GB2178105A

GB2178105A - Locking sliders for zip fasteners

Info

Publication number: GB2178105A
Application number: GB08518389A
Authority: GB
Inventors: Kenneth Russell
Original assignee: RHONDDA PRESSINGS Ltd
Current assignee: RHONDDA PRESSINGS Ltd
Priority date: 1985-07-20
Filing date: 1985-07-20
Publication date: 1987-02-04
Also published as: IT208058Z2; GB8518389D0; IT8653654V0; GB2178105B

Abstract

A slider for a zip fastener comprises a body (1) from which projects a puller (2). A control spring member (3) is fixed to the body (1) by lugs (14) and it defines support arches (9) which hold a bar (10) of the puller (2) in place. A central portion (8) of the control spring member (3) extends via a leaf spring portion (7) to a cam-control portion (12), positioned over a cam carried by the puller bar (10) terminating in a locking pawl (19). When the puller (2) lies flat the locking pawl (19) locates between teeth of the zip and when the puller (2) is raised the cam on the puller bar (10) lifts the locking pawl (19) out of engagement. The body (1) is recessed on its top face to receive the spring member (3) so that a compact slider of minimal height is achieved. <IMAGE>

Description

SPECIFICATION Improvements relating to sliders for zip fasteners This invention is concerned with a type of slider for a zip fastener termed a "flat lock slider", comprising a slider body which controls opening and closing of the zip, a puller to be grasped between the fingers of the user, and a spring carrying a locking pawl which is effective to prevent movement of the slider when the puller is in a closed position.

It is an object of this invention so to construct the parts of such a slider, particularly a control spring member thereof, that the height of the slider will be relatively small and the operation of the control spring member will be particularly effective.

Accordingly, from one aspect, this invention provides a control spring member for a flat lock slider of a zip fastener, the spring member comprising side support arms defining a pair of raised support arches for retaining the puller bar of the puiler of the slider, and a central portion integral at one end only with the support arms and defining a leaf spring portion, an arched cam-control portion to pass over the cam in the centre of the puller bar of the puller of the slider, and a locking pawl directed downwardly to be able to pass through the body of the slider.

This design of control spring member is particularly suitable because it provides for a secure mounting for the puller without affecting the operation of the leaf spring portion itself to which the locking pawl is attached. This is because the central portion is essentially separate from the side support arms, by means of which the control spring member may be staked to a body of the slider. It is preferred that the support arms should be joined together at the end remote from their interconnection with the central portion for added rigidity for these parts. Ideally gaps will be defined between the sides of the support arms and the central portion for receipt of staking lugs for securing the spring member to the body of the slider.

The invention also extends to a flat lock slider for a zip fastener comprising a slider body, a puller, and a control spring member of this invention as hereinbefore defined, staked to the body to retain the puller so that the puller bar of the puller is rctatable within the support arches and the arched cam-control portion of the spring member, and the locking pawl projects through the body when the puller is in the closed position.

In the preferred arrangement the support arms of the spring member lie in a plane from which project the support arches and the top surface of the body is recessed to a depth to receive the parts of the spring member lying in said plane. By recessing the spring member into the body the depth of the slider is reduced as compared with an arrangement wherein the spring member is mounted over the top surface of the body. The latter arrangement, utilising the control spring member of this invention may prove satisfactory for certain purposes, but generally it is desirable to keep the depth of the slider as small as possible. Advantageously the leaf spring portion of the spring member will also lie in the aforesaid plane of the spring member.It is also preferred that the recess should be restricted in width below the support arches of the spring member to define support platforms for the ends of the puller bar of the puller.

The spring member is ideally staked by lugs projecting from the body to pass on the inner edges of the support arms and then overlie those support arms. However, it will be appreciated that staking could alternatively be achieved by arranging for the lugs to pass on the outer edges of the side support arms (or ends of the spring member integral with the side support arms) and then turn inwardly to overlie the relevant parts of the spring member without interfering with the movement of the central portion of the spring member.

The invention may be performed in various ways and a preferred embodiment thereof will now be described with reference to the accompanying drawings, in which: Figure 1 is a perspective view of a flat lock slider for a zip fastener constructed in accordance with this invention; Figure 2 is a plan view of a control spring member of the slider, Figure 3 is a vertical section on line Ill-Ill of Figure 2, Figure 4 is an end view of the spring member of Figure 2, Figure 5 is a plan view of the body of the slider, Figure 6 is a partial vertical cross-section on line VI--VI of Figure 5, Figure 7 is a vertical section on line VIl-VIl of Figure 5, Figure 8 is a plan view of a puller of the slider, and Figure 9 is a section on line IX-IX of Figure 8.

The slider illustrated in the drawings comprises a body 1, a puller 2, and a control spring member 3. As can be seen from Figures 5 to 7 the top surface of the body 1 is recessed at 4 to receive parts of the spring member 3. The main parts of the spring member received within the recess are side support arms 4 joined together at the rear by a web 5 and at the forward end by a web 6, together with a leaf spring portion 7 of a cen tral portion 8 of the spring member 3. Support arches 9 project up from the side arms 4 to retain a puller bar 10 of the puller 2. The ends of the puller bar 10 rest on support platforms 11 of the body 1 at a position where the recess 4 is restricted in width.The central portion 8 of the spring member 3 also defines an arched cam-control portion 12 which covers, lies and is in contact with a cam 13 carried by the puller bar 10 (Figures 8 and 9). The terminal limb of the cam-control portion 12 extends downwardly to define a locking pawl 19 (Figures 3 and 4).

As can be seen from Figures 2 and 3 in particular, open areas are defined between the support arms 4 adjacent to the web 6 of the spring member 3, and also between the side support arms 4 and the leaf spring portion 7.

These provide openings through which pass four lugs 14 defined as part of the body 1 and which are bent over to stake down the control spring member 3 without interfering with the flexing movement of the central portion 3 as allowed by the leaf spring portion 7.

When the control spring member is staked dwn in this way the puller bar 10 will be securely positioned (vertically and longitudinally) although allowed to rotate, whilst the arched cam-control portion 12 will bear down onto the cam 13. When the puller 2 is in a closed position where it lies down generally parallel with the body 1 in the direction towards the web 6, the flat region 15 (Figure 9) of the cam 13 will be contacted by the camcontrol portion 12 and the locking pawl 19 will project into the interior 16 between the top and bottom shields 17,18 of the body 1 so that the locking pawl will engage with the teeth of the zip and prevent the slider from moving up and down the zip.However, as the puller 2 is lifted, to rotate the puller bar 10, beyond a position of 30 to 40O from the horizontal, the cam 13 will lift the cam-control portion 12 so as to remove the locking pawl from the space 16, thus enabling the slider to be moved freely up and down the zip. The shape of the cam 13 is such that the locking pawl 19 is disengaged from the initial disengaging position over to the position wherein the puller 2 again lies substantially parallel with the body 1, but in a direction towards the web 5. The parts 1,2 and 3 may be formed from any conventional robust material, preferably by pressing. It is an advantage that the slider may be assembled automatically in a single stage process wherein the lugs 14 are turned down onto the central spring member 3. The puller may readily be formed for use with any conventional type of zip.

Claims

1. A control spring member for a flat lock slider of a zip fastener, the spring member comprising side support arms defining a pair of raised support arches for retaining the puller bar of the puller of the slider, and a central portion integral at one end only with both support arms, the central portion defining a leaf spring portion, an arched cam-control portion to pass over the cam in the centre of the puller bar of the pul!er of the slider, and a locking pawl directed downwardly below the plane of the support arms to be able to pass through the body of the slider.

2. A spring member according to claim 1, wherein the support arms are joined together at the end remote from their interconnection with the central portion.

3. A spring member according to claim 1 or claim 2, wherein gaps are defined between the sides of the support arms and the central portion for receipt of staking lugs for securing the spring member to the body of the slider.

4. A control spring member for a flat lock slider of a zip fastener substantially as herein described with reference to the accompanying drawings.

5. A flat lock slider for a zip fastener comprising a slider body, a puller, and a control spring member according to any one of claims 1 to 4 staked to the body to retain the puller so that the puller bar of the puller is rotatable within the support arches and the arched camcontrol portion of the spring member, and so that the locking pawl projects through the body when the puller is in the closed position.

6. A slider according to claim 5, wherein the support arches project from the plane of the support arms of the spring member and the top surface of the body is recessed to a depth to receive the parts of the spring member lying in said plane.

7. A slider according to claim 6, wherein the leaf spring portion of the spring member also lies in said plane.

8. A slider according to claim 6 or claim 7, wherein the recess is restricted in width below the support arches of the spring member to define support platforms for the ends of the puller bar of the puller.

9. A slider according to any one of claims 5 to 8, wherein the spring member is staked by lugs projecting from the body to pass on the inner edges of the support arms and then overlie those support arms.

10. A flat lock slider for a zip fastener substantially as herein described with reference to the accompanying drawings.