WO2003005847A1

WO2003005847A1 - Magnetic strap fastener

Info

Publication number: WO2003005847A1
Application number: PCT/IB2002/002695
Authority: WO
Inventors: Sheung Chung Wong
Original assignee: Davies, Paul, R.
Priority date: 2001-07-09
Filing date: 2002-07-09
Publication date: 2003-01-23
Also published as: CN1555234A; HK1045780A2; EP1408786A1; JP2004533896A; ES2301661T3; HK1067019A1; KR20040030040A; KR100732730B1; ATE385710T1; EP1408786B1; CN1282432C; DE60225012D1; JP4567331B2

Abstract

Magnetic fastener pairs with low-profile designs which allow strong magnetic coupling between the constituting magnetic fastening members while also permitting easy intentional separation. Each of the magnetic fasteners includes a magnet receptacle and a permanent magnet made preferably of a strong magnetic alloy. Each magnet member is backed by a ferro-magnetic base of the magnet receptacle of the fastener member and with an exposed coupling surface for strong magnetic coupling while allowing easy intentional separation.

Description

MAGNETIC STRAP FASTENER

FIELD OF THE INVENTION

The present invention relates generally to fasteners and, more particularly, to magnetic fasteners such as magnetic clasps, buckles and magnetic strap or belt fasteners. More specifically, although of course not solely limiting thereto, the present invention relates to fasteners such as clasps or buckles for use in or with apparel such as a brassiere or the like. This invention also relates to apparel with magnetic fasteners.

BACKGROUND OF THE INVENTION

Unlike conventional fastener assemblies such as an array of buttons in which a button is fastened and released by inserting it into or removing it from a button hole, magnetic buttons and fasteners are fastened or secured by mutual

magnetic attraction between a complementary pair of magnetic fasteners or buttons having complementary or opposite magnetic properties. This unique property of magnetic fasteners means that they can be automatically fastened when a detachable pair is in the proximity of each other. At the same time, coupled magnetic buttons can be separated simply by pulling the fasteners or buttons apart and move them away from each other. Also, unlike conventional fasteners such as button assemblies which have to be fastened and released sequentially, an array of magnetic buttons can be simultaneously fastened or released. The above distinctive characteristics find magnetic fasteners particularly useful in circumstances in which the fasteners are required to be done and undone with a single hand and within a short time. For example, magnetic fasteners are useful in costumes for artists or performers who need to change frequently on stage. They are also useful for workers who wear work clothes and vests which may be caught by machinery or moving objects. Clothes or work vests with magnetic buttons provide easy escape to save the wearer from being caught and hurt when the clothes or vests are engaged accidentally.

As mentioned above, typical magnetic buttons include a pair of complementary parts which are releasably attachable to each other by magnetic attraction. Each of the detachable parts usually includes a magnetic member in slab or tablet form having a top and a bottom magnetic coupling surfaces with the opposite magnetic poles formed on them. The magnetic coupling surfaces are usually interconnected by a continuous peripheral edge which is usually quite thin for aesthetic and styling consideration. The magnetic slabs or tablets are usually

cylindrical in shape with substantially identical top and bottom surfaces.

The magnetic slabs or tablets are generally enclosed in a magnetic permeable housing which are made, for example, of rubber, Nylon, fabrics, plastics (such as ABS or PVC) or synthetic resin. The housing makes decoration to the magnetic fasteners possible by providing a cover of aesthetic design to the magnetic member which usually has a monotonous and dull metallic appearance as well as providing weathering shield to the magnetic material to slow down or retard undesirable rusting. In this regard, the enclosure is preferably water- or airtight so that even if the magnet member is oxidized, the enclosure still provides a cosmetic cover to hide the rusted surfaces from the outside, thereby making magnetic buttons suitable for applications in which product presentation and

appearance are important.

To further enhance the convenience and usefulness of magnetic fasteners, magnetic fasteners are always made with complementary magnetic members having identical shapes and dimensions. As a result of the substantially identical dimensions of the complementary magnetic coupling surfaces on the detachable parts, the parts will come into substantially automatic alignment once they come into contact and no external help is therefore required in general for the initial contact and the subsequent engagement.

In view of the many advantages offered by magnetic clasps or buckles, it

will be expected that magnetic belt or strap fasteners such as strap clasps and buckles should be much more widely used, for example and especially, in applications where the buckles are hard to reach or locate or in applications where the buckles are normally concealed underneath other surfaces during use. One example of such applications is in lingeries or brassieres where the clasps or buckles are usually located at the back or at locations which are not conveniently accessible. Another example is for braces in which some of the fasteners are to be fastened to the back of trousers. In these applications, the appearance of the fasteners is usually important as their selection is sometimes considered to be representative or reflective of the taste of the user.

Hitherto, magnetic clasps or buckles are not as widely used as expected in such applications. Main reasons for this are probably because conventional magnetic clasps and buckles are generally complex, expensive, heavy, un-sightly, of a bulky build and sometimes difficult to use.

Conventional magnetic fasteners are generally difficult to use because they are usually provided with additional engagement means to prevent accidental disengagement of the magnetic pairs since magnetic fasteners of conventional designs are generally not magnetically strong enough to reliably hold the magnetic pairs together. Such additional engagement means also cause difficulty when intentional disenegagement is desired. Furthermore, since magnetic buttons are characterised by engagement by mutual magnetic attraction of the coupling surfaces having opposite or complementary magnetic polarities and since magnetic coupling forces are usually strongest in the direction which is substantially normal or perpendicular to the coupling surfaces, the mutual lateral attraction is relatively weak and lateral dislocation of the buttons may occur relatively easily by lateral pulling of the buttons which may cause inadvertent or accidental disengagement of the fasteners when a lateral tension is applied. While it may be possible to retard undesirable lateral movement by providing matted or frictional coupling surfaces, this would usually decrease the ease of self alignment between the coupling surfaces and are therefore is not an attractive option. Hence, the conflicting requirements, namely, that the fasteners should be easy to separate when desired and securely fastened together otherwise, have to be met if magnetic fasteners are to be widely used.

For example, European Patent Application No.EP923887 discloses a magnetic closure with mutual interlock for bags, knapsacks and items of clothing. This device combines a magnetic closure with a snap-acting closure that contains a pair of male and female parts, h the preferred embodiment, the male element forms a projection that contains a catch for insertion into a slot of the female element for interlocking purposes to prevent natural slippage. Pressing action of the male element allows a user to unlock and separate the two parts. Such a design would effectively require two actions for unlocking of the closure: the pulling apart of the magnet, and the opening of the male and female elements.

Hence, it will be desirable if magnetic buckles having at least some of the afore-mentioned shortcomings overcome or alleviated can be provided so that light, reliable and simple strap fasteners can be provided. Preferably such strap fasteners should have a low-profile structure which allows decoration to be conveniently and easily added to the buckles to make them more aesthetically pleasing - an important aspect if magnetic buckles are to be widely used in lingerie, fashions or apparel, hi addition, a low-profile structure usually alleviates the risks of damages to the covering or adjacent soft materials. However, conventional low- profile designs usually mean insufficient magnetic binding force between the magnetic pairs and complicated and additional engagement means are hitherto inevitable for such low-profile designs. Naturally, it is highly desirable if such fasteners can be snap-fitted and easily disengageable as and when desired by the user.

Throughout this specification, the terms fasteners, buckles and buttons are used interchangeably for brevity and succinctness to the extent that is appropriate for the context.

OBJECT OF THE INVENTION

It is therefore an object of the present invention to provide a magnetic strap fastener or buckle which is light, of a simple structure and inexpensive, hi addition, the strap fastener or buckle should have a low-profile build so that it can be easily and conveniently concealed under clothes or other surfaces for aesthetic consideration so that such fasteners can be generally used in the manufacture of under-clothings such as brassieres and lingeries. Preferably, no additional complicated engagement means are required by the fasteners to safeguard from

accidental and adverse disengagement, h this regard, the design of magnetic fasteners which provide strong magnetic binding between the pairs while at the same time allowing relatively easy disengagement when desired is also an object of the present invention.

Preferably, in addition to the afore-mentioned requirements, the buckles should be reasonably reliable so that the risks of accidental disengagement of the buckles or strap fasteners are minimal. As a minimum, it is the object of the present invention to provide the public with a choice of a new form of magnetic fasteners as described herein.

SUMMARY OF THE INVENTION

According to one aspect of the present invention, there is provided a magnetic buckle or strap fastener including a housing and a magnetic member, said magnetic member includes a first surface of a first magnetic polarity and a second surface of a second and opposite magnetic polarity, the perimeters of said first and said second surfaces are joined by a thin peripheral wall, said housing includes a holder for receiving said magnetic member so that at least one surface of said magnetic member will substantially expose and a strap receiving means extending away from said peripheral wall in a direction which is substantially perpendicular to said peripheral wall

According to another aspect, the present invention provides a fastener including a housing and a magnetic member. The magnetic member includes a first surface and an opposing second surface corresponding to a first magnetic pole and a second magnetic pole respectively, with the first and second magnetic poles defining a magnetic axis therebetween. The housing contains a receptacle for receiving the magnetic member, a strap receiving means extending from the receptacle, and a stopping mechanism for preventing lateral slippage when the fastener is functionally engaged with another matching fastener. The stopping mechanism is preferably provided in the housing and adapted to engage the matching fastener containing a matching housing and a matching magnetic member. The stopping mechanism is designed in the housing such that it is capable of being disengaged in a single action to pull the fastener and matching fastener apart along a direction substantially parallel to the magnetic axis.

Preferably, the holder includes a base portion and a wall extending upwardly from the perimeter of said base portion, said base portion is adjacent one surface of said magnetic member and said wall is adapted to surround the

peripheral wall of said magnetic member.

Preferably the wall discontinues at about the junction between said strap receiving means and said base portion.

Preferably, the holder includes a wall surrounding the peripheral wall of said magnetic member, said wall includes an elevated portion protruding beyond the exposed magnetic surface.

Preferably, the elevated portion is adapted so that when said strap fastener is magnetically coupled with a counter-part strap fastener of the same design, said elevated portion will not push against the strap receiving means of the counter-part fastener while forming a barrier member to stop relative lateral movement along the directions of the strap receiving means.

According to a further aspect of the present invention, there is provided a strap fastener or a buckle including a housing and a magnetic member, said magnetic member includes a first and a second magnetic polar surfaces respectively of a first and a second magnetic polarities which together define a magnetic axis, said housing includes a receptacle for receiving said magnetic member and a strap receiving means, said strap receiving means is formed on said receptacle and is transverse to said magnetic axis.

Preferably, the strap fastener further including a projection which is disposed on the edge of said receptacle at a position which is substantially opposite to said strap receiving means and which extends beyond the magnetic polar surface which is adapted for coupling with a counterpart magnetic coupling surface.

According to yet another aspect of the present invention, there is provided a

buckle or strap fastener comprising a pair of engageable magnetic fasteners of opposite polarity to each other engageable or a common axis and a strap engagement portion connected to each magnetic fastener and extending transverse to said common axis of engagement of said magnetic fasteners. Preferably, said fastener includes at least one protrusion to reside against a perimeter of an opposed magnetic fastener to resist lateral movement of one magnetic fastener with respect to the other and transverse to said common axis on which they engage.

According to yet another further aspect of the present invention, there are provided apparel such as lingerie, braces and vests with magnetic fasteners

described above and in the detailed description below.

According to yet another aspect of the present invention, there is provided a strap fastener including a housing and a magnetic member, said magnetic member includes a first magnetic coupling surface of a first magnetic polarity and a second magnetic surface of a second and opposite magnetic polarity, the perimeters of said first and said second magnetic surfaces are joined by a peripheral wall, said housing includes a magnetic member holder for receiving said magnetic member, said magnetic member holder includes a base portion on which said second magnetic surface of said magnetic member is received, said base portion includes a surface of ferro-magnetic material which substantially contact said second magnetic surface of said magnetic member, said magnetic member holder further includes an upstanding wall extending from said base portion, said upstanding wall surrounds at least a portion of said peripheral wall of said magnetic member, said magnetic member being received on said magnetic member holder such that said first magnetic coupling surface of said magnetic member is substantially exposed, said housing further includes a strap receiving means which generally extends away from said peripheral wall of said magnetic member in a direction which is substantially perpendicular to said peripheral wall of said magnetic member.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the present invention will now be explained by way of examples and with reference to the accompanying drawings in which:-

Fig. 1 illustrates the cross-sectional of a magnetic member and a housing to be described in the first embodiment of the present invention

Fig. 2 shows the top plan view of the housing of Fig.1. Fig. 3 is a diagram showing generally the housing and indicating a

protruding portion extending from the peripheral wall of the holder to alleviate

undesirable relative lateral slippage of a buckle pair, and

Fig. 4 is a cross sectional view illustrating a pair of the buckles engaged

together.

Fig. 4A is a perspective view showing the fastening members separated.

Fig. 5A is an exploded cross sectional view of a pair of fasteners according

to another or second embodiment of the present invention.

Fig. 5B is a cross sectional view of a fastener according to the embodiment

of Fig. 5 A of the present invention.

Fig. 5C is a top plan view of the same fastener as in Fig. 5B.

Fig. 5D is a cross sectional side view of a pair of fasteners functionally

engaged according to the same embodiment of the present invention.

Fig. 5E is a top plan view of the same pair of fasteners according to Fig.

5D.

Fig. 6A is an exploded cross sectional side view of a fastener according to

yet another or third embodiment of the present invention.

Fig. 6B is the cross sectional side view of the same fastener as in Fig. 6 A.

Fig. 6C is the top plan view of the same fastener as Fig. 6A. Fig. 6D is the cross sectional side view of a pair of fasteners functionally

engaged according to the same embodiment as in Fig. 6A.

Fig. 6E is a top plan view of the same pair of fasteners as in Fig. 6D.

Fig. 7A is an exploded cross sectional side view of a magnet set according

to a further or fourth embodiment of the present invention.

Fig. 7B is the cross sectional side view of the same magnet set as in Fig.

7A.

Fig. 7C is the top view of the same magnet set as shown in Fig. 7 A.

Fig. 8A is the top plan view of a pair of magnetic fasteners according to a

fifth embodiment of the present invention.

Fig. 8B is an exploded cross-sectional view of a first part of the magnetic

fasteners of Fig. 8 A.

Fig. 8C is an exploded and cross-sectional view of a second,

complementary, part of the magnetic fastener of Fig. 8 A.

Fig. 8D is a cross-sectional view taken along the horizontal middle line of

Fig. 8 A showing the two complementary parts fastened together.

Fig. 9A is a top plan view of a sixth embodiment of a pair of magnetic

fasteners according to a sixth embodiment of the present invention. Fig. 9B is a cross-sectional view showing an exploded view of a

constituting magnetic fastener of the fasteners of Fig. 9 A.

Fig. 9C is a cross-sectional view showing the magnetic fasteners of Fig. 9A

where assembled.

Fig. 10A is a top plan view of a seventh embodiment of a pair of magnetic

fasteners according to a sixth embodiment of the present invention.

Fig. 10B is a cross-sectional view showing an exploded view of a

constituting magnetic fastener of the fasteners of Fig. 10A.

Fig. IOC is a cross-sectional view showing the magnetic fasteners of Fig.

10A where assembled.

Fig. 11A is the top plan view of a pair of magnetic fasteners according to a

seventh embodiment of the present invention.

Fig. 1 IB is an exploded cross-sectional view of a first part of the magnetic

fasteners of Fig. 11 A.

Fig. 11C is an exploded and cross-sectional view of a second,

complementary, part of the magnetic fastener of Fig. 11A.

Fig. 1 ID is a cross-sectional view taken along the horizontal middle line of

Fig. 11 A showing the two complementary parts fastened together.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring firstly to Figs. 1 to 3, there are shown a magnetic member (10) and a housing (20) which, when assembled together, form a first preferred embodiment of the present invention of a magnetic buckle. The magnetic member (10) is the source of the magnetic coupling force for engaging with a counterpart magnetic buckle. Preferably, this magnetic member includes a permanent magnet in the form of a magnetic slab made of a strong magnetic substance or alloy in order to provide a large magnetic force-to-volume ratio essential for a compact buckle design. With the current magnetic technology, a pair of complementary magnetic slabs having a diameter of 1cm and a thickness of about 1mm and with an appropriate design as mentioned herein can produce a magnetic coupling force of up to 20-30 N.

In the present preferred example, the magnetic slab is substantially circular or cylindrical with a diameter of about 12mm and a thickness of less than 1mm. To provide a maximum magnetic coupling area, the two opposite magnetic poles are preferably disposed on the two opposing planes (11, 12) of the magnetic slab so that the North pole is on one of the planar surfaces while the South pole is on the other with a perimeter wall (12A) therebetween. To increase the magnetic flux intensity on the coupling surface, the magnet member is preferable embedded within a casing made of a magnetic material, such as an iron, steel or other ferro- magnetic casing, with one of the magnetic coupling surface exposed. With such an embedment of a strong magnet on a ferro-magnetic casing, the magnetic strength of the exposed coupling surface is considerably strengthened by concentration. Of course, magnetic members of other shapes and thickness can equally be used without loss of generality. For example, the magnetic member can be made into a rectangular, polygonal, trapezoidal or even irregular or non-geometric cross- section. In addition, a ring- or toroidal shaped magnetic member can also be utilized.

The housing includes a holder portion (21) or receptacle for receiving the magnetic member and a strap receiving portion (25) for anchoring a flexible end of a strap for releasable engagement with a counter-part magnetic buckle. The magnetic member holder portion includes a base portion (22) which preferably conforms closely to the base dimensions of the magnetic member and an upstanding fencing wall (23) which extends upwardly along the perimeter of the base portion. The combined structure of the base portion together and the peripheral fencing wall provides a cavity casing within which the magnetic member is received with the magnetic coupling surface (11) exposed and unobstructed. The cavity casing, which includes the base portion (22) and the upwardly extending parametric peripheral wall (23), is preferably made of a magnetic material, for example, a ferro-magnetic substance such as chromium or Nickel plated steel. The magnetic member can be glued to the cavity housing or retained by other means, including mechanical retention or embedment. When the magnetic member is enclosed by a magnetic material and with an exposed surface, the magnetic strength of the exposed magnetic surface will be reinforced and maximized, and the magnetic coupling forces, when coupled with the opposite magnetic surface (10) of a similarly designed counterpart magnetic buckle, will be greatly enhanced when compared to magnetic members not so encased. With such a design, a more compact buckle with a strong magnetic strength can be provided.

The strap receiving portion (25) includes a means (24) for receiving or otherwise connecting to the flexible end of a flexible strap. To enhance secured retention of the strap, the receiving portion may include a serrated slot or notch.

The strap receiving portion (25) includes a means (24) for receiving the flexible end of a flexible strap in order to form a strap with a buckled end. To improve better retention of the strap end, the receiving portion may include a serrated slot or notch. In order to provide a low-profile buckle design, the strap receiving portion is relatively thin with a thickness which is preferably equal to or less than that of the peripheral wall of magnetic member. In addition, the strap receiving portion is preferably formed by placing it adjacent to the peripheral edge joining the magnetic polar surfaces rather than extending from either polar surfaces so that an over-all low-profile structure can be obtained.

In the present embodiment, the strap receiving portion contains a rigid bridging portion which extends away from the cavity casing in a lateral or radial manner. In this arrangement, the strap receiving portion is substantially equidistant from both polar surfaces and is joined to the cavity casing by the rigid bridging portion (27). The bridging portion (27) preferably includes a ribbon- shaped plate member with its wide surfaces substantially parallel to the magnetic coupling surfaces (11, 12). Of course, instead of ribbon shaped member, a thin shaft member may be used to join the strap receiving portion and the cavity casing. In any event, the portion of the housing which extends away from the cavity casing should be of a slim design so that an overall low-profile design can be achieved.

For example and as shown in the Figures, a substantial portion of that extension is

preferably flat and the whole portion should be kept within the height of the

peripheral wall of the magnetic member (10). Alternatively, the strap-receiving

means may be formed proximate and adjacent to the peripheral wall joining the

polar surfaces (11, 12) so that it is substantially equi-distant from both polar

surfaces (11, 12). Forming the strap-receiving means sidewise of the polar surfaces

will always provide a desirable low-profile structure.

Referring now to Figure 4 in which there are shown a pair of complementary counterpart magnetic buckles in magnetic engagement, it can be

seen that the magnetic coupling surfaces of the counterpart buckles A and B with

magnetic coupling surfaces (11) of the opposite magnetic polarities are in physical

contact. It should be noted that while it is preferable that both of the

complementary buckles are of the same structural design as mentioned herein, a

buckle of a different design but of a complementary nature can be used as a

counterpart buckle or fastener.

As can be seen from this Figure, the laterally or radially extending strap

receiving portions help to reduce the overall thickness of the engaged buckle pair,

making the assembly particularly suitable for use in circumstances, for example in

lingerie and brassiere applications, where a thin assembly is desirable. Furthermore, in order to alleviate the risks of undesirable or accidental disengagement of the magnetically coupled buckle pairs, the portion of the peripheral wall at the end of the cavity casing directly opposing the strap receiving portion is made with a small projection or with an elevated teeth (26) resembling portion. The protruding portion (26) of the buckle is formed on the cavity wall (23) and extends beyond the surface of its magnetic coupling surface (11). This projection (26) will become a barrier member to the magnetic member (10) of the counterpart buckle by extending also beyond the magnetic coupling surface (11) of the counterpart buckle. With the elevated portion engaging with the edge of the magnetic member of the corresponding counterpart buckle, undesirable lateral slippage in both the left and right directions, i.e., directions along both strap receiving portions can be greatly alleviated. When the buckles are to be uncoupled, a user only needs to slightly lift one of the buckles, for example, by pivoting against the counterpart buckle and then separating the buckles. To ensure sufficient space for accommodating the protruding member (26) without having to press against the bridging portion, a slight indentation corresponding to the location of the protruding portion is preferably provided so that the teeth (26) can rest above and away from the bridging portion. This slight indentation may also be accompanied by a discontinuation of the perimetric wall at the corresponding position to allow engagement of the teeth member. As shown in the Figures, the indentation is formed at the intersection or junction between the bridging portion and the cavity housing. In the present specific example, the housing is integrally formed of a magnetic material so that one of the magnetic surfaces is in contact with the base portion while the peripheral wall of the magnetic member is enclosed within the cavity housing, leaving the magnetic coupling surface exposed. Where a ring- or toroidal-shaped magnet member is used, the cavity housing may have a hollow base portion. To provide a decoration or an aesthetic design, the buckle may be enclosed within a thin magnetic permeable enclosure made, for example of, PVC, synthetic resins, rubber, Nylon or the like material. Furthermore, while the

permanent magnet (10) is held by a holder portion which is made preferably of a magnetic material in order to strengthen and concentrate the magnetic force on the exposed polar surface of the permanent magnet, it should be appreciated that the present invention can be made by having a magnetic enclosed within a housing which does not have the effect of concentrating the magnetic strength on a particular polar surface as long as there is provided a strap receiving means transverse or side- wise to the magnetic axis of the permanent magnet.

In another embodiment of the present invention as shown in Figs. 5 A to 5B, a strap fastener (50) contains a housing (52) and a magnetic member (56) similar to the one described in the previous embodiment including strap receiving portion (54) and receptacle (52c). Receptacle (52c) contains a base portion (52a) and side wall (52b). In this embodiment, the base portion (52a) is circular in shape with one side (54a) extending outwards to connect with the strap receiving portion (54). A magnet (56) of the same dimension as the base portion (52a) is provided for attachment into the receptacle (52c). In this embodiment, another strap fastener (60) having a housing portion (62) with a strap receiving portion (64) is provided

to engage the first fastener (50) for proper functioning of this pair of fasteners. The

base portion (62a) of the second fastener (60) is larger in diameter compared to the

base portion (52a) of the first fastener (50). Another magnet (66) larger in diameter

than the first magnet (56) is provided for attachment into the receptacle area (62c)

of the larger fastener (60). The perimeter wall (62b) of the larger fastener (60) is

higher than the height of the attached magnet (66) as shown in Fig. 5B. As in the

smaller fastener, the base portion (62a) of the larger fastener (60) is connected to

the strap receiving portion (64) via an extended side (64a).

During operation, the smaller fastener (50) is attached to the larger fastener

(60) as shown in Fig. 5D. As the side wall (62b) of larger fastener (60) is higher

than the magnet (66) attached, the smaller strap fastener (50) will engage larger

fastener (60) in a manner such that the extended portion of the side wall (62b) will

act as a stopping mechanism to prevent lateral movement between smaller fastener

(50) and larger fastener (60). To disengage the two fasteners, a twisting force or

pulling force in a direction substantially parallel to the magnetic axis (70) may be

used in a single action. No further action is required to disengage the stopping

mechanism.

As can be seen by the previous discussion, the phrase "substantially parallel

to the magnetic axis" is meant for ease of understanding and includes a twisting

action to pull a pair of magnetic fasteners apart. In another embodiment shown in Figs. 6A to 6E, the strap fastener (82)

according to another embodiment of the present invention has a housing containing

a receptacle (80) and a strap fastening portion (84) similar to the previous

embodiments. The main difference in this embodiment is that the peripheral wall

(82b) that is attached to the circular base portion (82a) of the receptacle (80) of the

strap fastener (82) is bevelled with a tall end (82d) and a short end (82e). The tall

and short ends are preferably on opposite sides of the circularly shaped base

portion (82a) with the short side (82e) adjacent the strap fastening portion (84).

The magnet (86) has a thickness that is shorter than the tall end (82d) of the

peripheral wall, but approximately the same height as the short end (82e) as shown

in Fig. 6B. As in the other embodiments, a connecting area (84a) connects the

strap fastening portion (84) to the receptacle (82). The connecting portion (84a) is

extending outwards from the base portion as shown in Fig. 6B and Fig. 6C.

During fastening engagement, as shown in Fig. 6D, two bevelled fasteners

with facing magnetic poles attracting each other according to the present

embodiment maybe engaged in facing directions with the tall end of the wall (82d)

coupled to the short end (82e) of the wall. In the preferred embodiment, the tall

end (82d) is tall enough to extend within the extended portion (84a). It is clear

from the description above that lateral movements parallel to the strap fastener

portion and perpendicular to the magnetic axis (89) is restricted as the engagement

of the tall end with the short end together with the bracing action of the strap

fastening portion acts as the stopping mechanism in the present embodiment. The

advantage of this embodiment is that lateral rotational movement between the two engaged fasteners is minimized due to the restrictions engaged by the two bevelled walls when they are functionally engaged.

While the magnet in the above description is described as being discshaped, it is clear that any magnetic element that can function within the receptacle and contains the features as claimed in the following claims would fall within the scope of the present invention. As shown in Figs. 7A to 7E, the magnet according to the present invention may also be of a ring shape as shown by reference numeral 80 of Fig. 7C. A base plate (82), preferably with a raised internal circular portion (82b), is preferably provided for attachment onto the magnetic ring (80). The entire magnetic element (including plate (82) and ring (80)) can then be used like a magnet for attachment to the receptacle in the fastening. For example, the magnet shown in reference numerals 86, 56 and 66 may actually consist of a magnetic ring and a metallic disk as shown in Fig. 7B. The advantage of such a magnetic set is that expensive magnetic material may be reduced due to the hole in the centre of the ring. This, however, does not substantially reduce the magnetism of the magnet set because the base plate may be made of a ferro-magnetic substance such as chromium or of Nickel plated steel that can concentrate the magnet along magnetic axis (88) and in the direction unshielded by the base plate. The base plate is the side of the magnetic set that is attached to and adjacent the base portion of the previous-described fasteners while the magnetic ring is exposed for interaction with another magnetic attached to a matching fastener. Referring to Figs. 8A-8D, the fifth preferred embodiment of the magnetic

fasteners include a pair of fastening members with complementary magnetic and

mechanical properties. Each of the constituting magnetic fastening members 501,

502 includes a magnetic member receptacle or holder 521, a magnet member 510

and a fastening means. The magnet member 510 is preferably a permanent magnet

made of a strong magnet or a strong magnetic alloy. The magnet member 510 in

the present preferred embodiment is pellet shaped with an aperture 550 at the

center so that the fastening means can bind the magnet member 510 via the

aperture 550. The magnet member 510 includes a first magnetic coupling surface

511 of a first magnetic polarity and a second magnetic surface 512 of a second and

opposite magnetic polarities. The magnet member receptacle 521 includes a base

portion 522 for comfortably receiving the second magnetic surface 512 so that,

preferably, the second magnetic surface 512 of the magnetic member closely

contacts the base portion 522 of the receptacle.

The receptacle further includes a strap fastening means 525 extending

generally in a direction which is substantially orthogonal or normal to the magnetic

axis of the magnet member 510. As is apparent from the Figures, the magnetic axis

generally perpendicular to the first magnetic coupling surface 511 and the second

magnetic surface 512 of the magnet member 510.

The strap fastening means preferably includes an elongated slot 524 which extends generally perpendicular to the direction of extension of the fastening

means as a whole. With this arrangement, a strap of a definite width can be received comfortably within the elongated strap receiving slot while the strap as a whole extends generally perpendicularly away from the magnetic axis of the magnet member.

The base portion 522 of the magnet receptacle is preferably made of a ferro- magnetic material so that the magnetic flux originating from the second magnetic

surface of the magnet member will concentrate on the base portion 525 of the

magnet member receptacle. A fastening means which is a fastening member 560 similar to a rivet is used in the present embodiment to fasten the magnetic member to the base portion of the magnet member receptacle. This fastening rivet 560 is preferably made of a ferro-magnetic material so that the magnetic flux can be concentrated further at the portion which protrudes above the first magnetic coupling surface 511 of the magnet member. In general, this fastening member is riveted along an axis generally parallel to the magnetic axis to the base portion of the magnetic holder.

The constituting part of the corresponding fastening member 502 also includes a magnet member receptacle, a magnet member and a fastening means. The magnet member receptacle and the magnet member are generally identical to that of the corresponding members. The fastening means for the fastening member shown in Fig. 8C is generally similar to that shown in Fig. 8B with the exception that the top end of the fastening means is provided with a female socket portion for receiving the protruding plug portion of the fastening means of Fig. 8B. The top part of this female portion is generally frusto-conical shaped and is preferably wholly embedded within the central aperture 550 of the magnet member of the

fastening member 501 so that the protruding portion of the male member of the fastening means of Fig. 8A can be totally received within the depression formed within the circumference of the frusto-conical shaped member.

With this arrangement, the magnetic fastening members can be magnetically coupled to each other with the first magnetic coupling surfaces 511 of the corresponding magnet members in contiguous contact and with the pair of fastening means mechanically and magnetically engaged, thereby providing additional mechanical security to avoid undesirable or accidental lateral disengagement. It will be noted that although additional security is provided, this magnetic fastening pair is still provided with the benefit of easy disengagement. To disengage a magnetic coupled fastener pair, a user can simply depress the strap

fastening portion 525 of the magnet member 510 receptacle so that the distal-end of the base portion of the receptacle is lifted. With the slight elevation of the distal-end of the receptacle, the magnetic fastener pair can be separated, for example, by turning about the instantaneous pivotal contact between the two magnet members to dis-align the fastening means and then to separate the pair.

Although it is not strictly necessary, it is preferred that the magnet member receptacle is integrally made of a ferro-magnetic material, and, preferably, from a ferro-magnetic sheet of thickness not exceeding that of the thickness of the magnetic member, which is the general separation between the first and second magnetic surfaces of the magnetic member. Referring to Figs. 9A-9C, there is shown a sixth preferred embodiment of

the magnetic fasteners including a pair of fastening members 601, 602 with complementary magnetic and mechanical properties generally similar to that of the embodiment shown in Figs. 5A-5E. i this embodiment, the magnet member receptacle includes a main housing 620 and a casing 670 made of a ferro-magnetic material. The ferro-magnetic casing is shaped to correspond with the general

dimension of the magnet member 610 so that one of the magnetic polar surfaces (the second magnetic surface) 612 of the magnet member is in close or contiguous contact with the bottom surface of the ferro-magnetic casing 670 while the side or peripheral wall of the magnetic member is substantially surrounded by the

upstanding circumferential wall 623 of the ferro-magnetic casing. The magnet

member 610 is secured to the ferro-magnetic casing, for example, by gluing, bonding, spot welding or mechanical clamping. The mechanical sub-assembly comprising the magnet member 610 and the ferro-magnetic casing 670 is then secured to the base portion 622 of the main housing of the receptacle.

A strap receiving means 625 similar to that described in the aforementioned preferred embodiments and extending in a similar manner is also provided as an extension to the main housing 620. The base portion of the

receptacle 620 includes a cavity for tightly receiving the magnetic sub-assembly

comprising the magnet member 610 and the ferro-magnetic casing 670. The sub- assembly can, for example, be secured to the receptacle by adhesive gluing, bonding or other appropriate securing means. The cavity for receiving the magnetic sub-assembly includes a circumferential upstanding wall 623 surrounding the peripheral wall of the magnetic sub-assembly. The far-end of the main receptacle housing, which is the end away from the strap fastening means, is provided with a protruding portion 626 while the near end of the main receptacle

housing adjacent to the strap fastening means 625 is provided with a

complementary depression 628. It will be observed from Fig. 9C that the respective protrusion 626 and depression 628 formed on the main receptacle

housing 620 form a complementary mechanical pair to provide additional securing to alleviate the risk of undesirable lateral relative movements between the two

constituting fastening members 601, 602. To separate the two fastening members, a user simply needs to depress the strap fastening end of the fastener and cause the fastener to turn about the momentary pivotal point to dis-align the two fastening members for easy subsequent separation.

In this preferred embodiment, it will be noted that the ferro-magnetic cavity with its surrounding circumferential wall provides a receptacle to the magnet member as well as concentrating the magnetic flux along the free end of the circumferential wall 623 so that the magnetic coupling between the upstanding circumferential walls of the two corresponding or complementary fastening members 601, 602 will be concentrated or strengthened along the circumferential walls 623 to improve magnetic coupling between the two constituting fastening members. Referring now to the seventh embodiment shown in Figs. 10A-10C, the

pair of magnetic fasteners includes a first and a second fastening members 701,

702. The first fastening member is generally similar to that describe in Fig. 9

although the upstanding circumferential wall 723 of the ferro-magnetic housing

generally protrudes and elevates above the first magnetic coupling surface 711 of

the magnetic member 710 and above the general surface of the main receptacle.

The second fastening member 702 is generally similar to the embodiment

of Figs. 1-4 and includes a magnet member receptacle 720 having a base portion

722 made of a ferro-magnetic material and surrounding the magnet member 710.

The magnet member receptacle 720 of the second fastening member 702 is formed

with a cavity having a surrounding wall 723 with a depth less than the thickness of

the magnet member 710. When the magnet member 710 is securely received

within the cavity of the magnet member receptacle 720 of the second magnetic

fastening means, a circumferential portion of the magnet member 710 is exposed

above the circumferential wall of the receptacle. The height of the exposed portion

of the magnet member 710 of the second fastening member 702 is generally equal

to the depth of the upstanding circumferential wall extending above and beyond the

first magnetic coupling surface 711 of the magnetic member 710 of the first

fastening member 701. When the two magnetic fastening members are coupled,

the magnetic coupling surfaces of the corresponding magnetic members will be in

contiguous contact while the protruding circumferential wall of the ferro-magnetic

casing of the first magnetic member will be in contiguous contact with the ferro- magnetic portion of the base portion 722 of the ferro-magnetic portion of the

receptacle 720 of the second fastening member 702. Similar to the principles

described for the afore-mentioned embodiments, magnetic fluxes will be

concentrated along the upstanding circumferential wall 723 of the ferro-magnetic

casing of the first magnetic member and magnetic coupling will be strengthened or

concentrated along the protruding circumferential wall when magnetically coupled

with the ferro-magnetic portion of the main receptacle of the second magnetic

members. The elevated circumferential wall extending above the first magnetic

coupling surface of the magnetic member of the first magnetic fastening member

also provides additional securing between the coupled pairs. Similarly, the

magnetic coupled pairs can be easily disengaged by a user pressing or depressing

the strap fastening means 725 in a direction substantially parallel to the magnetic

axes of the magnetic members. Apart from the differences mentioned above, the

general mechanical structure of this embodiment is substantially similar to the

afore-mentioned general embodiments.

Turning now to the seventh embodiment as shown in Figs. 11A-11C, the

magnetic fasteners include a first 801 and a second 802 magnetic fastening

members with complementary magnetic and mechanical properties. Each of the

constituting magnetic fastening members include a magnet member receptacle 820

or holder and a magnet member 810 which is preferably a permanent magnet made

of a strong magnetic alloy. The magnet member receptacle 820 generally includes

a base portion 822 having a bottom surface adapted to receive one of the polar

surfaces of the magnet member 810. A strap fastening means 825 with a strap receiving aperture 824 generally extends away from the base portion in a direction which is substantially orthogonal or perpendicular to the magnetic axis of the

magnetic member 810. h general, the bottom surfaces of the receptacle and strap fastening means are generally parallel to each other. Preferably, the magnetic member receptacle is integrally formed from a ferro-magnetic shaped so that the base portion and the strap fastening means are integrally formed as a single unit. In this preferred embodiment, the magnet member 810 of the first fastening member

801 is disposed on the base portion at a distal location generally away from the strap fastening means 825. The peripheral surface of the magnet member which is opposite to the strap fastening means 825 is adapted to be complementary to the

corresponding interfacing surface of the magnetic member 810 of the corresponding magnetic fastening member 802. When the magnetic fastening members of a similar design but with complementary magnetic properties are coupled together, the exposed magnetic coupling surface of one of the constituting magnetic fastening member will be magnetically coupled to the exposed bottom

portion of the ferro-magnetic base portion 822 of the receptacle main housing 820.

Furthermore, the complementarily shaped interfacing surfaces 880 on the corresponding magnetic members provide further and additional mechanical security to restrict relative movements of the constituting magnetic fastener parts to move away from each other along the general direction of extension of the strap

fastening means 825. Similarly, although additional mechanical means has been integrally provided to restrict relative lateral movement along the direction of the strap fastening means, the magnetic fastening pair can be easily separated by pivotal depression of the strap fastening means about the distal edge of the magnetic member of the corresponding magnetic member for easy removal.

While the present invention has been explained by reference to the preferred embodiments above, it should be appreciated that the embodiments are provided for illustration and assisting understanding only and do not intend to limit or restrict the scope of the present invention. For ease of description, the polarity of the magnetic members of each of the fasteners have not been specifically stated. It is however clear for one of ordinary skilled in the art that for a pair of fasteners

to work according to the present invention, each pair of functionally engaged fasteners would have magnetic members of opposite polarity facing each other in the two matching fasteners.

Claims

1. A fastener including a housing and a magnetic member, said magnetic member including a first surface and an opposing second surface corresponding to a first magnetic pole and a second magnetic pole

respectively, said first and second magnetic pole defining a magnetic axis therebetween, said housing including

a receptacle for receiving said magnetic member;

a strap receiving means extending from said receptacle; and

a stopping mechanism provided in said housing adapted to engage a matching fastener containing a matching housing and matching magnetic member, said stopping mechanism preventing lateral slippage therebetween and in a direction substantially perpendicular to said magnetic axis, said stopping mechanism further capable of being simultaneously disengaged by a single action to pull said fastener and said matching fastener apart along a direction substantially parallel to said magnetic axis.

2. A fastener of Claim 1, wherein said receptacle includes a base portion and a wall extending upwardly from the perimeter of said base portion, one surface of said magnetic member attached to said base portion and said wall is adapted to surround the peripheral wall of said magnetic member.

3. A fastener of Claim 2, wherein said wall discontinues at about the junction between said strap receiving means and said base portion.

4. A fastener of Claim 1, wherein said receptacle includes a wall surrounding the peripheral wall of said magnetic member, said wall includes an elevated portion protruding beyond the exposed magnetic surface.

5. A fastener of Claim 4, wherein said elevated portion is adapted so that when said strap fastener is magnetically coupled with a counter-part strap fastener of the same design, said elevated portion will not push against the strap receiving means of the counter-part fastener while forming a barrier member to stop relative lateral movement along the directions of the strap receiving means.

6. A fastener of Claim 4, wherein said protruding portion is located substantially diametrically opposite the axis of said strap fastener.

7. A fastener of Claim 1, further including a projection which is disposed on the edge of said receptacle at a position which is substantially opposite to said strap receiving means and which extends beyond said exposed polar surfaces.

8. A fastener of Claim 1, wherein said magnetic member is a disc-shaped magnetic slab.

9. A fastener of Claim 1, wherein said magnetic member is ring-shaped.

10. A strap fastener of Claim 1, wherein said magnetic member includes a disk member having a protruding portion extending axially from one of the magnetic surfaces.

11. A fastener of Claim 1, wherein said housing is made of a ferro-magnetic material.

12. A fastener of Claim 1, wherein at least said receptacle is made of a ferromagnetic material.

13. A fastener of Claim 1, wherein said housing is made of a ferrous material with Nickel or Chromium plating.

14. A fastener of Claim 1, wherein said strap receiving means includes a buckle member having a substantial planar portion for receiving a strap.

15. A fastener of Claim 1, wherein said strap receiving means includes a buckle having a substantial planar slot.

16. A fastener of Claim 1, wherein said receptacle includes a bracket for receiving said magnetic member.

17. A fastener of Claim 1, wherein said strap receiving means is substantially equi-distant from said first and second polar surfaces.

18. A fastener according to Claim 2 wherein said matching magnetic member includes a matching first surface and a

matching second surface defining a second magnetic axis therebetween;

wherein said matching housing includes a matching receptacle with a

matching base portion and a matching wall have a first end attached to

said base portion and a free end extending upward from the perimeter of

said matching base portion,

said matching magnetic member attached to said receptacle with one

surface of said matching magnetic member adjacent to said matching base

portion and the free end of said matching wall extending beyond said

matching second surface, said matching wall further having a perimeter

larger than the perimeter of said wall and said base portion such that said

free end of said matching receptacle surrounds said receptacle when said

fastener and said matching fastener are functional engaged.

19. A fastener according to Claim 2 wherein said wall is bevelled with

opposing tall and short sides, said short side proximate said strap

receiving means and said tall side distal therefrom.

20. A fastener including a housing and a magnetic member, said magnetic

member including a first surface and an opposing second surface

corresponding to a first magnetic pole and a second magnetic pole

respectively, said first and second magnetic pole defining a magnetic axis

therebetween, said housing including a receptacle for receiving said magnetic member and a strap receiving means extending therefrom, said receptacle having a close end and an open end, said first surface of said magnetic member attached to said close end of said receptacle, said second surface of said magnetic member substantially exposed through said open end of said receptacle.

21. A fastener according to Claim 20 wherein said housing is made of a ferromagnetic material.

22. A fastener according to Claim 20 wherein said receiving means extends a way from the peripheral wall in a direction substantially perpendicular to the magnetic axis.

23. A fastener comprising a pair of engageable magnetic fasteners of opposite polarity to each other engageable on a common axis and a strap engagement portion connected to each magnetic fastener and extending transverse to said common axis of engagement of said magnetic fasteners.

24. A fastener according to Claim 23, further including at least one protrusion to reside against a perimeter of an opposed magnetic fastener to resist movement of one magnetic fastener with respect to the other transverse to said common axis on which they engage.