WO2011087402A1

WO2011087402A1 - Over -centre fastener

Info

Publication number: WO2011087402A1
Application number: PCT/SE2010/000004
Authority: WO
Inventors: Evert Appelkvist
Original assignee: OJOP SWEDEN AB
Current assignee: OJOP SWEDEN AB
Priority date: 2010-01-18
Filing date: 2010-01-18
Publication date: 2011-07-21
Anticipated expiration: 2012-07-18

Abstract

Over-centre fastener (1) including a base element (3), a lever (2) which is pivotally attached to the base element over a pivot joint (4) having a pivot axis (5) and an engagement element (6) which, at a proximal portion (14), is pivotally supported by the lever (2) and which, at a distal portion, has means for engagement with an engagement member (7). The pivot joint (4) is comprised of first bearing means being integral with the base element (3) so as to be in one piece therewith and second bearing means being integral with the lever so as to be in one piece therewith, the first bearing means is comprised of a shaft unit (10) and the second bearing means is comprised of an open sleeve unit (11) having a radial opening so as to allow radial introduction of the shaft unit into the sleeve unit (11).

Description

OVER-CENTRE FASTENER

FIELD OF THE INVENTION

The invention concerns an over-centre fastener including a base element, a lever which is pivotally attached to the base element over a pivot joint having a pivot axis and an engagement element which, at a proximal portion, is pivotally supported by the lever and which, at a distal portion, has means for engagement with an engagement member.

BACKGROUND OD THE INVENTION

Such an over-centre fastener is previously known from EP 1 556 620 Bl.

Over-centre fasteners are commonly used for securing two objects together such as keeping a lid in a closed position on a box or the like. A first part of the fastener which often has a hook-like shape is thereby attached to one of the objects. A base element of the other part of the fastener is attached to the other object.

An inherent feature of over-centre fasteners is a self- locking property when closed and under lowed. In order to increase safety it is, however, often provided releasable locking members between the lever and the base element of the fastener .

The background art over-centre fastener is working well and is reliable but is somewhat expensive in manufacture and assembly.

AIM AND MOST IMPORTANT FEATURES OF THE INVENTION

It is an aim of this invention to provide an over-centre fastener as defined above providing advantageous further developments over the background art. This aim is achieved in respect of an over-centre fastener as defined, above wherein the pivot joint is comprised of first bearing means being integral with the base element so as to be in one piece therewith and second bearing means being integral with the lever so as to be in one piece therewith, the first bearing means is comprised of a shaft unit and the second bearing means is comprised of an open sleeve unit having a radial opening so as to allow radial introduction of the shaft unit into the open sleeve unit .

Hereby it has been made possible to produce an over- centre fastener of this kind having only two main components which have respective integral bearing means for engagement with one another. This way manufacture and assembly is

simplified and thereby cost of the resulting fastener reduced.

It is preferred that the radial opening of the open sleeve unit is measured so as to allow snap-action

introduction of the shaft unit into the sleeve unit, since this facilitates manufacture and ensures that the elements stay connected.

It is preferred that the shaft unit and the sleeve unit are comprised of axially separate shaft portions and sleeve portions respectively, as seen in respect of the pivot axis, positioned at respective side regions of the lever and base element. This gives increased stability to the performance of the fastener

It is also preferred that the shaft unit has a diameter that is about 2 - 5 times a thickness of material of the base element. Hereby the surface pressure in the bearing means is held at a reasonable level, i.a. allowing for the use of synthetic material.

In a preferred embodiment, there is formed a gap between the shaft unit and a remainder of the base element. This could be an upper surface of a plate portion of the base element . Said gap has a width corresponding to a thickness of material of the sleeve unit. This feature provides important guidance and control of the sleeve unit as it swings. It is also

possible to have this gap extending as an arc-shaped guiding slot around the shaft unit.

Alternatively there is formed a gap between the shaft unit and an upper surface of a lug element positioned on the base element, said gap having a width corresponding to a thickness of material of the sleeve unit.

It is preferred that the base element and the lever are produced from a respective material from the group: metal plate material, die-cast metal, formed plastic material, formed reinforced plastic material.

Preferably, the lever includes an integral axle element for pivotal support of the engagement element. This enhances the production-friendliness of the fastener as is the case when the shaft unit is supported by the remainder of the base element or the plate portion over a continuation of the plate portion having two bent portions.

The inventive fastener advantageously includes a

releasable lock mechanism for locking the lever in a tightened position.

BRIEF DESCRIPTION OF DRAWINGS

The invention will now be described in greater detail with reference to the drawings, wherein:

Figs, la and lb show an over-centre fastener according to the invention in a side view and a plane view respectively,

Fig. 2 shows, partly in section, the over-centre fastener in Figs, la and lb in the process of being assembled,

Fig. 3a shows the over-centre fastener according to the invention partly in section in an assembled state with the lever in an upwardly pivoted position, Fig. 3b shows the over-centre fastener in the position of Fig. 3a in a side view, and

Fig. 4 shows the over-centre fastener according to the invention in a tightened state partly in section in a plane view.

DESCRIPTION OF AN EMBODIMENT

In Figs, la and lb there is shown an over-centre fastener according to the invention in a side and a plane view

respectively, wherein the over-centre fastener is indicated with 1. A lever 2 is over first and second bearing means pivotally attached to a base element 3. An engagement 6 is in turn pivotally supported by the lever at a proximal portion.

The engagement element 6 has at a distal portion means for engagement with an engagement member 7. The geometry of the over-centre fastener in respect of a pivot axis 5 of a pivot joint 4 between the lever 2 and a base element 3 on the one hand and the engagement points of the engagement element 5 on the one hand on the lever 2 and on the other hand on the engagement member 7 are measure such that the usual self- locking properties of the over-centre fastener 1 is obtained.

8 indicates a lock release button for releasing a

normally active locking means, which is intended for safety purposes to lock the lever 2 in respect of the base element 3 in the position shown in Fig. la. A manipulation end 9, being a distal end of the lever 2 in respect of the pivot joint 4, is indicated with 9 and is slightly bent upwards so as to allow manipulation with a users' fingers.

15 indicates a lock aperture wherein a locking lug 13 is engaging in the locked position of the safety lock. The lock release button 8 aims to pull out the locking lug 13 from the lock aperture 15 in its release position. The pivot joint 4 comprising first and second bearing means is constructed such that integral with the base element 3 so as to form one single element together, there is a first bearing means being a shaft unit 10, which is supported by a plate portion (the linear portion of the base element 3) over a continuation of said plate portion. The continuation has two bent portions {or more general, curved portions) so as to support the shaft unit from a position directed slightly from the outside on the engagement element side of the over-centre fastener.

The second bearing means is comprised of an open sleeve unit 11 having a radial opening allowing radial introduction of the shaft unit into the sleeve unit for mutual bearing cooperation so as to form the pivot joint 4.

The shaft unit 10 is circular cylindrical, complementary to the open sleeve unit 11 which has a circular cylindrical inside corresponding to the dimensions of the shaft unit 10. Between the shaft unit 10 and an upper surface of said plate portion of the base element there is formed a gap 12 having a width corresponding to the thickness of material of the sleeve unit, which gives guidance and support for the sleeve unit during swinging and increases security of the pivot joint.

The shaft unit 10 and the sleeve unit 11 are in this embodiment comprised of axially separate shaft portions

10', 10" and sleeve portions 11", 11" (not visible in fig lb) respectively, as seen in respect of the pivot axis 5,

positioned at respective side regions of the lever 2 and base element 3.

In Fig. 2 is shown the lever 2 in a process of being assembled to the base element 3. Hereby the open sleeve unit 11 is pressed against the shaft unit 10 such that the latter will be introduced into and come into contact with the inside bearing surface of the open sleeve unit 11. 12 indicates said gap between the shaft unit 10 and the plate portion of the base element 3. A lug element 13 is positioned on said plate portion of the base element so as to form also a gap between its distal surface and the shaft unit 10, to increase control of the open sleeve unit 11 in respect of the shaft unit 10 in use of the fastener.

The lever is further provided with an integral axel element 13 at a distance from the pivot joint 4 and having a part cylindrical external surface. Said axel element 13 being intended to co-operate with a circular proximal portion 14 of the engagement element 6 so as to allow pivotal co-operation between the lever 2 and the engagement element 6. Mounting of the circular proximal portion 14 to the axel element 13 is made by pulling the engagement member outwardly for the introduction of the axel element 13 into the circular proximal portion 14.

Figs. 3a and 3b show the over-centre fastener according to the invention in assembled state and in an upwardly pivoted position of the lever 2 in respect of the base element 3. In particular in Fig. 3b, there is shown more clearly how the open sleeve unit 11 has support on the one hand in the gap 12 and on the other hand of the lug element 13.

In Fig. 4 there is shown in more detail an optional releasable lock mechanism which includes the lock release button 8. Pressing the lock release button 8 releases the locking lug element 13 from engagement with the lock aperture

15.

In particular, the elements forming the pivot joint 4 being the shaft unit and the sleeve unit respectively are comprised of axially separated shaft portions and sleeve portions respectively as seen in respect of the pivot axis. They are thereby positioned at respectively side regions of the lever and the base element, which increases stability of the device and allows for the passage between these shaft portions and sleeve portions respectively of the engagement element S, which is typically arranged centrally in respect of the lever 2.

The invention can be modified within the scope of the claims and the elements making up the over-centre fastener of the invention can be constructed otherwise. The lever 2 as well as the base element 3 can be produced from metal plate material as well as die cast metal. It is also possible and suitable to make these parts of the fastener of plastic material , which can be formed in various per se known ways . Hereby a suitable hard plastic material or fibre reinforced plastic material come into question.

The engagement element is suitably made from a metal thread material and the engagement member 7 is suitably made from a metal plate material even if other materials come into question .

The radial opening of the open sleeve unit 11 has typically cross dimensions which are slightly smaller than the diameter of the shaft unit 10 in order to provide for a holding effect between these elements in an assembled state.

Claims

CLAIMS :

1. Over-centre fastener (1) including a base element (3), a lever (2) which is pivotally attached to the base element over a pivot joint (4) having a pivot axis (5) and an engagement element (6) which, at a proximal portion (14) , is pivotally supported by the lever (2) and which, at a distal portion, has means for engagement with an engagement member (7) ,

characterized in

- that the pivot joint (4) is comprised of first bearing means being integral with the base element (3) so as to be in one piece therewith and second bearing means being integral with the lever so as to be in one piece therewith,

- that the first bearing means is comprised of a shaft unit (10) and the second bearing means is comprised of an open sleeve unit (11) having a radial opening so as to allow radial introduction of the shaft unit into the sleeve unit (11) .

2. Fastener according to claim 1, characterized in that the radial opening is measured so as to allow snap-action

introduction of the shaft unit (10) into the sleeve unit (11) .

3. Fastener according to claim 1 or 2 , characterized in that the shaft unit (10) and the sleeve unit (11) are comprised of axially separate shaft portions (10', 10") and sleeve portions (11", 11") respectively, as seen in respect of the pivot axis (5) , positioned at respective side regions of the lever (2) and base element (3) .

4. Fastener according to claim 1, 2 or 3 , characterized in that the shaft unit (10) has a diameter that is about 2 - 5 times a thickness of material of the base element (3) .

5. Fastener according to any one of the claims 1 - 4,

characterized in that there is formed a gap (12) between the shaft unit (10) and a remainder of the base element, said gap having a width corresponding to a thickness of material of the sleeve unit (11) .

6. Fastener according to any one of the claims 1 - 5,

characterized in that there is formed a gap between the shaft unit (10) and an upper surface of a lug element (13)

positioned on said plate portion of the base element (3) , said gap having a width corresponding to a thickness of material of the sleeve unit (11) .

7. Fastener according to any one of the claims 1 - 6,

characterized in that the base element (3) and the lever (2) are produced from a respective material from the group: metal plate material, die-cast metal, formed plastic material, formed reinforced plastic material.

8. Fastener according to any one of the claims 1 - 7,

characterized in that the lever (2) includes an integral axle element (13) for pivotal support of the engagement element (6) .

9. Fastener according to any one of the claims 1 - 8 in dependence of claim 5, characterized in that the shaft unit (10) is supported by the plate portion over a continuation of the plate portion having two curved or bent portions.

10. Fastener according to any one of the claims 1 - 9,

characterized in that it includes a releasable lock mechanism for locking the lever (2) in a tightened position.