the respective end portions 6A, 7A are outwardly turned. When the backfitting is not engaged on the stem, the arm portions 6A, 7A lie either in a contiguous relationship, or spaced apart by less than the maximum diametric dimension of the stem.The base 5 of the backfitting is provided with a plain, non-threaded, elongated slot, in the form of a through-opening 8 which, as can be seen more clearly from Figure 3, is, in this example, of rectangular section and of such a size as to fit closely over the rectangular section free end portion 1A of the stem 1 (Figure 4).

As can be seen more clearly from Figure 6, the backfitting is formed from a generally elliptical blank 2A of thin gauge sheet material having the rectangular opening 8 stamped or otherwise formed therein, the blank thereafter being folded, using a suitable press, to its final shape.

Alternatively the opening 8 could be formed in the finally shaped backfitting, instead of in the blank.

In order to fit the jewellery item for display on a pierced ear lobe, the stem 1 is passed through the ear lobe until the decorative part 3 lies against an outwardly facing surface of the lobe. The backfitting is then offered to the rectangular section free end 1A of the stem which is engaged in the slot 8, following which the backfitting is rotated in a suitable direction, usually clockwise, to cause the backfitting to ride along the stem spiral, guided by the portions 6A, 7A, to a position in which it exerts a desired comfortable pressure on the opposed face of the lobe. During this process, the arms, 6, 7 engage the outer surface of the stem and, with the backfitting in its desired position, provide sufficient frictional resistance to unintentional rotation of the backfitting on the stem to prevent/resist unwinding/untwisting of the backfitting along the stem.

It will be understood that the strip from which the stem 1 is formed may have a cross-section different from the rectangular one described and illustrated, possible alternative examples being square or triangular. The shape of the opening 8 can correspondingly be different from that shown. Whilst it is extremely cost effective and convenient to produce the stem spiral by twisting in the manner described, it would be possible to produce a suitable formation by the removal of material from a plain solid stem, using conventional machining techniques. The backfitting may take a variety of alternative forms but would preferably have at least one portion bearing upon the stem, in use, to provide the desired resistance to unwinding/untwisting.

Claims (24)

1. A jewellery fastener comprising a stem, intended to pass, in use, through a pierced body part of a wearer, and a backfitting intended for mounting on the stem to retain the fastener in position, in use, on the body part, the stem defining a spiral path along at least part of its length, and the backfitting having an opening therethrough which is internally non-threaded, and which is configurated so that the backfitting can only travel along the spiral path of the stem as a result of relative rotational movement between the stem and the backfitting.

2. A jewellery fastener as claimed in Claim 1, wherein the backfitting has a base part in which said opening is provided and at least one arm part arranged to engage said spiral path of the stem, in use, when the backfitting is mounted thereon, to resist untwisting of the backfitti ng.

3. A jewellery fastener as claimed in Claim 2, wherein the backfitting has two of said arm parts extending from respective opposite ends of said base part, to engage respective opposite sides of said stem, in use.

4. A jewellery fastener as claimed in any one of Claims 1 to 3, wherein the backfitting is generally heart-shaped.

5. A jewellery fastener as claimed in any one of the preceding claims, wherein the spiral path is a twisted length of an externally plain stem blank.

6. A jewellery fastener as claimed in Claim 5, wherein the stem blank is of generally rectangular cross-section.

7. A jewellery fastener as claimed in Claim 5 or Claim 6, wherein the opening in the backfitting is an elongated slot.

8. A jewellery fastener as claimed in Claim 7, wherein the slot is of generally rectangular form corresponding to that of the stem blank.

9. A jewellery item incorporating a fastener as claimed in any one of the preceding claims, wherein an end of the stem is fixed to a decorative portion for display on said body part.

10. A jewellery item as claimed in Claim 9, wherein the decorative portion has a socket into which the stem end is secured.

11. A jewellery item as claimed in Claim 9 or Claim 10, wherein the end of the stem is fixed to the decorative portion by soldering.

12. A jewellery item as claimed in any one of Claims 9 to 11, wherein the decorative portion is an earring.

13. A method of manufacturing a jewellery fastener comprising producing a spiral formation along at least a part of the length of a stem, and forming in a backfitting, or in a blank for producing the backfitting, an opening which is internally non-threaded and which is configured so that the backfitting, when assembled on the stem, can only travel along the spiral formation of the stem as a result of relative rotational movement between the stem and the backfitting.

14. A method as claimed in Claim 13, comprising twisting an externally plain stem blank about its longitudinal axis to produce said spiral formation.

15. A method as claimed in Claim 14, comprising rolling circularsection wire to form said plain stem blank.

16. A method as claimed in any one of Claims 13 to 15, comprising forming said opening in said blank for producing the backfitting and then folding the blank into the desired backfitting shape.

17. A method as claimed in Claim 16, comprising folding the blank for the backfitting into a heart-shaped form with respective opposite end parts of arms thereof being arranged so that they engage respective opposite sides of said spiral formation, in use, when the backfitting is assembled thereon.

18. A method of manufacturing a jewellery item incorporating manufacturing a jewellery fastener as claimed in any one of Claims 1 3 to 17, comprising fixing an end of said stem to a decorative portion for displaying on said body part.

19. A method as claimed in Claim 18, comprising fixing said stem end into a socket provided by said decorative portion.

20. A method as claimed in Claim 19, comprising fixing said stem end into said socket by soldering.

21. A jewellery fastener substantially as hereinbefore described, with reference to, and as shown in Figures 1 to 5 of the accompanying drawings.

22. A jewellery item substantially as hereinbefore described, with reference to, and as shown in Figures 1, 2 and 5 of the accompanying drawings.

23. A method of manufacturing a jewellery fastener substantially as hereinbefore described, with reference to, and as shown in Figure 6 of the accompanying drawings.

24. A method of manufacturing a jewellery item substantially as hereinbefore described, with reference to, and as shown in Figure 6 of the accompanying drawings.