WO1991016832A1

WO1991016832A1 - A strap-tensioning buckle

Info

Publication number: WO1991016832A1
Application number: PCT/GB1991/000729
Authority: WO
Inventors: Peter Rodgers; Eric Charles Beard
Original assignee: Drazil, Jaromir, Vaclav
Priority date: 1990-05-10
Filing date: 1991-05-08
Publication date: 1991-11-14
Also published as: AU7791791A

Abstract

The buckle comprises a base member (1) to which are pivotally connected a strap-tensioning member (11) displaceable between a strap-tensioning position and a strap-releasing position and a locking handle member (21) displaceable between a locking position and a releasing position. All the three members are made of plastics. The strap-tensioning member is provided with a transversely extending recessed portion (17) and the locking handle member is provided with a nose portion (24) engageable in the recessed portion when the locking member is in its locking position and the strap-tensioning member is in its strap-tensioning position to lock the strap-tensioning member in that position. Resilient means (28; 29) are provided for urging the locking handle member to its locking position.

Description

A STRAP-TENSIONING BUCKLE Technical Field

The invention relates to a strap-tensioning buckle, particularly a buckle suitable for restraining load on, lorries or the curtain on curtain-sided lorries. Background Art

A number of embodiments of strap-tensioning buckles are known. The known buckles have various disadvantages, known to persons skilled in the art. The aim of the present invention is to avoid these disadvantages by producing a buckle which represents an improvement over known buckles, mainly in that it is made of plastics and consequently is cheap and non-corroding, and is reliable and easy to operate. Disclosure of Invention

The invention provides a strap-tensioning buckle comprising a base member to which are pivotally connected a strap-tensioning member displaceable between a strap- tensioning and a strap-releasing position and a locking handle member displaceable between a locking position and a releasing position, wherein all the three members are made of plastics, the strap-tensioning member is provided with a recessed portion and the locking handle member is provided with a nose portion engageable in the said recessed portion when the locking member is in its locking position and the strap-tensioning member is in its strap-tensioning position to lock the strap- tensioning member in that position, resilient means being provided for urging the locking handle member to its locking position.

Brief Description of Drawings

The invention will now be described, by way of example, with reference to the accompanying diagrammatic drawings, in which: Figure 1 is a perspective view of a first embodiment of a buckle without a strap in closed state,

Figure 2 is a side elevation of the first embodiment of a buckle, partly in section, without a strap in closed (and partly open) state, ^" Figure 3 is a diagrammatic illustration of the strap path,

Figure 4 is a plan, partly in section, of a preferred second embodiment of a buckle in closed state, and Figure 5 is a section along line V-V in Figure 4.

Modes of Carrying Out the Invention

The buckle according to both the embodiments comprises three main parts, namely a base member 1, a strap-tensioning member 11 and a locking handle member 21. All the three members are made of plastics.

Whenever the first end portion of any of these members or their parts is mentioned it is the left-hand portion and whenever the second end portion is mentioned it is the right-hand end portion in the drawings. The base member 1 is formed by two substantially identical, spaced-apart and parallel side walls 2 interconnected by a base extending substantially perpendicularly thereto.

In the illustrated example the base is formed by three spaced-apart transverse base elements, namely a first base element 3 situated at the first end portion and provided with two spaced-apart circular holes 7, a third base element 3C situated at the second end portion and a second base element 3B situated between the first and a third base elements. The three base elements define between them two spaced-apart, substantially rectangular windows 4 and 5. The windows 4 and 5 are preferred but could be dispensed with.

In the first end portions of the side walls 2 are provided stop surfaces 6, mutually coaxial first circular holes 2A and mutually coaxial second circular holes 2B and in the second end portions mutually coaxial TIR holes 2C and mutually coaxial third circular holes 2D. The stop surfaces 6 serve to define the fully open position of the strap-tensioning member 11. In order to brake the member 11 before it hits the stop surfaces the inner surface of the adjacent portions of the side walls 2 are made to slightly converge.

The strap-tensioning member 11 is formed by two substantially identical spaced apart and parallel side walls 12, which are free at the first end portion of the member 11 but are interconnected at the second end portion by a first planar element 13 and by a second planar element 14, spaced from the latter so as to provide a gap 14A. The elements 13 and 14 extend substantially perpendicularly to the side walls 12 and have straight transverse edges. The edge of the element 14 delimiting the gap 14A is rounded.

At their first end portions the side walls 12 of the strap-tensioning member 11 are provided with mutually coaxial, circular holes 12A and at the second end portions with mutually coaxial TIR holes 12B. The side walls 12 extend at their first end portions between the side walls 2 and are to the latter pivotally connected by a pivot 15, in the illustrated example a metal pin which passes through the holes 12A, is received in the holes 2B and carries a freely rotatable roller 15a.

The second end portion of the strap-tensioning portion 11 is provided with a transversely extending end wall 16 which is substantially perpendicular to the side walls 12 and to the element 13. The end wall 16 is formed to provide a groove 17 delimited by a first flank element 18 and a second flank element 19. The outer edge of the second flank element 19 is curved. The locking handle member 21 is delimited by a curved upper wall 23 formed at its second end portion into a gripping portion and at its first end portion into a transverse nose portion 24, and by two side walls 25 provided with mutually coaxial circular holes 26. The first end portion of the locking handle member 21 is situated between the side walls 2 at their second end portion and is pivotally connected to the base member 1 by a pivot 27, in the illustrated example a metal pin which passes through the holes 2D and 26. The strap-tensioning member 11 is displaceable between a closed position and an open position. The closed position is a strap-tensioning position shown in solid lines in Figures 1, 2, 4 and 5, and the open position is a strap-releasing position, which may be a partially open position, e.g. that shown in chain-dotted lines in Figure 2, but usually is a fully open position in which the member 11 rests on the stop surfaces 6. The locking handle member 21 is displaceable between a locking position and a releasing position. In the locking position the nose portion 24 of the member 21 is received in the groove 17 (or other recessed portion) of the member 11 when the latter is in the closed position and is in contact with the second flank element 19. In the releasing position the nose portion 24 is moved out of contact with the second flank element 19, whereby the member 11 is released and pulled by the tension of the strap to an open position. As explained below, biasing means are provided for biasing the member 21 to its locking position so that this position is assumed by this member even if the member 11 is in its open position.

The operational position of the buckle is a position in which the member 11 is locked in its closed position by the member 21 is in its locking position in which its nose portion 24 engages with the second flank element 19 of the member 11. In this position the TIR holes 2C and 12B are aligned so that a TIR cable can be threaded through them.

In the first embodiment shown in Figures 1 and 2 the locking handle member 21 is substantially solid and has at its first end portion a chamber 22 accommodating the biasing means in the form of a wire spring 28 which is in the form of a helix with two outwardly diverging legs and is carried on the pivot pin 27. One of the legs of the spring 28 bears from inside on the curved wall 23 and the other extends outside the chamber 22 and bears on the third base element. This causes the locking handle member 21 to be biased to its locking position shown in Figures 1 and 2. The second embodiment shown in Figures 4 and 5 has a substantially hollow locking handle member 21 comprising a curved upper wall 23, formed at its first end portion into a transverse nose portion 24, and two side walls 25 provided with holes as described in connection with the first embodiment. The second embodiment has, instead of the wire spring 28, fingers 29 projecting from the locking handle member 21, in the illustrated embodiment two laterally situated, spaced apart, curved fingers 29 which are integral with the handle member 21 and form the biasing means. The front ends of the fingers 29 bear on to narrow lateral ledges extending along and at an angle to the side walls 2. The ledges and fingers may be shaped or provided with interengageable elements, such as recesses and projections, to avoid slipping of the fingers 29 from the ledges. The fingers 29 cause the handle member 21 to be biased to its locking position shown in Figure 5. In the second embodiment spaced-apart strap guides 30 are provided on the third base element 3C. For the opening of the buckle, the gripping portion of the locking handle member 21 is lifted, i.e. the member 21 is displaced from its locking position to its releasing position, whereby the nose portion 24 is withdrawn from the groove 17 so that the strap-tensioning member 11 is by the strap lifted to its open position.

For the threading of the strap in the buckle, the buckle is fully opened i.e. the strap-tensioning member 11 is pivoted anti-clockwise (in Figure 2) and the free end of the strap is inserted from the second end portion of the buckle above the base element 3C through the window 5 and below the second base element 3B, up through the window 4 and below the pivot 15, is then guided around the rounded edge of the member 14 and again above the pivot member 15 and out of the second end portion of the buckle.

In use the strap-tensioning member 11 is lifted to the fully open position, and the operator then manually tightens the strap by pulling at its free end until a satisfactory tightening is achieved, whereupon he pivots the member 11 from the open position clockwise until the curved outer edge of the second flank element 19 contacts the curved wall 23 and further movement of the strap-tensioning member 11 turns the handle member 21 anti-clockwise about the pivot 27 which deflects the nose portion 24 until it can finally pass the second flank element 19 and enter the groove 17 under the influence of the spring 28 or of the fingers 29 whereby the member 11 is locked in its closed position by the member 21 which is in its locking position. It will be apparent that the groove 17 is much wider than is needed for the width of the nose portion 24 to allow for a certain play in the movement of the strap-tensioning member 11. During the clockwise movement the strap is further tightened by the member 14. It will be understood that the drawings show only two preferred embodiments which can be modified in various respects within the scope of the claims .

Claims

1. A strap-tensioning buckle comprising a base member (1) to which are pivotally connected a strap- tensioning member (11) displaceable between a strap- tensioning position and a strap-releasing position and a locking handle member (21) displaceable between a locking position and a releasing position, characterised in that all the three members are made of plastics, the strap- tensioning member being provided with a recessed portion (17) and the locking handle member being provided with a nose portion (24) engageable in the said recessed portion when the locking member is in its locking position and the strap-tensioning member is in its strap-tensioning position to lock the strap-tensioning member in that position, resilient means (28;29) being provided for urging the locking handle member to its locking position.

2. A buckle according to Claim 1 wherein the locking handle member is extended to provide the resilient means.

3. A buckle according to Claim 2 wherein the resilient means are formed by two spaced-apart fingers (29).

4. A buckle according to Claim 3 wherein the fingers are laterally situated curved fingers integral with the locking handle member and the base member is provided with ledges for supporting the fingers.

5. A buckle according to any one of Claims l to 4 wherein the base member is provided with stops (6) and braking means for the strap-tensioning member.

6. A buckle according to any one of Claims l to 5 wherein the base member is provided with spaced-apart strap guides.