WO2021229326A1

WO2021229326A1 - Safety harness with strap adjuster

Info

Publication number: WO2021229326A1
Application number: PCT/IB2021/053292
Authority: WO
Inventors: Stephen D. SHAVER
Original assignee: 3M Innovative Properties Company
Priority date: 2020-05-12
Filing date: 2021-04-21
Publication date: 2021-11-18
Also published as: TW202208027A

Abstract

A fall-protection safety harness with a directional strap adjuster to which is adjustably connected a first strap of the harness. The strap adjuster includes a first main body having an upper, clamping end and a lower, attachment end, and a second main body having an upper, clamping end and a lower, attachment end, the first main body and the second main body being pivotally connected to each other by a pivotal connection.

Description

SAFETY HARNESS WITH STRAP ADJUSTER

Background

Safety harnesses are often used to reduce the likelihood of a user experiencing a fall, and/or to safely arrest the user in the event of a fall. Such harnesses are often used in combination with one or more of a self-retracting lifeline (e.g., a personal self-retracting lifeline), an energy-absorbing lanyard, and other fall-protection equipment.

Summary

In broad summary, herein is disclosed a fall-protection safety harness with a directional strap adjuster to which is adjustably connected a first strap of the harness. The strap adjuster includes a first main body having an upper, clamping end and a lower, attachment end, and a second main body having an upper, clamping end and a lower, attachment end, the first main body and the second main body being pivotally connected to each other by a pivotal connection. These and other aspects will be apparent from the detailed description below. In no event, however, should this broad summary be construed to limit the claimable subject matter, whether such subject matter is presented in claims in the application as initially filed or in claims that are amended or otherwise presented in prosecution.

Brief Description of the Drawings

Fig. 1 is a rear view in generic representation of an exemplary fall-protection safety harness equipped with exemplary strap adjusters as disclosed herein.

Fig. 2 is a front view in generic representation of an exemplary fall-protection safety harness equipped with exemplary strap adjusters, as worn by a user.

Fig. 3 is an isolated magnified front view of an exemplary strap adjuster and straps associated therewith.

Fig. 4 is a side-front view of an exemplary strap adjuster.

Fig. 5 is a side-rear view of the exemplary strap adjuster of Fig. 4.

Fig. 6 is a side-rear exploded view of the exemplary strap adjuster of Figs. 4 and 5, showing a forward clamping member of the strap adjuster and a rearward clamping member of the strap adjuster exploded apart from each other.

Fig. 7 is a conceptual side view of an exemplary strap adjuster showing straps associated with the strap adjuster and depicting how various forces may act on the adjuster and straps.

Like reference numbers in the various figures indicate like elements. Some elements may be present in identical or equivalent multiples; in such cases only one or more representative elements may be designated by a reference number but it will be understood that such reference numbers apply to all such identical elements. Unless otherwise indicated, all figures and drawings in this document are not to scale and are chosen for the purpose of illustrating different embodiments of the invention. In particular the dimensions of the various components are depicted in illustrative terms only, and no relationship between the dimensions of the various components should be inferred from the drawings, unless so indicated. Although terms such as “first” and “second” may be used in this disclosure, it should be understood that those terms are used in their relative sense only unless otherwise noted. As used herein as a modifier to a property or attribute, the term “generally”, unless otherwise specifically defined, means that the property or attribute would be readily recognizable by a person of ordinary skill but without requiring a high degree of approximation.

The following terminology is defined with respect to a fall-protection safety harness as worn by a user standing upright, when viewed from behind the user. It is emphasized that this terminology is used for clarity of description and does not limit the actual orientation of the harness and components thereof, during actual use. Terms such as vertical, upward and downward, upper, lower, above, and below, and like terminology, correspond to conventional directions with respect to the Earth when the harness is worn by a user who is standing upright. The upward (u) and downward (d) directions along the vertical axis are denoted in Fig. 1. The term forward denotes a direction that is generally perpendicular to the vertical axis and is away from the body (specifically the chest area) of a user of the harness. The term rearward denotes a generally opposing direction, toward the body (e.g. chest) of the user of the harness. Left and right directions are from the point of view of a wearer of the harness, as will be evident from inspection of Figs. 1 and 2.

Detailed Description

Fall-protection safety harnesses, some-times referred to as full-body safety harnesses, are widely used in circumstances in which workers are at elevated height or are otherwise at risk of falling. A fall-protection safety harness is configured to serve in combination with a fall-protection device or apparatus such as, e.g., a self-retracting lifeline or horizontal lifeline, a lanyard or the like, to provide fall protection. Thus in ordinary use, at least one such fall-protection device is typically connected to the safety harness, e.g., to a D-ring (or other suitable connection point) borne by the harness. Fall- protection safety harnesses will be distinguished from, for example, general-use items such as backpacks and the like.

As illustrated in generic representation in Figs. 1 and 2, a fall-protection safety harness 1 will comprise an assembly of various straps that can collectively support the weight of a wearer of the harness in the event of a fall. The particular arrangements of Figs. 1 and 2 are intended as exemplary representations; in actuality a safety harness may vary from the arrangements shown in these Figures. Also, the exemplary harnesses of Figs. 1 and 2 differ in various ways and are not to be interpreted as different views of the same harness.

The straps of such a harness are often comprised of flat webbing, made of, e.g., woven synthetic fabric such as, e.g., polyamide, polyaramid (such as, e.g., Kevlar), ultra-high molecular weight polyethylene (such as, e.g., Dyneema) and the like. Such straps are typically flexible so that they can conform to the surface of a wearer’s body, can be passed through one or more of buckles, guides, loops and the like, but typically are not significantly extensible. Such straps are interconnected with each other and are often fitted with various pads (e.g., shoulder pads 4 and waist/hip pad 8) to enhance the comfort of the harness, as well as various buckles, latches, connectors, loops, guides, additional pads such as, e.g., chest pads and/or leg pads, and so on. Such components and exemplary arrangements of such components are described in, for example, U.S. Patents 8959664, 9174073, and 10137322, all of which are incorporated by reference in their entirety herein.

A safety harness 1 typically includes first and second (left and right) shoulder straps 2 and 3 that extend over the top of the shoulders as shown in Fig. 2. On the front side of the wearer, left and right shoulder straps 2 and 3 continue generally downward along the upper portion of the wearer’s torso as seen in Fig. 2; at such locations they will be referred to herein as chest straps (noting that each chest strap is often an uninterrupted continuation of a shoulder strap, as evident from Figs. 1 and 2).

In many embodiments, at some point along the wearer’s frontal torso, first and second chest straps 2 and 3 will respectively meet first and second (left and right) strap adjusters 100 as shown in Figs. 1 and 2. Below each strap adjuster 100, a strap (left and right straps 12 and 13, in Figs. 1 and 2) will extend generally downward to meet (and to e.g. interconnect with) a strap 5 (which may be termed a waist strap, hip strap, etc.) that encircles at least a portion of the waist/hip area of the user. For convenience of description, straps 12 and 13 that are below strap adjusters 100 will be referred to as abdominal straps to distinguish them from chest straps 2 and 3 which are above strap adjusters 100.

In the arrangements disclosed herein, a chest strap (e.g. 2) that is connected to an upper end of a strap adjuster 100 will be a physically different strap from an abdominal strap (e.g. 12) that is connected to a lower end of the same strap adjuster 100. (In other words, an abdominal strap (e.g. 12) is not an uninterrupted continuation of a chest strap (e.g. 2) in the way that a chest strap is often an uninterrupted continuation of a shoulder strap.) A strap adjuster 100 as disclosed herein is thus connected to two different straps and can be used to adjust the length of one of the two straps as will be made clear by the detailed discussions herein. Such a strap adjustor is thus distinguished from an adjuster that is mounted on a single, continuous strap that extends continuously through the adjuster and which serves to adjust the length of the single continuous strap. Moreover, a strap adjuster 100 as disclosed herein is made of parts that are configured to not be disconnectable from each other in ordinary use of the strap adjuster. That is, no part of the strap adjuster will be disconnectable from any other part of the strap adjuster. A strap adjuster 100 as disclosed herein thus differs from, e.g., buckles that have portions that are fastened together and separated from each other, multiple times, in ordinary use. A strap adjuster as disclosed herein is thus distinguished from such buckles.

In many embodiments one strap or both straps that are connected to such a strap adjuster 100 are non-detachably connected to the strap adjuster. By non-detachably is meant that the strap cannot be disconnected from the strap adjuster without unacceptably damaging, or destroying the strap and/or the strap adjuster. For example, in some embodiments a torso strap may be non-detachably connected to a strap adjuster e.g. by being passed through one or more slots of the strap adjuster and then turned back on itself and sewn to itself to form a terminal loop that is captured in the one or more slots, as discussed later in detail.

In some embodiments, harness 1 will also include leg or thigh straps (shown, unnumbered, in Figs. 1 and 2); in some embodiments such straps may be a continuation of abdominal straps 12 and 13. In many safety harness designs, first and second shoulder straps 2 and 3, on the rear side of the wearer’s torso, will meet, overlap and cross each other at a dorsal crossing point. Often a dorsal D-ring 40 is provided at such a location as shown in Fig. 1. (D-rings may also provided at other locations, as evident in the exemplary design of Fig. 1.) A fall-protection safety harness may also include one or more plates (e.g. a dorsal plate) that may be relatively rigid (e.g., made of molded plastic and/or metal) in comparison to other, relatively flexible harness components such as pads and cushions. In some embodiments a harness may include a chest-strap coupler 9 which, as evident from Figs. 1 and 2, is a short, generally horizontally-extending strap that can couple left and right chest straps 2 and 3 to each other to further stabilize the harness.

Strap adjuster

A fall-protection harness 1 as disclosed herein comprises at least one strap adjuster 100. Strap adjusters 100 are shown in Figs. 1 and 2 as being positioned on the wearer’s chest and being configured to adjust the length of a chest strap 2 or 3. However, such a strap adjuster may be positioned and configured to adjust the length of any desired strap, whether it is e.g. a chest strap, an abdominal strap, a waist or hip strap, a leg strap, a chest-strap coupler, etc. Strap adjuster 100 is merely described herein in the exemplary context of serving to adjust a chest strap. Accordingly, terms such as up, down, upper, lower, and so on, are used to describe the strap adjuster as conventionally positioned proximate the wearer’s frontal torso and as used to adjust the length of a chest strap that approaches the strap adjuster from above. However, this terminology is purely for ease of description; those of ordinary skill in the art of harness design will straightforwardly be able to adapt such descriptions for embodiments in which the strap adjuster of this disclosure is used to adjust the length of some other harness strap.

It is emphasized that a strap adjuster as disclosed herein is configured specifically for use in a fall-protection safety harness, and will be used for the specific purpose of adjusting the length of a strap such a harness. Such a strap adjuster will thus be distinguished from, for example, a device that may be used to support the weight only of some relatively lightweight ancillary item (e.g. a hard hat, safety glasses, etc.) rather than serving as a component of a fall-protection safety harness that must support the full weight of a user in the event of a user fall. A strap adjuster as disclosed herein is thus distinguished from e.g. a “tether clip” of the general type disclosed e.g. in U.S. Patent Application Publication No. 2020-0124066. In some embodiments, a strap adjuster as disclosed herein (as well as the harness in which it is installed) may meet the requirements of ANSI Z359.12 and CSA Z259.12 (Connecting Components for Personal Fall Arrest Systems).

As shown in exemplary embodiment in the isolated magnified view of Fig. 3, a strap adjuster is configured to have first and second straps (chest strap 2 and abdominal strap 12, in the exemplary depiction of Fig. 3) connected thereto. In the illustrated embodiment, second strap 12 is non-detachably connected (i.e., is attached) to a lower end 154 of strap adjuster 100. This can be achieved e.g. by passing an end section of strap 12 through at least one slot in the lower end of the strap adjuster, turning this end section of strap 12 back on a section of strap 12 that is downward from strap adjuster 100, and then sewing, stitching, or otherwise attaching the strap end to the downward section to form a terminal loop 14 that is captured in the slot of the strap adjuster as indicated in Fig. 3. (Further details of such arrangements are discussed later herein.) Such attachment will typically be at the factory where the harness is made and where the strap adjuster is installed in the harness such a strap will typically remain attached to the strap adjuster 100 at all times during ordinary use and care of the harness.

First strap 2 is adjustably connected to upper end 153 of strap adjuster 100. In some embodiments, this can be done by passing a free end 2_f of strap 2 through at least one slot in the upper end 153 of the strap adjuster, turning the terminal end of free end 2_f back on a penultimate section of free end 2_f, and then sewing, stitching, or otherwise attaching the strap-end to itself to form a terminal loop 15. Terminal loop 15 differs from loop 14 in that loop 15 is not captured in a slot of the strap adjuster. Rather, terminal loop 15 merely serves to provide a bulky feature so that, once the bulky feature is in place, the free end 2_f of strap 2 is not able to pass through the slot through which strap 2 extends.

In such an arrangement, free end 2_f of strap 2 can be pulled upwards to tighten chest strap 2 as indicated by block arrow “t” in Fig. 3. Conversely, strap 2 can be pulled upwards to loosen chest strap 2 as indicated by block arrow “1” in Fig. 3. (The loosening can be performed until terminal loop 15 impinges against the slot in the strap adjuster.) A strap adjuster as disclosed herein thus allows a strap to be tightened and loosened as needed to optimize the fit of the harness for a particular wearer. It will be appreciated that although the primary adjustment is performed on strap 2 (e.g. a large amount of “slack” may be removed from strap 2), such an operation will can serve to at least slightly tighten second strap 12, as discussed later herein.

In ordinary use of a safety harness 1, a free end of a strap (e.g. 2_f) will often be at least generally aligned with, and overlapped with, a portion of the strap (e.g. 2) from which it extends. In Fig. 3, the angle at which free end 2_f extends away from strap 2 is exaggerated purely so that the various components of the strap can be more easily seen. In fact, in many embodiments, a safety harness may comprise at least one strap guide that is mounted on the strap in question (e.g. a chest strap) and into which the free end of the strap can be slidably inserted to hold the free end of the strap in a desired position (e.g., to keep the free end from flopping about). In many embodiments such a guide may be slidably movable along the strap in order to accommodate various lengths of the free end of the strap.

Any suitable operation or feature may be used to provide that a free end of a strap cannot pass through a slot of the strap adjuster. Such a feature does not necessarily need to take the form of a terminal loop. Any feature or item that adds sufficient bulk to physically prevent the free end from passing through the slot can be used, to provide that at least on some embodiments, strap 2 is not disconnectable from strap adjuster. For example, such a feature might take the form of e.g. a bulky rivet or similar item that is attached to the free end of the strap. (Any such item will be installed in the factory, in the process of manufacturing the harness.)

A strap adjuster 100 is depicted in exemplary embodiment in Figs. 4-7. Fig. 4 is a perspective side-front view of the adjuster and Fig. 5 is a perspective side-rear view of the adjuster. Fig. 6 is a side- rear view with certain components of the adjuster exploded away from each other as discussed below. Straps are omitted from Figs. 4-6 so that components and features of the strap adjuster itself can be more easily seen. Fig. 7 is a side view of the adjuster showing straps connected thereto as discussed in detail below.

Strap adjuster 100 as shown in Figs. 4-7 comprises a first main body 102 having an upper, clamping end 103 and a lower, attachment end 116; and, a second main body 132 having an upper, clamping end 133 and a lower, attachment end 146. Adjuster 100 thus, when serving e.g. as a chest- strap adjuster, comprises an upper end 153 and a lower end 154. Exemplary adjuster 100 is depicted and described as positioned on the frontal torso of a wearer. Thus, a first side 155 of adjuster 100 may be referred to herein as a front or forward side; a second side 156 of adjuster may be referred to as a rear side. That is, front side 155 may face outwards to be visible, whereas rear side 156 may face toward the chest of a wearer of the harness. Similarly, various components, areas, etc. may be referred to as upper or lower. It is again emphasized that all such descriptions are with reference to a particular embodiment in which the strap adjuster is positioned on the frontal torso of a person, operating so as to adjust the length of a chest strap that approaches the adjuster from above. As noted earlier herein, such descriptions and terminology are not limiting but rather will be straightforwardly applied to a strap adjuster that is mounted in some other location. (Furthermore, it will be appreciated that in actual use, a “front” side of a strap adjuster may not always face forward; for example, the strap on which it is mounted may e.g. become momentarily half-twisted.)

First main body 102 and second main body 132 are pivotally connected to each other by at least one pivotal connection 108 that establishes an axis of rotation 111 about which the main bodies are able to pivotally move relative to each other. In some embodiments, first main body 102 comprising a first central portion 101 from which the upper, clamping end 103 of first main body 102 extends in a first, generally upward direction, and from which the lower, attachment end 116 of first main body 102 extends in a second, generally downward direction. Second main body 132 may similarly comprise a second central portion 131 from which the upper, clamping end 133 of second main body 132 extends in a first, generally upward direction, and from which the lower, attachment end 146 of second main body extends in a second, generally downward direction (noting that in Figs. 4-7, “downward” is toward the left edge of the Figure and “upward” is toward the right edge of the Figure).

In some embodiments, first main body 102 may comprise at least one first arm 117 that extends generally rearward from first central portion 101 of first main body 102, as seen in Fig. 6. Second main body 132 may similarly comprise at least one second arm 147 that extends generally forward from second central portion 131 of second main body 132. The at least one first arm 117 and at least one second arm 147 may be pivotally connected to each other to provide a pivotal connection 108 between the first and second main bodies. As can be most clearly seen in the partially exploded view of Fig. 6, in the particular embodiment depicted, each main body has two such arms (right and left arms). Any number of arms may be used, however. If pairs of arms are used, each mating pair may comprise an individual connection (provided by, e.g., a rivet) therebetween, as in Fig. 6. However, if desired, both connections may use a common axle (e.g. an elongated rod).

Typically, first and second main bodies 102 and 132 will be manufactured separately and then assembled together (e.g. by the formation of a pivotal connection therebetween) to form adjuster 100. In some embodiments, first main body 102 may comprise a single, integral body 162 (as shown in Fig. 6) that integrally includes central portion 101, upper, clamping end 103, and lower, attachment end 116. Second main body 132 may similarly comprise a single, integral body 172 that includes all three corresponding portions. In some embodiments, such a main body may be made of any suitable metal, e.g. steel or aluminum. In various embodiments, such a metal main body may be a forged body or a cast body; or, it may be made of sheet metal that is formed (e.g. bent) into the desired shape using standard sheet metal forming techniques.

In some embodiments a portion of the main body (e.g. including any areas that are to be contacted by the fingers of a wearer in the act of using the adjuster) may be partially encased in an overmolded organic polymeric resin. For example, first central portion 101 of first main body 102 is partially encased within shell 161 that is overmolded over the first central portion 101 of single, integral (e.g. metal) body 162, as shown in Fig. 6. Similarly, second central portion 131 of second main body 132 is partially encased within shell 171 that is overmolded over the second central portion 131 of single, integral (e.g. metal) body 172, also as shown in Fig. 6. Overmolding can be achieved e.g. by taking a previously-formed metal main body and inserting it at least partially into an injection-molding cavity so that an organic polymeric molding resin can be formed atop, and adhered to, the desired portions of the main body.

As noted, first main body 102 of adjuster 100 comprises an upper, clamping end 103; second main body 132 similarly comprises an upper, clamping end 133. One of these upper clamping ends, but not the other, will comprise a through-slot through which a free end 2_f of a harness strap 2 extends as shown in Fig. 7. In the exemplary depictions herein, a through-slot 105 is provided in upper, clamping end 103 of first main body 102; upper, clamping end 133 of second main body 132 does not comprise any such through-slot, as evident in Fig. 6. (In some embodiments, such arrangements may be reversed.)

A strap 2 may thus pass through slot 105 as shown in Fig. 7; such a strap will also pass through a clamping gap 109 that is provided between upper, clamping end 103 of first main body 102 and upper, clamping end 133 of second main body 132, also as shown in Fig. 7. Upper clamping end 103 of first main body 102 may comprise a first engaging surface 104 that may, for example, comprise teeth 107 protruding generally rearwardly therefrom (as seen most easily in Fig. 5). Upper clamping end 133 of second main body 132 may similarly comprise a second engaging surface 134, as seen most easily in Fig. 4. Although the exemplary design of Fig. 4 does not provide second engaging surface 134 with teeth, such items may be present if desired.

Directionality of strap adjuster

Strap adjuster 100 may comprise at least one biasing member 115 that is configured to apply a biasing force that urges the upper, clamping end 103 of first main body 102 and the upper, clamping end 133 of second main body 132 toward each other into a first, closed position. In the first, closed position, a clamping force “c” is applied to the strap 2 that is sufficient to prevent the strap from sliding through clamping gap 109 in a loosening direction (as indicated by arrow “1” in Fig. 7), but still allows the strap to slide through clamping gap 109 in a tightening direction (indicated by arrow “t” in Fig. 7).

Strap adjuster 100 is thus a “directional” adjuster. By this is meant that when the adjuster is in the first, closed position, the adjuster allows the strap to slidably move through the adjuster in a first direction but not in a second direction. Since the biasing force applied by the biasing member will be present without any action needed by the user, a user can thus tighten (but not loosen) the strap without having to manipulate, or perform any action on, the adjuster itself. In other words, a user can tighten the strap by simply grasping the free end 2_f of the strap and pulling on it, but has to actuate the adjuster out of the first, closed position in order to loosen the strap.

Any “teeth” that may be present on engaging surface 104 and/or 134 of the clamping ends of the first and second main bodies may be configured to enhance this characteristic. Thus, in some embodiments at least some such teeth may be e.g. in the general form of triangles or barbs that are swept back in a particular direction to allow the strap to easily slide through clamping gap 109 in that direction but in which the tips of the teeth interfere with (e.g., catch on fibers of) the strap and obstruct or prevent its movement in the other direction. It is further noted that, strictly speaking, macroscopic “teeth” may not necessarily be needed in order to achieve the effects desired herein. Rather, in some embodiments, one or both engaging surfaces 104 and/or 134 may be e.g. textured or otherwise treated or configured to exhibit frictional characteristics (e.g. direction-dependent characteristics) that may provide or enhance these effects.

In contrast to tightening of the strap, loosening of the strap requires manual actuation of the strap adjuster to enable this to occur. Thus, in the depicted embodiment, first main body 102 comprises a first manual -actuation area 106 positioned between pivotal connection 108 and lower, attachment end 116 of first main body 102. Manual -actuation area 106 is on the far (opposite) side of pivotal connection 108 from upper, clamping end 103 of first main body 102. Second main body 132 similarly comprises a second manual-actuation area 136 positioned between pivotal connection 108 and lower, attachment end 146 of second main body 132. Manual-actuation area 136 is on the far side ofthe pivotal connection 108 from upper, clamping end 133 of second main body 132. If desired, one or both manual-actuation areas (particularly if they are located on an overmolded organic polymeric sheath in the general manner described later herein) may be configured so that the user’s fingers can easily locate the areas. For example, a manual-actuation area may comprise a slightly concave “hollow” or similar feature.

A manual force applied to the manual-actuation area 106 of first main body 102 and to the manual-actuation area 136 of second main body 132 (indicated by the “f ’ arrows of Fig. 7), overcomes the above-described biasing force and moves the upper, clamping end 103 of first main body 102 and the upper, clamping end 133 of second main body 132, apart, away from the first, closed position and into a second, open position. In the second, open position the engaging surfaces are far enough apart from each other that the strap 2 can now slide through clamping gap 109 in the second, loosening direction “1” of Fig. 7. (The strap may now be even more easily able to move in the first, tightening direction “f ’.)

Thus, a user may grasp strap adjuster 100 and apply a squeezing force to actuation areas 106 and 136, which moves these areas toward each other and moves clamping ends 103 and 133 away from each other, to allow the strap to be loosened. In other words, a user can loosen strap 2 by squeezing the appropriate areas of the adjuster 100 and, while squeezing the adjuster, grasping the “non-free” end of the strap (e.g. the portion of a chest strap 2 that continues upward to become the shoulder strap) and pulling upwards on it on it.

In the illustrated embodiment, biasing member 115 is a coil spring that is mounted generally in a space between the first central portion 101 of first main body 102, and the first central portion 131 of second main body 132. In the depicted embodiment, exemplary coil spring 115 is positioned on the far side of the pivotal connection 108 from the clamping ends 103 and 133 of the main bodies and is mounted in compression so that the expansion force exerted by the coil spring causes the clamping ends 103 and 133 to be urged toward each other (i.e., toward a closed (gripping) position).

It will be appreciated that any suitable biasing member may be used, of any type, in any suitable location. Such a member does not have to be mounted in compression and does not have to be positioned as shown in the Figures herein. For example, a coil spring might be installed forward of the pivotal connection 108, acting in tension, so that the spring pulls upper ends 103 and 133 of the main bodies toward each other. Any spring that is used as a biasing member need not necessarily be a coil spring but could rather be a torsion spring, a leaf spring or any other design.

The above discussions make it clear that in many uses, one strap (e.g. a chest strap 2) is adjustably connected to the strap adjuster in the general manner described above. In many such embodiments, a second strap (e.g. an abdominal strap 12) may be non-adjustably connected (attached) to the strap adjuster, e.g. to the lower end of the adjuster. By non-adjustably connected is meant that the length of the second strap is not widely adjustable in the way that the length of the first strap is adjustable. (Rather, the most that can typically be done with the second strap is to tighten it, e.g. removing a small amount of slack in the process.) Also as noted previously, one way in which an end of second strap can be non-adjustably attached to the strap adjuster is to pass the end of the strap through a slot of the strap adjuster and then turn the end of the strap back on the strap and attach it to form a terminal loop that is captured in the slot in the general manner shown in Fig. 3.

As shown e.g. in Fig. 4, in some embodiments a strap adjuster 100 may be configured to have one slot 113 in a lower, attachment end 116 of first main body 102; and to have another slot 143 in a lower, attachment end 146 of second main body 132. In some embodiments a terminal end of a second strap 12 can be passed through both slots 113 and 143 and can be turned back on the strap to form a terminal loop 14 that is captured in both slots as shown in Fig. 7. (This end of the strap adjuster and the main bodies thereof is thus referred to herein as an attachment end, signifying that a strap is non- adjustably connected (attached) to this end, thus distinguishing from the other end of the strap adjuster.)

Strap adjuster can be self-snugging

Such an arrangement can allow strap adjuster 100 to be “self-snugging”, described as follows. With a strap adjuster configured in the general manner depicted in Fig. 7, the length of first strap 2 can be adjusted, i.e. shortened, by pulling upward on free end 2_fas discussed above. This will remove any slack from the first strap, and tighten it. Toward the end of this process, the tightening of first strap 2 will cause second strap 12 to become taut. This will tighten loop 14 of strap 12 thus causing a snugging force (indicated by arrow “s” in Fig. 7) to be applied to lower ends 116 and 146 of main bodies 102 and 132. The snugging force will cause these lower ends 116 and 146 of main bodies 102 and 132 to be urged toward each other. Because of the design of the main bodies, this movement of the lower ends 116 and 146 of the main bodies will cause the upper, clamping ends 103 and 133 of the main bodies to move closer to each other. This will apply an additional clamping force (“c” in Fig. 7) above and beyond that caused by the biasing member 115. The additional clamping force will be present as long as second strap 12 is tight enough to exert a force to urge lower ends 116 and 146 toward each other.

Such an arrangement is self-snugging in the sense that pulling first strap 2 tight will cause a tightening force to be applied to second strap 12, which will in turn cause the clamping ends of the adjuster to grip first strap 2 more tightly than it would be gripped purely by the action of the biasing member. This can enhance the above-described directional functioning of the strap adjuster; for example, a tightened strap may be less likely to e.g. gradually loosen.

Such a self-snugging property may be enhanced by arranging the strap adjuster so that the lower ends 116/146 of the strap adjuster have mechanical advantage over the clamping ends 103/133. This can be achieved by providing that the lever arm obtained by the lower ends is greater than the lever arm obtained by the clamping ends. This can be characterized as indicated by dashed arrows 176 and 196 in Fig. 7. Dashed arrow 176 denotes the linear distance, along the long axis of the strap adjuster, from axis of rotation 111 (defined by pivotal connection 108) to the lowermost edge of slot 113 of lower end 146 of first main body 102. Dashed arrow 196 denotes the linear distance from axis of rotation 111 to the uppermost edge of slot 105 of clamping end 103 of first main body 102. (These are edges of slots that straps 12 and 2 will be respectively pulled tight against, when the straps are tightened.) Ordinary artisans will appreciate that mechanical advantage will result from the longer lever arm achieved by positioning the edge of slot 113 of lower end 116 of first main body 102 (and the edge of slot 143 of lower end 146 of second main body 132) further from axis of rotation 111, in comparison to the distance from the axis of rotation 111 to the edge of slot 105 of clamping end 103. This means that the above-discussed snugging force “s” imparted by strap 12 on the lower ends 116 and 146 of the strap adjuster will cause a magnified clamping force “c” of clamping ends 103 and 133 on strap 2. Such arrangements can further enhance the self-snugging aspect of the strap adjuster.

In various embodiments the above-described lever arm, as characterized by the ratio of the length of the above-described arrow 176 to the length of the above-described arrow 196, can be at least 1.1, 1.2, 1.3, 1.4, 1.6, 1.8, or 2.0. In further embodiments such a ratio may be at most 2.3, 2.1, 1.9, 1.7, 1.5, 1.35, 1.25, or 1.15.

It will be appreciated that such a functionality requires that strap adjuster 100 be configured so that movement of the lower ends 116 and 146 of the adjuster closer together, causes the upper ends 103 and 133 of the adjuster to move closer together. Such a functionality can be achieved by the exemplary arrangements depicted in the Figures herein. As seen most easily in Fig. 4, in some embodiments the lower, attachment end 116 of first main body 102 may be connected to the first, central portion 101 of first main body 102 by first and second struts 118 and 119 that establish a through-opening 114 therebetween. The lower, attachment end 146 of second main body 132 may be connected to second, central portion 131 of second main body 132 by a third strut 140 that passes through the through- opening 114 between first and second struts 118 and 119. The third strut 140 can thus be arranged relative to the first two struts 118 and 119 in a “criss-cross” or “X” configuration that transforms movement of lower ends 116 and 146, into similar movement of upper ends 103 and 133. It will be appreciated that the number, size, shape, etc., of any such struts may be varied as desired while retaining the above-described functionality.

In some embodiments, upper, clamping end 103 of first main body 102 may be connected to central portion 101 of first main body 102, e.g. by two struts 110 and 112 as most easily seen in Figs. 5 and 6. In the illustrated embodiment, upper, clamping end 133 of second main body 132 is connected to central portion 131 of second main body 132 by a single strut 142. However, the number, size, shape, etc., of any such struts may be varied as desired.

In many embodiments, a strap adjuster as disclosed herein may be produced in a relatively straightforward manner, with a minimum of separately-made parts to be assembled. Thus for example, first and second main bodies may be produced, e.g. by any suitable metal-forming method. A desired portion of each main body may be overmolded with an organic polymeric resin if desired. The main bodies may then be assembled together, capturing a biasing member (e.g. a coil spring) in a space between the main bodies, with the main bodies being connected to each other e.g. by one or more rivets, axles or the like, to provide a pivotal connection. The exemplary illustrations of Figs. 4, 5 and 7 depict a strap adjuster in a position that is partly between the above-described open and closed positions. Artisans in the field will easily be able to appreciate how the illustrated adjuster would appear in each of those positions. In the depicted exemplary embodiment, first main body 102 and second main body 132 exhibit differences e.g. in the number of struts that connect the upper and lower ends to the central portion of each main body, the presence or absence of teeth in the engaging surface of the upper end of the main body, and, in the size and shape of the central portion of each main body. It is emphasized that either of the main bodies may be configured, modified, etc., so as to have any of the features exhibited on either main body in the figures herein, while remaining within the scope of the disclosures herein.

A strap adjuster as disclosed herein can be used with any suitable fall-protection harness. Such harnesses are well known and may be used with a wide variety of fall-protection apparatus, methods and systems. Fall-protection apparatus and systems (e.g. lanyards, self-retracting lifelines, positioning systems, horizontal systems, vertical systems, and so on), fall-protection anchorages, components of such apparatus, systems, equipment, and so on, with which the arrangements disclosed herein may find use, are described e.g. in the 3M DBI-SALA Fall Protection Full Line Catalog 2018. Particular fall- protection apparatus such as self-retracting lifelines and components and functioning thereof are described in various aspects in U.S. Patents 7843349, 8256574, 8430206, 8430207, and 9488235, all of which are incorporated by reference in their entirety herein.

It is emphasized that a user of any fall-protection device, apparatus, system, or component thereof that includes a harness and/or strap adjuster as described herein is tasked with carrying out any appropriate steps, actions, precautions, operating procedures, etc., as required by applicable laws, rules, codes, standards, and/or instructions. That is, under no circumstances will the presence of any arrangement disclosed herein relieve a user of the duty to follow all appropriate laws; rules; codes; standards as promulgated by applicable bodies (e.g., ANSI); instructions as provided by the manufacturer of the fall-protection system, apparatus or components; instructions as provided by the entity in charge of a worksite, and so on.

In summary, all such variations and combinations are contemplated as being within the bounds of the conceived invention, not merely those representative designs that were chosen to serve as exemplary illustrations. Thus, the scope of the present invention should not be limited to the specific illustrative structures described herein, but rather extends at least to the structures described by the language of the claims, and the equivalents of those structures. Any of the elements that are positively recited in this specification as alternatives may be explicitly included in the claims or excluded from the claims, in any combination as desired. Any of the elements or combinations of elements that are recited in this specification in open-ended language (e.g., comprise and derivatives thereof), are considered to additionally be recited in closed-ended language (e.g., consist and derivatives thereof) and in partially closed-ended language (e.g., consist essentially, and derivatives thereof). Although various theories and possible mechanisms may have been discussed herein, in no event should such discussions serve to limit the claimable subject matter. To the extent that there is any conflict or discrepancy between this specification as written and the disclosure in any document that is incorporated by reference herein but to which no priority is claimed, this specification as written will control.

Claims

What is claimed is:

1. A fall-protection safety harness with at least one directional strap adjuster to which is adjustably connected a first strap of the harness, comprising: a directional strap adjuster comprising a first main body having an upper, clamping end and a lower, attachment end, and a second main body having an upper, clamping end and a lower, attachment end, the first main body and the second main body being pivotally connected to each other by a pivotal connection, the first main body comprising a first manual-actuation area positioned between the pivotal connection and the lower, attachment end of the first main body and on the far side of the pivotal connection from the upper, clamping end of the first main body, and the second main body comprising a second manual-actuation area positioned between the pivotal connection and the lower, attachment end of the second main body and on the far side of the pivotal connection from the upper, clamping end of the first main body; wherein a free end of the first strap of the harness extends through a slot in the upper, clamping end of the first main body and continues through a clamping gap between the upper, clamping end of the first main body and the upper, clamping end of the second main body; wherein the strap adjuster comprises a biasing member configured to apply a biasing force that urges the upper, clamping end of the first main body and the upper, clamping end of the second main body toward each other into a first, closed position, in which a clamping force is applied to the first strap that allows the free end of the first strap to slide through the clamping gap in a first, tightening direction but prevents the free end of the first strap from sliding through the clamping gap in a second, opposite, loosening direction; wherein the strap adjuster is further configured so that a manual force applied to the manual-actuation area of the first main body and to the manual-activation area of the second main body, overcomes the biasing force and moves the upper, clamping end of the first main body and the upper, clamping end of the second main body, apart into a second, open position, in which the free end of the first strap can slide through the clamping gap in the first, tightening direction and can slide through the clamping gap in the second, opposite, loosening direction.

2. The fall-protection safety harness of claim 1 wherein the strap adjuster is a self-snugging strap adjuster in which a second strap of the safety harness is attached to a lower end of the strap adjuster by way of a terminal loop of the second strap of the safety harness passing through a first slot in the lower, attachment end of the first main body and continuing through a second slot in the lower, attachment end of the second main body, so that when the free end of the first strap is slidably moved through the clamping gap in the first, tightening direction to tighten the first strap, the terminal loop of the second strap applies a force that urges the lower, attachment end of the first main body and the lower, attachment end of the second main body toward each other to apply an additional clamping force to the first strap in addition to the clamping force that is provided by the biasing member.

3. The fall-protection safety harness of claim 2 wherein a ratio of a linear distance, along a long axis of the strap adjuster, from an axis of rotation defined by a pivotal connection of the strap adjuster to a lowermost edge of the first slot in the lower, attachment end of the first main body, to a linear distance from the axis of rotation to the slot in the upper, clamping end of the first main body, is at least 1.3.

4. The fall-protection safety harness of any of claims 2-3 wherein the first main body of the strap adjuster comprises a first central portion from which the upper, clamping end of the first main body extends in a first, generally upward direction, and from which the lower, attachment end of the first main body extends in a second, generally downward direction; and, wherein the second main body of the strap adjuster comprises a second central portion from which the upper, clamping end of the second main body extends in a first, generally upward direction, and from which the lower, attachment end of the second main body extends in a second, generally downward direction.

5. The fall-protection harness of any of claims 1-4 wherein the first main body and the second main body are configured so that application of a manual squeezing force to the manual-actuation area of the first main body and to the manual-activation area of the second main body, causes the upper, clamping end of the first main body and the upper, clamping end of the second main body to move apart into the second, open position; and, causes the lower, attachment end of the first main body and the lower, attachment end of the second main body to move apart from each other.

6. The fall-protection harness of any of claims 4-5 wherein the first central portion and the upper, clamping end and the lower attachment end of the first main body are all portions of a single, integral first main body that is made of metal; and, wherein the second central portion and the upper, clamping end and the lower attachment end of the second main body, are all portions of a single, integral second main body that is made of metal.

7. The fall-protection harness of claim 6 wherein the lower, attachment end of the first main body is integrally connected to the first, central portion of the first main body by first and second struts that establish a through-opening therebetween; and, wherein the lower, attachment end of the second main body is integrally connected to the second, central portion of the second main body by a third strut that passes through the through-opening between the first and second struts.

8. The fall-protection harness of any of claims 4-7 wherein the first main body comprises at least one first arm that extends generally rearward from the first central portion of the first main body, wherein the second main body comprises at least one second arm that extends generally forward from the second central portion of the second main body, and wherein the at least one first arm and the at least one second arm are connected to each other to provide the pivotal connection between the first main body and the second main body.

9. The fall-protection harness of claim 8 wherein the first main body comprises right and left first arms and the second main body comprises right and left second arms, and wherein the right arms are connected to each other and the left arms are connected to each other to provide the pivotal connection between the first main body and the second main body.

10. The fall-protection harness of any of claims 4-9 wherein the first main body is made of metal and wherein at least a portion of the first central portion of the first main body is partially encased within a first overmolded organic polymeric resin; and, wherein the second main body is made of metal and wherein at least a portion of the second central portion of the second main body is partially encased within a second overmolded organic polymeric resin.

11. The fall-protection harness of any of claims 1-10 wherein the biasing member is a coil spring that is mounted in compression in a space between the first central portion of the first main body and the second central portion of the second main body.

12. The fall-protection harness of any of claims 1-11 wherein the upper, clamping end of the first main body and/or the upper, clamping end of the second main body, comprises an engaging surface with teeth protruding therefrom, the teeth being oriented so as to allow the free end of the first strap to slide through the clamping gap in the first, tightening direction but to interfere with slidable movement of the free end of the first strap through the clamping gap in the second, opposite, loosening direction.

13. The fall-protection harness of any of claims 1-12 wherein the free end of the first strap comprises a terminal loop that is sized to prevent the free end of the first strap from being removed from the slot in the upper, clamping end of the first main body.

14. The fall-protection harness of any of claims 1-13 wherein the first strap that is adjustably connected to an upper end of the strap adjuster, is a chest strap that extends generally upward from the strap adjuster and continues over the wearer’s shoulder as a shoulder strap.

15. The fall-protection harness of any of claims 1-14 wherein a second strap of the safety harness that is attached to a lower end of the strap adjuster, is an abdominal strap that extends generally downward from the strap adjuster and continues as, or is connected to, a waist, hip, and/or leg strap of the harness.

16. The fall-protection harness of claim 15 wherein no part of the strap adjuster is disconnectable from any other part of the strap adjuster and wherein the first and second straps are not disconnectable from the strap adjuster.

17. The fall-protection harness of any of claims 15-16 wherein the harness comprises a first, left strap adjuster that adjustably connects a left chest strap of the harness with a left abdominal strap of the harness, and a second, right strap adjuster that adjustably connects a right chest strap of the harness with a right abdominal strap of the harness.

18. The fall-protection harness of any of claims 14-17 wherein the harness comprises at least one guide that is mounted on the chest strap and is slidably movable along the chest strap and into which the free end of the chest strap can be slidably inserted to hold the free end of the chest strap in a desired position.

19. The fall-protection harness of any of claims 1-18 wherein the first and second main body are each made of forged steel.

20. The fall-protection harness of any of claims 1-19 wherein the harness, and the strap adjuster, meet the requirements of ANSI Z359.12.