GB2195390A

GB2195390A - Self-engaging securement foot

Info

Publication number: GB2195390A
Application number: GB08623152A
Authority: GB
Inventors: Lawrence S Ting
Original assignee: Taiwan Industrial Fastener Corp
Current assignee: Taiwan Industrial Fastener Corp
Priority date: 1986-09-26
Filing date: 1986-09-26
Publication date: 1988-04-07
Also published as: GB8623152D0

Abstract

A self-engaging securement foot, adapted for fitting on the bottom of luggage such as suitcases, bags and knapsacks, comprises a plastics stud 1 having at one end spaced annular ridges 13, and a plastics socket 2 provided at the center thereof with a radially slotted conical hole, forming a plurality of radial tongues 26. The stud 1 is capable of being pressed-in from the top of the socket 2 until the ridges 13 snap post the tongues 26. The stud 1 can thus be firmly secured to the socket 2 to trap therebetween a support A, such as the bottom of a suitcase, bag or knapsack. <IMAGE>

Description

SPECIFICATION Self-engaging securement foot The invention relates to a self-engaging securement foot capable of being secured to the bottom of luggage, such as suitcases, bags and knapsacks.

At present, a suitcase for example is usually provided on the bottom thereof with four securement feet of generally truncated conical shape or semi-spherical shape. Each of the securement feet is obtained by moulding a metal pin in a truncated conical or semi-spherical plastics stud so that the upper end of the pin is protruding. In fitting, the metal pin of the stud is passed from the outside into a small preformed hole in the bottom of the suitcase. A washer is then sleeved on to the metal pin within the suitcase. The head of the pin is then bent over the washer to prevent loosening of the engagement. Since this type of securement foot requires moulding of the metal pin inside the plastics stud, the moulding not only takes a lot of work and time but the production cost also rises correspondingly.

Furthermore, during mounting of the securement foot it is necessary to sleeve a washer on first and then secure the securement foot in position by flattening the end of the metal pin from inside the suitcase. Hence the assembly process is difficult to manage and this will in turn affect the production speed.

In accordance with the present invention, however, a self-engaging securement foot comprises: a plastics rivet member having a shank with a head at one end thereof and a plastics stud member provided with a central opening therethrough; said rivet member has a plurality of spaced-apart protruding annular ridges on the shank, each of the annular ridges having an oblique generally conical face directed outwardly towards the head; and said stud member is formed in the central opening with a plurality of petals separated by radial slots to present a generally conical and resiliently deformable lock, whose end initially further from the rivet member is the smaller and is truncated to present a hole for permitting the petals to close towards the shank of the rivet member between the annular ridges; whereby, in use, the shank of the rivet member is capable of being inserted through an apertured member and into the central opening of the stud member, one or more of the oblique generally conical faces on the annular ridges being sequentially snapped past the generally conical and resiliently deformable lock to resist subsequent removal of the rivet member from the stud member.

It will be appreciated that the self-engaging securement foot of the present invention can be simple in construction, easy to manufacture and permit swift mounting, thereby raising the speed of production of luggage.

It will be further appreciated that the annular ridges on the rivet member act as a check, and the generally conical and resiliently deformable lock in the stud member acts as a unidirectional check cone hole, withdrawal of the rivet member from the stud member being extremely difficult if not impossible after they have been locked together.

The shank of the rivet member may be of cylindrical or polygonal cross-section, and the head of the rivet member, on that side thereof facing the shank, may be provided with plurality of sharp piercing needles.

A self-engaging securement foot, in accordance with the present invention, and a modification thereof, will now be described, by way of example only, with reference to the accompanying drawings in which: Fig. 1 is an exploded perspective view of a securement foot constructed in accordance with the present invention; Fig. 2 is a front view of a rivet member of the securement foot shown in Fig.1; Fig. 3 is a top view of a stud member of the securement foot shown in Fig. 1; Fig. 4 is a sectional view taken along the line IV-IV of Fig.3; Figs. 5,6 and 7 are schematic sectional views showing different stages in mounting the securement foot; and Figs. 8 and 9 are respectively front and underneath views of an alternative rivet member in a modification of the present invention.

Referring to Fig.1, there is shown a securement foot comprising a rivet member 1 and a stud member 2. These two elements are formed by injection moulding of plastics materials (e.g.PP,PE). The rivet member 1 has a flat rounded head 11 and extending vertically downwardly from the bottom of the head 11 is a shank 12. Formed on the lower end portion of the shank 12 is a plurality of spacedapart annular ridges 13, each of the annular ridges 13 being provided at the lower side thereof with a conical face 14 (Fig.2). The contour of the stud member 2 is a truncated cone tapering as illustrated, and for saving in the material is designed as an outside cone barrel 21 and an inside circular barrel 22 joined to each other at the lower end.As shown in Figs. 3 and 4, the inner edge of the circular barrel 22 has at the upper end a larger inner-diametered opening 23 and at the lower end a smaller inner-diametered opening 24. Where the two openings meet there is provided a centrally projecting cone cylinder, or lock, and on this cone cylinder is defined a plurality of radial slots 25. The radial slots 25 in turn split the cone cylinder into a plurality of petals 26, and at the center of the cone cylinder is formed a central hole 27.

Turning now to Fig.5, there is shown the securement foot of the invention in assembly, in which the shank 12 of the rivet member 1 is first passed into a preformed hole in an apertured member, such as a support of any kind A, from for example the bottom inner side of the support. The stud member 2 is next placed against the outer side of the hole, being substantially in alignment with the opening 23. On exerting a force on the head 11 of the rivet member 1, in the direction of the arrow, the lower end of the rivet is guided into the aligning central hole 27 by the cone cylinder.Since the inner diameter of the central hole 27 equals the outer diameter of the shank 12, but is smaller than the outer diameter of the annular ridges 13, the conical face 14 at the front of each of the annular ridges 13 on the lower end of the shank 12, on pressing against the petals 26 at the outer edge of the central hole 27, will permit the inner ends of the petals 26 to be pushed apart towards the outside under this force, thus allowing the aperture of the central hole 27 to be expanded so that the annular ridges 13 can pass sequentially through.

As shown in Fig.6, the rivet member 1 is now snapped into the stud member 2. Each annular ridge 13 at the lower end of the rivet member 1 is provided with a conical face 14 in unidirection only. Each time after an annular ridge 13 has pushed apart and passed through the central hole 27 in the center of the petals 26, the force on the petals 26 will disappear thereby permitting the petals 26 to return immediately by their own elasticity. Following this way, there will be a check action developed between the inner edges of the petals 26 and the upper edge of the adjacent annular ridge 13. The rivet member 1 can thus not be pulled out easily in an opposite direction.

Again as shown in Fig.7, although the material in the support A may have a different thickness, the rivet member 1 is nevertheless provided with several annular ridges 13. In so far as it is within the effective range of the annular ridges, the rivet member 1 may be pressed downward continuously to allow the annular ridges 13 to pass one after the other through the central hole 27 till the bottom face on the head 11 of the rivet member 1 abuts the support A. The support A is then held tightly between the rivet member 1 and the stud member 2, and the central hole 27 is then in engagement with an appropriate annu- lar groove (the space formed between two annular ridges).

In order to resist possible relative turninground of the rivet member 1 in the stud member 2, after they have been held together in engagement, the shank 12 of the rivet member 1 may be made into a square post having an inverted angle in each corner, as shown in Figs.8 and 9. While the diameter of the head 11 of the rivet member 1 may be the same as that of the stud member 2, at an outer circumference of the shank on the bottom face of head 11 there may be formed integrally a plurality of sharp piercing needles 15.

In this way, when said rivet and stud are locked in engagement, because of the noncircular shape of the outer edge of the shank the two members will not turn round in relation to each other. Furthermore, during engagement the needles provided on the bottom face of the rivet head will also pierce into the material of the support thereby rendering the entire securement foot also non-rotatable relative to the support.

It will be appreciated that both elements in the securement foot of the present invention are made of plastics by injection moulding, production thereof being very simple and at low cost. Also during fitting, it requires only to hammer the rivet into the stud and in this way the two parts can be riveted as a single body. The securement foot is thus suitable for use with a support of varying thickness and needs no special. tools for fitting. Particularly, the check effect produced by the petals inside the opening of the stud member and the single-bevelled annular ridges at the terminal portion of the rivet member, together with the engaging effect produced by elasticity in the petals, further allows the securement foot to produce highly effective check and self-engaging results and is thus practically useful.

Claims

1. A self-engaging securement foot comprising: a plastics rivet member having a shank with a head at one end thereof and a plastics stud member provided with a central opening therethrough; said rivet member has a plurality of spaced-apart protruding annular ridges on the shank, each of the annular ridges having an oblique generally conical face directed outwardly towards the head; and said stud member is formed in the central opening with a plurality of petals separated by radial slots to present a generally conical and resiliently deformable lock, whose end initially further from the rivet member is the smaller and is truncated to present a hole for permitting the petals to close towards the shank of the rivet member between the annular ridges; whereby, in use, the shank of the rivet member is capable of being inserted through an apertured member and into the central opening of the stud member, one or more of the oblique generally conical faces on the annular ridges being sequentially snapped past the generally conical and resiliently deformable lock to resist subsequent removal of the rivet member from the stud member.

2. A self-engaging securement foot according to claim 1, in which the shank of the rivet member is of cylindrical or polygonal crosssection.

3. A self-engaging securement foot according to claim 1 or claim 2, in which the head of the rivet member, on that side thereof facing the shank, is provided with a plurality of sharp piercing needles.

4. A self-engaging securement foot substantially as hereinbefore described with reference to Figures 1 to 7, or as modified by reference to Figures 8 and 9, of the accompanying drawings.

5. A self-engaging securement foot according to any preceding claim when assembled to an apertured member such as luggage.