Tensioning Buckle

This invention relates to buckle type fittings capable of locking belt in load bearing situations.

In many situations there is a need to be able to achieve a high degree of tension in a belt, maintain the tension securely and quickly release it when desired.

While existing buckle fittings may be capable of some or all of these functions, they usually involve complicated construction and fallible ratchet and spool mechanisms. The need is recognised to produce a tensioning buckle of lightweight, slim design with a simple construction and operation as well as being capable of the mentioned functions.

An object of the present invention is to provide a simple buckle fitting that can apply, maintain and instantly release tension in lengths of belt.

Another object is to provide a buckle that is in principle applicable to all sizes of belt.

Another object is to provide a buckle fitting that can effectively lock at any point along the length of an unperforated belt without distorting or winding the excess belt onto a spool mechanism.

Another object is to provide a buckle fitting as described, of simple construction and operation, light weight, thin dimension and having few parts.

In general summary the buckle includes two u-sectioned bodies pivotably connected at one end. The lower body houses a spring loaded cam which allows belt to advance through the buckle but prevents the belt slipping back. A roller also located in the lower body facilitates the belt movement and reduces friction. The longer upper body contains a tongue and slot which, when levered about the pivot attachment to the lower body will grip and pull belt further through the cam. Repeating this lever action advances and maintains tension in the belt until released via the cam mechanism.

FIG. 1 is a sectioned elevation of one embodiment of the invention.

FIG. 2 is a plan view of the invention.

FIG. 3 is a perspective illustration of the invention.

The drawings depict a tensioning buckle comprising a u-sectioned lower body 1, being pivotably connected at hinge pivots 3,4 to a similarly sectioned slightly wider, upper body 2. Upper body 2 may thus close over lower body 1 and pivot freely, up to 180 degrees, about lower body 1 at hinge pivots 3,4.

Protruding edges of cam 5 locate laterally in lower body 1 by seating in holes 6,7. Holes 6,7 are suitably shaped to allow a limited turning action of cam 5 about a line through holes 6,7. The turning action of cam 5 effectively raises and lowers the belt contact edge 5b relative to the surface of lower body 1 while the opposite relative movement occurs at finger contact end 5a. Means to apply pressure tending cam belt contact edge 5b towards lower body 1 is achieved by torsion spring 8. A medial portion of torsion spring 8 contacts cam 5 while the ends locate in tabs 9,10 in lower body 1.

A cylindrical roller 11 locates laterally in lower body 1 between cam 5 and hinge pivots 3,4. Round holes 12,13 locate roller 11 in lower body 1 so as to allow turning and enable belt 16 to pass between.

The surface of lower body 1, between the roller 11 and and hinge pivots 3,4 protrudes upwards to form a tongue 14, which correlates to a similar tongue 15 projecting down from upper body 2. When upper body 2 is positioned to overlap lower body 1, tongues 14 and 15 converge to provide means to direct belt 16 through a slot 17 in upper body 2.

Means to attach one end of belt 16 to lower body 1 is provided by studs 18 passing through holes in plate 19, belt 16 and lower body 1.

The end of upper body 2 extending furthest from hinge pivots 3,4 is upturned at grip 2a to facilitate manual lifting and levering of upper body 2 about lower body 1.

In the use and operation of the invention; belt 16 is passed around objects to be restrained and the free end of belt 16 is passed along the upper surface of lower body 1, between cam 5 and roller 11. With upper body 2 closed over lower body 1, belt 16 is guided by tongue 14 onto tongue 15 and through slot 17. Upper body 2 is then manually levered about hinge pivots 3,4 on lower body 1. As the aspect of slot 17 alters, belt 16 is gripped and pulled further along the surface of lower body 1, between the roller 11 and cam belt contact edge 5b. After the lever arc of upper body 2 is completed it is returned to seat over lower body 1, while cam 5 prevents belt 16 as belt contact edge 5b locks into belt 16 and against lower body 1. Repeating the lever action further advances belt 16 through the buckle until the desired tension is achieved. Upper body 2 is then returned to cover lower body 1 thus preventing accidental release of the cam 5. To release belt 16, upper body 2 is levered about lower body 1 allowing recess to cam finger contact end 5a. Depressing cam 5 at finger contact end 5a raises the belt contact edge 5b from the surface of the belt 16 thus releasing it.

The above description details an embodiment of the invention thats true spirit and scope are embraced in the following claims;