Oct. 29, 1968 D. N. DEWEY ET AL I 3,407,451
LOW PROFILE REVERSIBLE THREE-BAR ADJUSTABLE STRAP CONNECTOR Filed June 20, 1966 I0 fie. 4'
INVENTORS DWIGHT N. DEWEY BY JOHN STACHERL' ZM .Z% JWM#: W
' ATTORNEYS United States Patent 3,407,451 LOW PROFILE REVERSIBLE THREE-BAR ADJUSTABLE STRAP CONNECTOR Dwight N. Dewey, West Hartford, and John Stacheri, New
Britain, Conn., assignors to The Capeweil Manufacturing Company, Hartford, Conn., a corporation of Connecticut Filed June 20, 1966, Ser. No. 558,909
4 Claims. (Cl. 24-196) ABSTRACT OF THE DISCLOSURE A low profile reversible three-bar quick fit adjustable strap connector is provided with a rockable gripping bar around which a strap is threaded to provide an offset force securing the free end of the strap in adjusted pos1t1on. A channel-shaped tensioner having ends which straddle s de rails of the connector and includes a bowed leaf spring biasing the tensioner into engagement with a gripping bar prevents the loosening of the strap when little or no tension is applied to the strap. The channel-shaped tensioner is provided with divergent walls to permit it to t lt slightly and apply an offset biasing force against the gripping bar to cause it to pinch the strap against an end bar of the connector. The divergent walls of the tensioner enable it to apply and offset biasing force on the gripping bar regardless of the reversal of the threading of the strap around the gripping bar and the bowed spring nested in the tensioner may have a low spring rate to permit the easy threading and adjustment of the strap around the gripping bar while preventing inadvertent loosening.
This invention relates to strap connectors and more particularly to a low profile reversible, quick-fit three-bar adjustable strap connector, having particular utility for adapting or fitting parachute harnesses or the like to different users.
One of the objects of this present invention is to provide an improved reversible, adjustable, quick-fit, low profile three-bar strap connector of the aforedescribed type that will effectively clamp the free end of a strap although the strap is subjected to a relatively great load and which, when the load is lessened or removed, will maintain the free end of the strap in the desired adjusted position.
A further object of the present invention is to provide an adjusting linkage for harness webbing, including a reversible three-bar strap connector incorporating a novel webbing tensioner that will effectively secure the free end of a strap in its adjusted position when the strap is not under heavy load while at the same time permitting the strap portion to be easily and rapidly adjusted. Included in this object is the provision of a low profile adjusting linkage having minimum susceptibility to inadvertent adjustment.
Other objects will be in part obvious and in part pointed out more in detail hereinafter.
The invention accordingly consists in the features of construction, combination of elements and arrangement of parts which will be exemplified in the construction hereafter set forth and the scope of the application of which will be indicated in the appended claims.
In the drawings:
FIG. 1 is a top plan view of an adjusting linkage for harness webbing embodying the present invention;
FIG. 2 is an exploded view of the webbing tensioner utilized in the practice of this invention prior to assembly in the strap connector incorporated in FIG. 1;
FIG. 3 is a fragmentary perspective view of the tensioner of FIG. 1;
FIG. 4 is an enlarged cross-sectional view taken generally along lines 44 of FIG. 1 when the straps are under tension; and
FIG. 5 is a cross-sectional view generally similar to that of FIG. 3 but taken when one of the straps is inverted.
Referring to the drawings in detail, the illustrative strap adjusting linkage embodying the present invention includes straps 10 and 12, strap 10 being fixedly secured to an end bar 13 of a three bar connector 14 and strap 12 being adjustably secured to the connector. The strap connector 14 includes a forged steel frame comprising parallel side rails 16, 18 and transversely disposed integral bars 20, 22 which define a generally rectangular opening 24. A gripping cross bar 26 is supported on the side rails 16, 18 for sliding and limited rocking movement by means of the bifurcated end projections 28 which loosely straddle the side rails 16, 18.
As shown in FIG. 1, the end bar 13 receives the looped end of the strap or webbing 14) which is stitched as indicated at 11 or otherwise secured in permanent fashion to fixedly embrace the end bar 13 within its loop.
The other strap 12 is adapted to be adjustably received by the frame by threading the free end 12a around the gripping bar 26, between the gripping bar and the transverse end bar 20 and then outwardly of the frame, FIG. 1 showing one method of threading the strap 12 wherein the free end 12a is initially inserted into the opening 24 from the lower side thereof. The end bar 20 and gripping bar 26 are provided with a complementary tongue 30 and groove 52, respectively, which are cooperable to clamp the free end 12a of the strap 12, as shown in FIG. 4, when tension is applied to the strap 12 causing the gripping bar 26 to slide and limitedly rock relative to the side rails 16, 18.
In many connectors of the aforedescribed type, when the strap 12 is in a relatively relaxed and unclamped state such as when no load is applied thereto, the free end 12a may move from its adjusted position due to vibrations imposed thereon.
In accordance with this invention, a novel webbing tensioner is provided which uniquely obviates the above problem without impairing the normal operation of the connector 14 or the adjustability of the strap 12.
In the illustrated embodiment, the webbing tensioner 34 comprises a generally channel-shaped body, formed from sheet material such as stainless steel or the like, which is positioned in the gap 36 formed between the transverse bar 22 and the gripping bar 26. The tensioner 34 is closely received between side rails 16, 18 and includes first and second fiat side walls 38, 40, the ends of which loosely overlie and straddle the side rails 16, 18 to support the tensioner 34 for sliding and limited rocking movement relative thereto. A bottom wall 42 bridges the side walls 33, 40 to hold the tensioner 34 in nestling relationship with intermediate transverse bar 22. Since a strap member is not threaded around transverse bar 22 of the connector, the tensioner 34 does not wedge or bind therewith and is free to slide on the side members 16, 18 of the connector 14 under the influence of a very low biasing force.
As shown in FIG. 4, the side walls 38, 40 diverge from bottom wall 42 and have an included angle of about 10. A bowed leaf spring 44 interposed between the tensioner 34 and transverse bar 22 exerts a biasing force lightly urging tensioner 34 (and gripping bar 26) to the right, as viewed in FIG. 4, when little or no tension is applied to straps 10, 12. As shown in FIG. 4, bottom wall 42 engages free end 12a of strap 12 along a transverse line which is offset or below the plane of the connector 14 Whichpasses through the centers of the transverse bars 20, 22 to cause the gripping bar 26 to tilt slightly to increase the effectiveness of the clamping action on strap 12.
To assemble, the tensioner 34 in which leaf spring 44 is nested is inserted in the gap 36 between transverse bar 22 and gripping bar 26 until the end projections of the side wall 40 rest against side rails 16, 18 of connector 14. This is accomplished by virtue of a bent up end projection 38a of wall 38 which allows the insertion of the tensioner between side members 16, 18 of the frame. After insertion, end projection 38a is bent downward into the plane of side wall 38 and the free end 12a of strap 12 is threaded around gripping bar 26 as shown in FIG. 4. A V-shaped notch 39 having a rounded apex is provided to avoid the concentration of stresses and fracture as the end 38a is bent out of and into the plane of side wall 38 for assembly.
With the tensioner 34 assembled in place in the connector 14, the bottom wall 42 of the tensioner will sufficiently force the strap 12 against the gripper bar 26 to produce a clamping effect between gripping bar 26 and end bar 20, as shown in FIG. 4, which will prevent slippage of the strap 12 relative to the gripping bar 26 when the strap 12 is not under tension. Although the tensioner 34 will eifectively prevent inadvertent slippage of the strap portion 12a relative to the gripping bar 26, the low spring rate of the biasing spring 44 will readily permit the strap 12 to be manually adjusted.
When the straps 10, 12 are under tension, the gripping bar 26 will rock slightly due to the loose fit between the bifurcated ends 28 of the gripping bar and the side rails 16 and 18 and slide toward the end member 20 to securely clamp the strap 12 therebetween. By virtue of the use of a three-bar construction, the strap connector 14 provides a low profile or silhouette with the transverse end bar 20 being positioned closely adjacent to strap 12 and sheltered against accidental contact when the connector is used for providing an adjustable parachute harness. This reduces the possibility of loosening of the harness through an accidental sore-thumb engagement of the connector in use. Moreover, the line of pull between straps and 12 falls along closely adjacent paths by virtue of the three-bar construction and as a result the end bar 13 does not protrude toward the body of the user to concentrate the impact forces on a small area of the users body under the shock of parachute opening.
FIG. 5, which is similar to FIG. 4, illustrates the reversibility of the strap connector. As illustrated in FIG. 5, the strap 12 is threaded around the gripping bar 26 in the reverse direction from that shown in FIG. 4. In actual practice, this would normally occur when the strap 10 sewn to the end bar 13 is twisted a half turn without the knowledge of the user. Under such a circumstance, the user would thread the strap 12 around the gripping bar 26 in what he believed to be the usual manner with the strap 12 near his body and the free end 12a of the strap overlying the major portion of strap 12. However, since the connector 14 is inverted due to the half twist in the strap 10, the user would actually be threading the strap 12 around the gripping bar 26 in the reverse direction. Due to the symmetry of the tensioner 34, it is still effective to maintain the tension on the strap 12 despite the reversal in the orientation of the strap 12 relative to the gripping bar 26.
From the foregoing, it will be apparent that this invention provides an adjusting linkage for harness webbing incorporating a three-bar strap connector having a low profile and incorporating a novel webbing tensioner which is effective even though the adjustable strap is threaded through the connector in the intended or the reverse direction. It is further apparent that the tensioner may utilize a biasing spring having a low spring rate since the side walls 38, 40 do not engage the straps or webbing.
As will be apparent to persons skilled in the art, various modifications and adaptations of the structure above described will become readily apparent without departure from the spirit and scope of the invention, the scope of which is defined in the appended claims.
1. A low profile adjusting linkage for harness webbing and the like including a reversible three-bar strap connector having a pair of parallel side rails connected by three parallel transverse bars, a first strap fixedly secured to an end one of said transverse bars and a relatively slidable and rockable gripping bar disposed between the other two transverse bars for receiving the free end of a second strap threaded around said gripping bar and between the gripping bar and the other end bar, a channelshaped tensioner having side walls providing end projections straddling the side rails of the connector and con-' nected by a bottom wall, said tensioner side walls diverging from said bottom wall and assembled in nesting relation with the intermediate transvers bar of the connector, and a biasing spring interposed between said intermediate transverse bar and said bottom wall of the tensioner for biasing the tensioner toward said gripping bar to provide a tensioner effective to maintain the adjustment of the strap members when the straps are not under tension and regardless of the forward or reverse threading of the adjustable strap member around the gripping member.
2. A linkage as recited in claim 1 wherein the biasing spring is a bowed leaf spring nested between the tensioner and the intermediate transverse bar of the connector.
3. A device as recited in claim 1 wherein a V-shaped notch having a rounded apex is provided at the inner section of the bottom wall of the tensioner and one of the end projections of a side wall thereof to prevent the fracture thereof when said end projection is bent during the assembly of the tensioner with the connector.
4. A device as recited in claim 1 wherein the included angle between the diverging side walls of the connector is about 10.
References Cited UNITED STATES PATENTS 2,938,254 5/1960 Gaylord 24--l7l 3,293,713 12/1966 Gaylord 24-196 BOBBY R. GAY, Primary Examiner.
E. SIMONSEN, Assistant Examiner.