Patent Publication Number: US-2021178203-A1

Title: Mid-truss anchor clamp

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a Divisional of U.S. patent application Ser. No. 15/627,581, filed Jun. 20, 2017, which claims the benefit of U.S. Provisional Patent Application Ser. No. 62/352,150 filed Jun. 20, 2016. The entire disclosures of these two applications are incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     Technical Field 
     The present disclosure is generally related to building products. More particularly, the present disclosure is directed to products used during construction of a roof. Specifically, the disclosure relates to an anchor clamp for a safety anchoring system used to aid in arresting falls. The anchor clamp comprises a generally U-shaped member that is selectively engageable with a roof truss rafter at a position between an apex and a wall-frame end of the truss. A worker&#39;s safety harness is selectively engageable with the U-shaped member. The anchor clamp remains secured to the rafter and be readily locatable and usable during subsequent construction procedures performed on the roof such as carpentry and during installation of HVAC vents, plumbing vents, and rain ware. 
     Background Information 
     Roofers, workers and tradesmen may be required to spend a considerable amount of time on structures located a distance vertically above a ground surface such as a roof. One of the problems that such workers face is the potential for falling off a partially constructed or fully constructed roof. In order to address this issue, a variety of differently shaped and configured safety harnesses and roof anchors have been suggested in the prior art. In most of these systems, the worker wears a harness and utilizes a carabiner or D-clamp at an end of a lanyard secured to the harness to tie himself or herself off to a safety anchor on the roof. It is important that such roof anchors be relatively quickly and easily installed or the worker may decide that he or she is too busy to secure an anchor so that they can then tie off. If a safety anchor is not utilized, the worker is potentially in danger from falling off the roof and there is a potential liability issue for the owner of the building and/or for the company that employs the worker. 
     SUMMARY 
     The device disclosed herein is a mid-truss anchor clamp that is capable of being quickly and easily installed on an already-erected roof truss. This anchor clamp is suitable for use as a quick connection point for a safety anchor. 
     A roof truss anchor clamp for use with a worker&#39;s safety harness, a safety system incorporating the anchor clamp and a method of using the same is disclosed herein. The anchor clamp may include a middle wall; a first side wall extending outwardly from one end of the middle wall; and a second side wall extending outwardly from an opposite end of the middle wall. The middle wall is positionable adjacent an upper surface of a section of a roof truss rafter. A space is defined in the anchor clamp between the first and second side walls and the section of the rafter is receivable in this space. A fastener assembly is provided on the anchor clamp for securing the clamp to the rafter. A connector is also provided on the anchor clamp for securing a worker&#39;s safety harness thereto. 
     In one aspect, the disclosure may provide a roof truss anchor clamp for use with a worker&#39;s safety harness; said anchor clamp comprising a first side wall adapted to be positioned adjacent a first side surface of a roof rafter; a fastener assembly that is adapted to secure the anchor clamp to the roof rafter; 
     and a connector assembly provided on the anchor clamp and adapted to selectively engage a connector secured to the worker&#39;s safety harness. 
     In another aspect, the disclosure may provide a safety system for securing a worker to a roof rafter; said safety system comprising a safety harness wearable by the worker; a lanyard connected at a first end to the safety harness and having a connector provided at a second end thereof; an anchor clamp engageable on a section of a roof truss rafter; said anchor clamp comprising a first side wall adapted to be positioned adjacent a first side of the roof rafter; a second side wall adapted to be positioned adjacent a second side of the roof rafter; a fastener assembly securing the first and second side walls together; and a connector assembly provided on the anchor clamp; wherein the connector from the safety harness is selectively engageable with the connector assembly. 
     In another aspect, the present disclosure may provide a method of securing a worker to a section of a roof truss comprising engaging an anchor clamp to a rafter of the roof truss comprising steps of positioning a middle wall of the anchor clamp against an upper surface of a section of the rafter; positioning a first side wall extending outwardly from one side of the middle wall adjacent a first side surface of the rafter; positioning a second side wall extending outwardly from an opposite side of the anchor&#39;s clamp&#39;s middle wall adjacent a second side surface of the rafter; engaging a fastener between the first side wall and the second side wall; and engaging a connector provided at one end of a lanyard extending from a worker&#39;s safety harness to the anchor clamp. 
     The step of engaging the anchor clamp to the rafter further comprises positioning a first slot defined in a lower end of the first side wall of the anchor clamp a distance below a lower surface of the rafter; positioning a second slot defined in a lower end of the second side wall of the anchor clamp a same distance below the lower surface of the rafter; at least partially aligning the first slot with the second slot; extending a fastener through the at least partially aligned first slot and second slot; and securing the fastener to the first and second side walls of the anchor clamp. 
     The step of engaging the connector may further comprise moving the anchor clamp outwardly relative to the upper surface of the rafter; separating the middle wall of the anchor clamp from the upper surface of the rafter; inserting the connector through a hole defined in the anchor clamp&#39;s middle wall; and moving the anchor clamp downwardly so that the middle wall is positioned adjacent the upper surface of the rafter. 
     The method may further comprise locating an anchor clamp cover provided on a roof; disengaging the cover from the roof; exposing a hole beneath the cover; locating, through the hole, the anchor clamp mounted on the roof rafter; and inserting the connector through the hole in the roof prior to engaging the connector with the anchor clamp. Still further, middle wall may comprise a protector plate separate from the first side wall and the second side wall; and said method further comprises passing a shaft of a second fastener through a bore defined by the protector plate and through aligned holes in the first and second side walls of the anchor clamp. 
     In yet another aspect, the present disclosure may provide a roof truss anchor clamp for use with a worker&#39;s safety harness; said anchor clamp comprising a U-shaped member comprising a middle wall adapted to be positioned adjacent an upper surface of a section of a roof truss rafter; a first side wall extending outwardly from one end of the middle wall; and a second side wall extending outwardly from an opposite end of the middle wall; wherein a space is defined between the first and second side walls and is adapted to receive the section of the rafter therein; a fastener assembly provided on the first and second side walls; and a connector assembly provided on the middle wall. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       A sample embodiment of the disclosure is set forth in the following description, is shown in the drawings and is particularly and distinctly pointed out and set forth in the appended claims. The accompanying drawings, which may be fully incorporated herein and constitute a part of the specification, illustrate various examples, methods, and other example embodiments of various aspects of the disclosure. It will be appreciated that the illustrated element boundaries (e.g., boxes, groups of boxes, or other shapes) in the figures represent one example of the boundaries. One of ordinary skill in the art will appreciate that in some examples one element may be designed as multiple elements or that multiple elements may be designed as one element. In some examples, an element shown as an internal component of another element may be implemented as an external component and vice versa. Furthermore, elements may not be drawn to scale. 
         FIG. 1  is a top perspective view of roof incorporating a first embodiment of an anchor clamp in accordance with an aspect of the present disclosure; the figure shows a worker in a safety harness crouching on the roof and getting ready to secure his safety lanyard to the anchor clamp; 
         FIG. 2  is a perspective view of the first embodiment anchor clamp in accordance with an aspect of the present disclosure; 
         FIG. 3  is a front elevational view of the anchor clamp; 
         FIG. 4  is a right side elevational view of the anchor clamp; 
         FIG. 5  is a top plan view thereof; 
         FIG. 6  is a bottom plan view thereof; 
         FIG. 7  is a front elevational view of the anchor clamp shown mounted on a side surface of a rafter of a roof truss, with the anchor clamp shown in a first position; 
         FIG. 8  is a cross-section taken along line  8 - 8  of  FIG. 7 ; 
         FIG. 9  is a front view of the anchor clamp mounted on a rafter of a roof truss in a second position where a safety anchor is engaged with the anchor clamp; 
         FIG. 10  is a cross-section taken along line  10 - 10  of  FIG. 9 ; 
         FIG. 11  is a perspective view of a second embodiment of an anchor clamp in accordance with an aspect of the invention; 
         FIG. 12  is a side elevational view thereof; 
         FIG. 13  is a front elevational view thereof; 
         FIG. 14  is a front elevational view of an anchor clamp assembly that may include two anchor clamps, engaged with an anchor plate that is secured to a truss in an off-peak position; and where the anchor clamp assembly is shown in a retracted position; 
         FIG. 15  is an enlargement of the highlighted region of  FIG. 14 ; 
         FIG. 16  is an enlarged front elevational view of the anchor clamp assembly shown in a protracted position; 
         FIG. 16A  is an enlarged front elevational view of the anchor clamp assembly shown in a protracted position, wherein the assembly also may include a crossover plate that is engaged with the anchor clamp and the anchor plate; 
         FIG. 17  is a side elevational view of the anchor clamp assembly shown in  FIG. 16 ; 
         FIG. 17A  is a side elevational view of the anchor clamp assembly shown in  FIG. 16A ; 
         FIG. 18  is a front elevational view of the anchor clamp assembly showing a fall arrest event; 
         FIG. 19  is a front elevation view of a first embodiment of a protector plate for use with the anchor clamp; and where the protector plate is shown on its own; 
         FIG. 20  is a cross-section of the protector plate taken along line  20 - 20  of  FIG. 19 ; 
         FIG. 21  is an enlarged front elevational view of the anchor clamp assembly that includes the protector plate of  FIG. 19  shown positioned on a upper surface of a rafter chord; 
         FIG. 22  is a front elevation view of a second embodiment of a protector plate shown on its own; 
         FIG. 23  is a cross-section of the protector plate taken along line  23 - 23  of  FIG. 22 ; 
         FIG. 24  is an enlarged front elevational view of the anchor clamp assembly that includes the protector plate of  FIG. 22 ; 
         FIG. 25  is a front elevation view of a third embodiment of the protector plate shown on its own; and 
         FIG. 26  is a cross-section of the protector plate taken along line  26 - 26  of  FIG. 25 ; 
         FIG. 27  is an enlarged front elevational view of the anchor clamp assembly using the protector plate of  FIG. 25 ; and 
         FIG. 28  is an enlarged front elevational view of the anchor clamp assembly that includes the first embodiment of the anchor clamp and the third embodiment of the protector plate. 
     
    
    
     DETAILED DESCRIPTION 
       FIGS. 1-27  show an anchor clamp assembly in accordance with the present disclosure. Referring to  FIG. 1 , there is shown a roof  10  of a building. Roof  10  is comprised of a plurality of roof trusses  12  erected onto previously installed wall frames  14 . Each truss  12  is comprised of a plurality of rafters or chords  16  that may be joined together by various metal plates  18  or any other suitable type of joining mechanism. Each truss  12  has an apex  12   a  and ends  12   b . Ends  12   b  may be engaged with wall frame  14 . (Only one of ends  12   b  is illustrated in  FIG. 1  but it will be understood that the opposite end of truss  12  is similarly mounted to an opposed wall frame.)  FIG. 8  shows each rafter  16  has an upper surface  16   a , a bottom surface  16   b , a first side surface  16   c , and a second side surface  16   d . Roof  10  is further comprised of a plurality of planar sheets  20 , such as plywood sheets, that may be secured to rafters  16 . Sheets  20  may be supported on upper surfaces  16   a  of a plurality of rafters  16  and may be secured to upper surfaces  16   a  of those rafters in any appropriate manner known in the art. 
     In accordance with an aspect of the current disclosure, one or more holes  22  may be cut into the plywood sheets  20 . These holes  22  may be provided to allow access to a particular section of at least one rafter  16  and to the anchor clamp mounted thereon. The anchor clamp is identified in the figures and in this description by the reference number  24  and will be described in greater detail hereafter. Anchor clamp  24  may be installed on a section of rafter  16  that is located approximately midway between apex  12   a  and the end  12   b  of truss  12  which is engaged with wall frame  14 . Anchor clamp  24  may therefore be referred to as a “mid-truss anchor clamp”. 
     Anchor clamp  24  may be used by a worker  26  to secure himself or herself while he or she works on the roof  10 . The worker  26  puts on a safety harness  28 . A lanyard  30  is connected at one end to safety harness  28  and a second end of lanyard  30  may include a safety harness connector  32  such as a carabiner or D-clip. Connector  32  is selectively engaged with anchor clamp  24  (as will be later described herein), thereby securing worker  26  to rafter  16 . Once worker  26  has finished working on roof  10 , he or she may place an anchor clamp cover  34  over hole  22  and use fasteners  36  to secure cover  34  back to sheet  20  or to the roof truss As is evident from  FIG. 1 , a plurality of such covers  34  (and therefore associated holes  22  and anchor clamps  24 ) may be provided on a single roof  10 . Each cover  34  closes off access to one of the holes  22  in roof  10  and this ensures that roof  10  will be substantially continuous. Shingles, roof tiles  38 , or any other suitable finishing material may be applied over sheets  20  and covers  34  to complete the construction and finishing of roof  10 . Once roof  10  is shingled, the positions of the various covers  34  and therefore of the various anchor clamps  24  may be hidden. During a later reroofing operation, when shingles  38  are removed, covers  34  will again be visible. Covers  34  may therefore provide an immediate reference to a new worker as to where they may be able to access an anchor clamp  24  to which they can secure their safety harness. In order to access anchor clamp  24 , the future worker will disengage fasteners  36 , remove cover  34  and thereby expose hole  22  and anchor clamp  24 . The worker will then be able to tie off their own safety harness to the already installed anchor clamp  24 . The method of placing the anchor clamp under the roofing and covers  34  protects the anchor clamp  24  from weathering, thereby preserving the device for future use. (It should be noted that prior art devices anchor devices were installed in such a way that parts of the prior art devices extended above the roofline thus exposing the metal to corrosive weather elements.) 
     Referring now to  FIGS. 2-6 , anchor clamp  24  is described in greater detail. Anchor clamp  24  may be a generally U-shaped component that is integrally formed from metal. The U-shaped component may include a middle wall  40 , a first side wall  42 , and a second side wall  44 . Middle wall  40  may have an exterior surface  40   a , an interior surface  40   b , a first side  40   c , a second side  40   d , a first end  40   e , and a second end  40   f . First side wall  42  may include an exterior surface  42   a , an interior surface  42   b , a first side  42   c , a second side  42   d , a first end  42   e , and a second end  42   f . Second side wall  44  may include an exterior surface  44   a , an interior surface  44   b , a first side  44   c , a second side  44   d , a first end  44   e , and a second end  44 . First side  40   c  of middle wall  40  may be integral with first side  42   c  of first side wall  42  and form one corner of the U-shaped component. Second sides  42   d ,  44   d  may comprise terminal ends of the U-shaped component when that component is engaged on a section of rafter  16 . Second side  40   d  of middle wall  40  may be integral with first side  44   c  of second side wall  44  and form another corner of the U-shaped component. 
     Each of the first and second side walls  42 ,  44  may extend outwardly from opposite sides  40   c ,  40   d  of middle wall  40  and be positioned a distance apart from each other. Each side wall  42 ,  44  may be oriented at about 90° relative to middle wall  40 . Middle wall  40  and first and second side walls  42 ,  44  may bound and define a space  46  ( FIG. 2 ) shaped and sized to receive a section of rafter  16  therein. Anchor clamp  24  may have a width “W” and a length “L” ( FIG. 4 ). Width “W” may be at least as wide as rafter  16  (i.e., at least as wide as a distance between first and second side surfaces  16   c ,  16   d  of rafter  16 ). Length “L” of anchor clamp may be longer than a distance “D” ( FIG. 8 ) between upper surface  16   a  and bottom surface  16   b  of rafter  16 . 
     Referring again to  FIGS. 2-6 , middle wall  40   a  may define an elongate hole  48  therein. Hole  48  may be located closer to second end  40   f  than to first end  40   e  and is a through-hole extending between exterior and interior surfaces  40   a ,  40   b . Hole  48  may be positioned equidistant from first and second sides  40   c ,  40   d.    
       FIG. 3  shows that first side wall  42  may define a pair of spaced-apart apertures  50  and a pair of spaced apart slots  52  therein. Each aperture  50  may be a through-aperture extending between exterior and interior surfaces  42   a ,  42   b  and be located proximate an upper end of first side wall  42 . Furthermore, each aperture  50  may be located a short distance inwardly away from first end  42   c  and one or the other of first and second sides  42   e ,  42   f . Each slot  52  may be defined in a lower end of first side wall  42 . Slots  52  may be through-slots extending between exterior and interior surfaces  42   a ,  42   b . Each slot  52  may be located a short distance inwardly away from second end  42   d  and from one or the other of first and second sides  42   e ,  42   f . Each slot  52  may be positioned so as to be vertically out of alignment with the one of the apertures  50  adjacent the same one of the first and second sides  42   e ,  42   f . This is illustrated in  FIG. 3 . In other words, slot  52  may be located further away from the associated first or second side  42   e ,  42   f  than from the associated aperture  50 . 
     Alternatively, slots  52  may be vertically aligned with the associated aperture  50  or may be located closer to the associated first or second side  42   e ,  42   f  than is the associated aperture  50 . In other words, each slot  52  may be spaced the same distance away from the first or second side  42   e ,  42   f  as the associated aperture  50  or closer relative thereto. 
     In a similar fashion, a lower end of second side wall  42  may define a pair of spaced-apart apertures  54  and a pair of spaced apart slots  56  therein. Each aperture  55  may be a through-aperture extending between exterior and interior surfaces  44   a ,  44   b . Furthermore, each aperture  55  may be located a short distance inwardly away from first end  44   c  and one or the other of first and second sides  44   e ,  44   f . Slots  56  may be through-slots extending between exterior and interior surfaces  44   a ,  44   b . Each slot  56  may be located a short distance inwardly away from second end  44   d  and one or the other of first and second sides  44   e ,  44   f . Each slot  56  may be vertically out of alignment with the one of the apertures  54  adjacent the same one of the first and second sides  44   e ,  44   f  (as illustrated in  FIG. 2 ). In other words, the slot  56  may be located further away from the associated first or second side  44   e ,  44   f  than is the associated aperture  54 . Alternatively, the slots  56  may be vertically aligned with the associated aperture  54 . In other words, each slot  56  may be spaced the same distance away from the first or second side  44   e ,  44   f  as the associated aperture  54 . Additionally, holes  50  and  54  may be laterally aligned with each other and slots  52  and  56  may be laterally aligned with each other. This alignment may include the entire hole  50 ,  54  or only a portion thereof; and the entire slot  52 ,  56  or only a portion thereof. 
     Referring to  FIGS. 7-10  there is shown a method of installing and using anchor clamp  24 . Anchor clamp  24  may be inserted through hole  22  in sheet  20  and be positioned against rafter  16 . This may be accomplished by orienting anchor clamp  24  so that the U-shaped component may be located at right angles relative to a longitudinal axis “Y” ( FIG. 7 ) of rafter  16  and so that clamp  24  may be positioned to receive a section of the rafter  16  into space  46 . Anchor clamp  24  may be moved downwardly in the direction of arrow “A” until interior surface  40   b  ( FIG. 8 ) is adjacent upper surface  16   a  of rafter  16 . Anchor clamp  24  may be further positioned so that interior surface  42   b  of first side wall  42  may be adjacent first side surface  16   c  of rafter  16  and interior surface  44   b  of second side wall  44  may be positioned adjacent second side surface  16   d  of rafter  16 . 
     Once anchor clamp  24  is in the above-mentioned position on rafter  16 , a pair of fasteners  58  may be used to secure or lock anchor clamp  24  to rafter  16 . Each fastener  58  may, for example, comprise a bolt  60 , one or more washers  62 , and a nut  64 . The shaft  60   a  of each bolt  60  may be inserted through one of the slots  52  or  56  and may then be loosely tightened to secure the bolt  60  to anchor clamp  24  while still permitting relative movement between fastener  58  and anchor clamp  24 . 
       FIG. 9  shows lanyard  30  from safety harness  28  being engaged with anchor clamp  24 . In order to make this engagement, the worker  26  may pull anchor clamp  24  outwardly and upwardly away from upper surface  16   a  of rafter  16 . This may be done by grasping the sides  42 ,  44  or bottom end  42   d ,  44   d  of clamp  24  and moving clamp  24  in the direction indicated by arrow “B”. Because slots  56  are elongate in the direction of this movement and because fasteners  58  may be only loosely tightened, anchor clamp  24  and bolts  58  will move upwardly in the direction of arrow “B”, thereby separating middle wall  40  of anchor clamp  24  from upper surface  16   a  of rafter  16 . The movement in the direction of arrow “B” may continue until shafts  60   a  ( FIG. 8 ) of bolts  60  contact bottom surface  16   b  of rafter  16 . Further movement of anchor clamp  24  in the direction of arrow “B” will cause bolts  60  to slide along slots  56  until shafts  60   a  also contact the lowermost region of slots  56  and further movement is halted. When this occurs, most if not all of apertures  50 ,  54  may be positioned above upper surface  16   a  of rafter  16 . The worker may then insert his or her safety system&#39;s connector  32  through one or both of apertures  54 , or through one or both of apertures  52 , or through hole  48  in middle wall  40 , or through hole  48  and one of the apertures  54 . Once connector  32  is so secured, the worker may let anchor clamp  24  go and anchor clamp  24  may slide downwardly back toward upper surface  16   a  of rafter  16  in the opposite direction to arrow “B”. The worker may additionally further tighten fasteners  58  to lock anchor clamp  24  in the position illustrated in  FIG. 9 . At this point, the worker is securely anchored to rafter  16  via anchor clamp  24 . Allowing some slack in the positioning of anchor clamp  24  may be helpful for absorbing shock if the safety anchor system actually has to be utilized to arrest a fall. 
     Disengaging the safety harness assembly (i.e., harness  28 , lanyard  30 , and connector  32 ) from anchor clamp  24  requires simply reversing the above-mentioned steps. Similarly, removing anchor clamp  24  from rafter  16 , if so desired, simply requires reversing the above-mentioned steps. 
       FIGS. 11-18  show a second embodiment of an anchor clamp in accordance with the present disclosure. This second embodiment of the anchor clamp is generally indicated in the following description and in the drawings by the reference number  144 . Anchor clamp  144  may comprise one or two planar members that may be generally rectangular in shape. Two substantially identical anchor clamps  144  and a plurality of bolts, that will be described hereafter, make up an anchor clamp assembly  145 . Assembly  145  may be used by a worker to secure a safety harness ( 28 ,  30 ,  32 — FIG. 1 ) to an anchor plate  19  ( FIG. 14 ) that is mounted on a beam  16  of truss  10 . Anchor plate  19  may be located in an off-peak position (i.e., not at the peak of the truss). Alternatively, anchor clamp assembly  145  may be engaged with an on peak anchor plate such as anchor plate  17  ( FIG. 1 or 14 ) or to any other suitable connector plate mounted on truss  10 . Anchor plate  17  may define a plurality of holes  17   a  therein to which anchor clamp assembly  145  may be engaged. The anchor clamp assembly  145  and safety harness ( 28 ,  30 ,  32 ) may be used to arrest a fall of a worker from the roof  10 . 
     Each planar member of anchor clamp  144  may be fabricated from steel and have an upper end  144   a , a lower end  144   b , a first side  144   c , a second side  144   d , an exterior surface  144   e , and an interior surface  144   f . A longitudinal axis “Z” may extend between upper end  144   a  and lower end  144   b . An elongate slot  146  may be defined in the planar member and slot  146  may extend between interior and exterior surfaces  144   e ,  144   f . Slot  146  may originate a short distance away from lower end  144   b  and extend longitudinally toward upper end  144   a . Slot  146  may be substantially parallel to longitudinal axis “Z” and have a first end  146   a  and a second end  146   b.    
     A first aperture  148  may be defined in the planar member a short distance downwardly from upper end  144   a  and at about a mid-point between first and second sides  144   c ,  144   d . First aperture  148  may extend between exterior and interior surfaces  144   e ,  144   f . A second aperture  150  may be defined a short distance downwardly from first aperture  148  and at about a mid-point between first and second sides  144   c ,  144   d . Second aperture  150  may extend between exterior and interior surfaces  144   e ,  144   f . First and second apertures  148 ,  150  may be longitudinally aligned with slot  146 . First and second apertures  148 ,  150  may be spaced about one and a half inches apart from each other. 
     An opening  152  may be defined in planar member  144 . Opening  152  may extend between exterior and interior surfaces  144   e ,  144   f  and may be located proximate a corner region of planar member  144 . When two planar members  144  are used in anchor assembly  145 , opening  152  defined in one planar member  144  may be aligned with opening  152  defined in the other planar member  1444 . A grab-line  154  ( FIGS. 14 and 17 ) may be threaded through each of the aligned openings  152 , thus securing grab-line  154  to each planar member  144 . Grab-line  154  may serve two purposes. Firstly, grab-line  154  may loosely secure the upper ends of the two planar members  144  together and, secondly, grab-line  154  may be easily grasped by a worker to pull planar members  144  upwardly and thereby move the planar members  144  from a retracted position ( FIGS. 14 and 15 ) to a protracted position ( FIG. 16 ). 
     If anchor clamp  144  is comprised of only a single planar member, then the fastener assembly may comprise slot  146 , second aperture  150 , a first bolt  160 , and a second bolt  161 . First bolt  160  ( FIG. 14 ) may be inserted through slot  146  and through a hole defined in an anchor plate  19  that is fixedly engaged with rafter  16  or into one of the sides  16   c ,  16   d  of rafter  16 . In some instances first bolt  160  may be positioned so as to extend below the lower surface  16   b  of rafter  16 . A second bolt  161  may be inserted into a second hole defined in anchor plate  19  or into one of the sides  16   c ,  16   d  of roof truss. First aperture  148  may comprise part of the connector assembly and may receive connector  32  from a worker&#39;s safety harness therethrough. 
     In other instances, anchor clamp  144  may comprise two planar members. A first one of the planar members comprises a first side wall of the anchor clamp  144  and is positioned adjacent a first surface of rafter  16 . A second one of the planar members comprises a second side wall of the anchor clamp  144  and is positioned adjacent a second surface of rafter  16 . The fastener assembly may be used to secure the first planar member (first side wall) and the second planar member (second side wall) together. The connector assembly may then be engaged with one or the other or both of the first planar member and the second planar member. The fastener assembly may comprise a first bolt  160  and a second bolt  161  and slots  146  and one of the apertures  148 ,  150  of the pair of substantially identical anchor clamps  144 . First bolt  160  may be inserted through slots  146  and be positioned below bottom surface  16   b  of rafter  16 . Second bolt  161  may be inserted through aligned second apertures  150  and be positioned above upper surface  16   a  of rafter  16 . A third bolt  162  and the first apertures  148  may comprise the connector assembly. The third bolt  162  may be inserted through the first apertures  148  and connector  32  may be passed around the shaft of third bolt  162 . Appropriate nuts and washers may be used to secure bolts  160 - 162  to anchor clamps  144 . Anchor clamp  144  may be engaged with anchor plate  19  at a mid-truss position. Alternatively, anchor clamp  144  may be engaged with plate  18  at an apex position. 
     The following description is directed to engagement of two planar members of anchor clamp  144  with anchor plate  19 . (Anchor plate  19  may be utilized to substantially prevent anchor clamp  144  from sliding down the rafter  16  to towards an end where the roof truss rafter  16  connects to the wall frame.) A first bolt  160  may be inserted through slot  146  on anchor clamp  144  and into a hole  19   a  defined in plate  19 . First bolt  160  may be tightened to a sufficient degree to secure anchor clamp  144  to plate  19  but not to lock anchor clamp  144  in a fixed orientation relative to plate  19 . When anchor clamp  144  is initially secured to plate  19 , anchor clamp  144  may hang downwardly from first bolt  160  because of gravity and first bolt  160  may be positioned adjacent second end  146   b  of slot  146  as shown in  FIG. 14 . This downwardly hanging position may be regarded as a retracted position because anchor clamp  144  does not extend above upper surface  16   a  of beam  16 . In this retracted position anchor clamp  144  may not be in a position useful to secure safety harness  28 ,  30 ,  32  thereto. 
     Anchor clamp  144  may be pivoted about first bolt  160  as indicated by arrow “C” in  FIG. 16  from the retracted position (shown in phantom) to the protracted position. (When anchor clamp  144  subsequently moves back into the retracted position, movement from the position shown in solid lines to the position shown in phantom lines in  FIG. 16  occurs by rotating anchor clamp  144  in the opposite direction.) 
     In the protracted position, a portion of anchor clamp  144 , including upper end  144   a  thereof, may extend above upper surface  16   a  of beam  16  and first bolt  160  may be located adjacent first end  146   a  of slot  146 . It should be noted that first bolt  160  is not disengaged from plate  19  in order to move anchor clamp  144  between the retracted and protracted positions. Instead, anchor clamp may rotate about an axis that extends along the shaft of first bolt  160 . Anchor clamp  144  may be restrained from a full range of rotation by the attached grab-line  154 . Grab-line  154  may contact an upper surface  16   a  of beam  16  as anchor clamp  144  rotates and will thus halt any continued rotational motion. 
     When anchor clamp  144  is in the protracted position, shown in  FIGS. 16 and 17 , both of the first and second apertures  148 ,  150  may be located above an uppermost end of anchor plate  19  and above upper surface  16   a  of beam  16 . Each of the anchor clamps  144  of anchor clamp assembly  145  may be engaged with the anchor plate  19  located on a different side of beam  16 . Both anchor clamps  144  may be rotated into the protracted position and a second bolt  161  may be passed through aligned first holes  148  in the two anchor clamps  144 . A third bolt  162  may be passed through aligned second holes  150  in the two anchor clamps  144 . Appropriate nuts and washers may secure bolts  161  and  162  in place. Once second and third bolts  161 ,  162  are securely engaged with anchor clamps  144 , anchor clamp assembly  145  may be ready to be used. 
     As with the first embodiment, a connector  32  (such as a carabiner) may be engaged around second bolt  161 , thereby securing lanyard  30  and safety harness  28  to anchor clamp assembly  145 . It will be understood that anchor clamps  144 , bolts  160 ,  161 ,  162  and connector  32  will be sized appropriately to be able to support the weight of a worker if they fall off the roof. 
     Referring now to  FIGS. 16A and 17A , anchor clamp assembly  145  may further include a crossover plate  200  that may be engaged with anchor clamp  144  and anchor plate  19 . Crossover plate  200  may be a generally rectangular strip of metal that defines two or more holes  202  therein.  FIGS. 16 and 17  show that bolt  160  may secure anchor clamps  144  to anchor plates  19  using nuts and washers.  FIGS. 16A and 17A  show that when crossover plate  200  is utilized in anchor clamp assembly  145 , the bolt  160  may be removed from anchor clamps  144 . Each washer is removed and may be replaced with one of the two connector plates  200 . Bolt  160  may then be inserted through the aligned holes  202  in connector plates  200  and the holes  19   a  in anchor plates  19  and slot  146  of each anchor clamp  144 . The nut may then be engaged with bolt  160 . A second bolt  160  may be inserted through the second hole  202  in connector plates  200 , through the holes  19   a  in anchor plates  19  and be secured in place using a second nut. Crossover plate  200  may thus be secured to anchor plates  19  by two bolts  160  and to anchor clamp  144  by one bolt  160 . Crossover plate  200  may serve the purpose of preventing anchor clamp  144  from disengaging from anchor plate  19  during an arrest event. 
     If a worker falls off the roof, the secured safety harness  28 ,  30 ,  32  may be used to arrest his or her fall. This is known as a fall arrest event and is illustrated in  FIG. 18 . During the fall arrest event, the third bolt  162  acts as a bearing bolt that abuttingly contacts upper surface  16   a  of beam  16  and serves as an stop or anchor for halting the motion of the falling worker. The rotational motion of anchor clamp  144  about first bolt  160  is shown in phantom and the arrested position is shown in solid in  FIG. 18 . After a fall arrest event the anchor clamp assembly  145  should be disengaged from truss  10  and a new anchor clamp assembly  145  should be engaged therewith. This is done because the assembly  145  may have been weakened by the fall arrest and may therefore be unable to adequately arrest a fall for a second time. 
     When a worker is finished working on the roof, anchor clamp assembly  145  must either be removed from truss  10  or be moved to a position where it no longer protrudes above an uppermost surface of any planar sheets  20 . Anchor clamp assembly  145  is designed to remain engaged with truss  10  at all times. In order to ensure that assembly  145  does not protrude above planar sheets  20 , anchor clamps  144  may be moved into the retracted position. In order to do this the second and third bolts  161 ,  162  may be removed from first and second apertures  148 ,  150 , respectively, and anchor clamps  144  may be rotated downwardly to the retracted position shown in  FIG. 14 . Second and third bolts  161 ,  162  may then be re-engaged with anchor clamps  144  when in this retracted position by passing them through the respective aligned holes  148 ,  150 . Alternatively, as illustrated herein, second and third bolts  161 ,  162  may not be reengaged with anchor clamps  144 . When it is later desired to use anchor clamp assembly  145  once again, anchor clamps  144  will be rotated back into the protracted position and new bolts  161 ,  162  will be utilized to secure the two anchor clamps  144  together. In the retracted position, the anchor clamps  144  may remain in an inaccessible position below the roof deck. When in the protracted position, the worker may access the connection point (bolt  161 ) for securement of the safety lanyard  30  thereto. Between uses, the roof opening  24  ( FIG. 1 ) may be covered with a removable flashing of sheet metal or other weather-resistant material. This flashing or cover  34  is shown in  FIG. 1 . When cover  34  is removed to expose hole  22  in the roof  20 , anchor clamp assembly  145  is once again accessible through that hole  22 . 
     Anchor clamp assembly  145  should be fully inspected before engagement of safety lanyard  30  therewith, particularly if some time has passed between the engagement of anchor clamp assembly  145  on truss  10  and the securement of safety harness  28 ,  30 ,  32  thereto. This situation may occur when anchor clamp assembly  145  is engaged when the roof is initially constructed and must then be accessed several year later when a replacement roof is installed. The concealment of anchor clamp assembly  145  with cover  34  between uses may be a vital safety matter as concealment effectively prevents the use of anchor clamp assembly  145  by unqualified persons who have not been trained in the correct engagement and/or use of safety harnesses. Untrained individuals could be seriously harmed if they attempt to anchor themselves and accidentally do not follow the procedures correctly. 
     Using two anchor clamps  144  as anchor clamp assembly  145  instead of only one anchor clamp  144  may be safer for arresting a fall. Using a single anchor clamp  144  may be possible although this is less desirable. In this latter instance, a connector  32  may be secured directly to one of first or second holes  148 ,  150  of a single anchor clamp  144  that may be engaged with anchor plate  19  by way of a bolt  160 . As indicated above, this is not the preferred manner of engaging a safety lanyard  30  to beam  16 . 
       FIGS. 19-27  show that an anchor clamp assembly in accordance with the present disclosure may comprise anchor clamp  144  along with a protector plate that may be selectively positioned on upper surface  16   a  of rafter or chord  16  between the plate members of anchor clamp  144 . The protector plate may be provided to protect the upper surface  16   a  of rafter  16  from potential damage when the anchor clamp is used to arrest a worker&#39;s fall. The protector plate may prevent bolts  161 ,  162 , for example, from cutting into upper surface  16   a  during a fall arrest event. 
       FIGS. 19-21  illustrate a first embodiment of the protector plate that is generally indicated at  300 .  FIGS. 22-24  illustrate a second embodiment of the protector plate, generally indicated at  400 .  FIGS. 25-27  illustrate a third embodiment of the protector plate, generally indicated at  500 . It will be understood that any of the protector plates  300 ,  400 ,  500  may be used with anchor clamp  144 .  FIGS. 19, 22, and 25  show the various embodiments of the protector plate  300 ,  400 , and  500  used with anchor clamp  144 . (It will be understood that in other instances, protector plates  300 ,  400 ,  500  may also be used with anchor clamp  24  and at one bolt that passes through apertures  50 ,  54 .) 
     Referring to  FIGS. 19-21 , protector plate  300  may comprise a generally open U-shaped member having a first surface  300   a , a second surface  300   b , a first end  300   c , a second end  300   d , a first side edge  300   e , and a second side edge  300   f . Protector plate may comprise five legs  302   a ,  402   b ,  302   c ,  302   d , and  302   e  that are each oriented at an angle relative to the adjacent legs so that the five legs each are located in slightly different planes. First leg  302   a  may extend from first end  300   c  to a first corner  300   g ; second leg  402   b  extends from first corner  300   g  to third leg  302   c , fourth leg  302   d  extends from third leg  302   c  and meets fifth leg  302   e  at a second corner  300   h . First leg  302   a  and second leg  402   b  may be oriented at an angle α relative to each other and fourth leg  302   d  and fifth leg  302   e  may be oriented at an angle  11  relative to each other. The angles α and β may be obtuse angles that may be of generally the same size or of different sizes. The angles α and β help ensure that first leg  302   a  and fifth leg  302   e  are space a distance away from upper surface  16   a  of roof rafter  16  so that a worker can easily engage a connector  32  therewith. 
     It will be understood that protector plate  300  may include fewer than five legs  302   a - 302   e  or more than five legs. For instance, protector plate  300  may include only three legs, where the middle leg is oriented so as to lay flat upon upper surface  16   a  of roof rafter  16  and the two end legs angle upwardly and outwardly from the middle leg and therefrom from upper surface  16   a  of roof rafter  16 . Protector plate  300  may even comprise only two legs; one that lays on upper surface  16   a  and one that angles outwardly therefrom. 
     A cylindrical member  304  may be welded to approximately a middle region of third leg  302   c  and on the first surface  300   a  thereof. Cylindrical member  304  may extend from first side edge  300   e  to second side edge  300   f  of protector plate  300  and may define a bore  304   a  therethrough. Bore  304   a  may extend from first side edge  300   e  to second side edge  300   f  of protector plate. Bore  304   a  may be shaped and sized so that the shaft of bolt  162 , for example, may be inserted therethrough when anchor clamp  144  is to be secured to rafter  16 . Inserting bolt  162  through bore  304   a  effectively may secure protector plate  300  between anchor clamps  144 . The first anchor clamp  144  may form a first side wall that extends along a first side surface  16   c  of roof rafter  16 ; the second anchor clamp  144  may form a second side wall that extends along a second side surface  16   d  of roof rafter  16 ; and protector plate  300  may form a middle wall that extends along upper surface  16   a  of roof rafter  16 . 
     Protector plate  300  may also define a first aperture  306  in first leg  302   a  and a second aperture  308  in fifth leg  302   e . First and second apertures  306 ,  308  may extend from first surface  300   a  through to second surface  300   b . First and second apertures  306 ,  308  may be shaped and sized to selectively receive connector  32  from a worker&#39;s safety harness therethrough instead of having the connector  32  engage with bolt  162 . 
     Protector plate  300  may further define one or more holes  310  in second leg  402   b  and fourth leg  302   d . Holes  310  may extend from first surface  300   a  through to second surface  300   b  and may be shaped and sized to receive a nail or other fastener therethrough. The nails/fasteners may be utilized in order to secure protector plate  300  to upper surface  16   a  of rafter  16 . When protector plate  300  is so secured to rafter  16  by nails, protector plate  300  may provide static tethering for the worker and additionally aids in helping to decelerate the speed of a worker who may fall while tethered to anchor clamp  144 . It should be noted that when one or more nails  312  is engaged with protector plate  300 , second leg  302   b , third leg  302   c  and fourth leg  302   d  may all be caused to be oriented along the same plane. 
       FIG. 21  shows protector plate  300  secured to rafter  16  by nails  312  that extend at least partially through holes  310  in plate  300 . Bolt  162  of anchor clamp  144  may be passed through bore  304   a  of cylindrical member  304 , thereby securing protector plate  300 , and anchor clamp  144  together. Connector  32  may be engaged with protector plate  300  by inserting part of connector  32  through aperture  306  or through aperture  308 . 
     Protector plate  400  is illustrated in  FIGS. 22-24 . Protector plate  400  may be substantially identical to protector plate  400  except that the holes  310  may be omitted therefrom. Protector plate  400  may be a generally open U-shaped member having a first surface  400   a , a second surface  400   b , a first end  400   c , a second end  400   d , a first side edge  400   e , and a second side edge  400   f . Protector plate may comprise five legs  402   a ,  402   b ,  402   c ,  402   d , and  402   e  that are each oriented at an angle relative to the adjacent legs so that the five legs each are located in slightly different planes. First leg  402   a  may extend from first end  400   c  to a first corner  400   g ; second leg  402   b  extends from first corner  400   g  to third leg  402   c , fourth leg  402   d  extends from third leg  402   c  and meets fifth leg  402   e  at a second corner  400   h . First leg  402   a  and second leg  402   b  may be oriented at an angle α relative to each other and fourth leg  402   d  and fifth leg  402   e  may be oriented at an angle β relative to each other. The angles α and β may be obtuse angles that may be of generally the same size or of different sizes. The angles α and β help ensure that first leg  402   a  and fifth leg  402   e  are space a distance away from upper surface  16   a  of roof rafter  16  so that a worker can easily engage a connector  32  therewith. 
     It will be understood that protector plate  400  may include fewer than five legs  402   a - 402   e  or more than five legs. For instance, protector plate  400  may include only three legs, where the middle leg is oriented so as to lay flat upon upper surface  16   a  of roof rafter  16  and the two end legs angle upwardly and outwardly from the middle leg and therefrom from upper surface  16   a  of roof rafter  16 . Protector plate  400  may even comprise only two legs; one that lays on upper surface  16   a  and one that angles outwardly therefrom. 
     A cylindrical member  404  may be welded to approximately a middle region of third leg  402   c  and on the first surface  400   a  thereof. Cylindrical member  404  may extend from first side edge  400   e  to second side edge  400   f  of protector plate  400  and may define a bore  404   a  therethrough. Bore  404   a  may extend from first side edge  400   e  to second side edge  400   f  of protector plate. Bore  404   a  may be shaped and sized so that the shaft of bolt  162 , for example, may be inserted therethrough when anchor clamp  144  is to be secured to rafter  16 . Inserting bolt  162  through bore  404   a  effectively may secure protector plate  400  between anchor clamps  144 . The first anchor clamp  144  may form a first side wall that extends along a first side surface  16   c  of roof rafter  16 ; the second anchor clamp  144  may form a second side wall that extends along a second side surface  16   d  of roof rafter  16 ; and protector plate  400  may form a middle wall that extends along upper surface  16   a  of roof rafter  16 . 
     Protector plate  400  may also define a first aperture  406  in first leg  402   a  and a second aperture  408  in fifth leg  402   e . First and second apertures  406 ,  408  may extend from first surface  400   a  through to second surface  400   b . First and second apertures  406 ,  408  may be shaped and sized to selectively receive connector  32  from a worker&#39;s safety harness therethrough instead of having the connector  32  engage with bolt  162 . 
       FIG. 24  shows protector plate  400  placed on upper surface  16   a  of rafter  16 . In this instance, only third leg  402   c  contacts upper surface  16   a  and the first and second legs  402   a ,  402   b  and the fourth and fifth legs  402   d  and  402   e  angle upwardly away from upper surface  16   a  in opposite directions. Bolt  162  of anchor clamp  144  may be passed through bore  404   a  of cylindrical member  404 , thereby securing protector plate  400 , and anchor clamps  144  together. Connector  32  may be engaged with protector plate  400  by passing at least a portion of connector  32  through one of the apertures  406 ,  408  as previously described herein. 
       FIGS. 25-27  show protector plate  500  that may be used with anchor clamp  144 . Protector plate  500  may be substantially identical to protector plate  300  except that instead of providing a generally open U-shaped member having a cylindrical member approximately midway between first end  500   c  and second end  500   d ; the metal of protector plate  500  is bent back upon itself to form a passageway for the shaft of bolt  162 . Protector plate  500  may have a first surface  500   a , a second surface  500   b , a first end  500   c , a second end  500   d , a first side edge  500   e , and a second side edge  500   f . Protector plate  500  is folded or bent back upon itself so that a first region of second surface  500   b  proximate first end  500   c  abuts a second region of second surface  500   b  proximate second end  500   d . An arcuate bend  500   g  is formed approximately midway between first end  500   c  and second end  500   d . Portions of the second surface  500   b  on either side of bend  500   g  do not abut each other but are spaced a distance apart such that an opening  500   h  is defined therebetween. Opening  500   h  may of a shape and size that will permit the shaft of bolt  162  to pass therethrough. An aperture  508  similar to apertures  306 ,  308  may be defined a short distance inwardly from each of the opposing ends  500   c ,  500   d . When protector plate  500  is bent back upon itself, the apertures  508 ,  508  may be aligned and form a single opening through plate  500 . Similarly, a hole  510  sized to receive a nail or other fastener may extend between the first and second surfaces  500   a ,  500   b  and be positioned a short distance further away from first end  500   a  or second end  500   b  than aperture  508 . Again, when protector plate  500  is bent back upon itself, the two holes  510  may be aligned to form a single hole through which a nail or other fastener may be inserted.  FIG. 25  shows that bolt  162  may be received through opening  500   h  to secure anchor clamp  144  and protector plate  500  together. A nail or other fastener may be received through openings  510  if desired. Connector  32  may be secured to protector plate  500  by passing at least a portion thereof through aperture  506 ,  508 . 
       FIG. 28  illustrates a situation where protector plate  500  may be used in conjunction with anchor clamp  24  instead of with anchor clamp  144 . In this particular instance protector plate  500  may be engaged with middle wall  40  of anchor clamp  24  such that a first arm  501  of protector plate  500  is located in contact with exterior surface  40   a  of middle wall  40  and a second arm  503  of protector plate  400  is in contact with interior surface  40   b  thereof. Second end  40   f  of middle wall  40  may be seated in the opening  500   h  defined by protector plate  500 . The first and second arms  501 ,  503  may be forced a distance apart from each other such that a gap  505  is created between them. Gap  505  may be of a size that is generally equivalent to the thickness of middle wall  40 ; where the thickness is measured between exterior and interior surfaces  40   a ,  40   b . The end regions of the arms  501 ,  503  may extend for a distance outwardly beyond first end  40   e  of middle wall  40  and the connector  32  may be passed through the aligned apertures  508 ,  508  defined in the first and second arms  501 ,  503 . 
     Although not illustrated herein, it will be understood that a further embodiment of the protector plate may be substantially identical to protector plate  500  except that the holes  510  may be omitted therefrom. 
     In the foregoing description, certain terms have been used for brevity, clarity, and understanding. No unnecessary limitations may be to be implied therefrom beyond the requirement of the prior art because such terms may be used for descriptive purposes and may be intended to be broadly construed. 
     Moreover, the description and illustration set out herein may be an example and the invention is not limited to the exact details shown or described.