Patent Publication Number: US-6220577-B1

Title: Temporary guard railing

Description:
This application claims priority under 35 U.S.C. Section 119(e) to a provisional application filed Jul. 17, 1998 bearing Ser. No. 60/093,211. 
    
    
     TECHNICAL FIELD 
     This invention relates to safety devices and more specifically to temporary guard railings used during construction of buildings. 
     BACKGROUND-DESCRIPTION OF PRIOR ART 
     In the construction of multiple-story buildings, both commercial and residential, considerable risk is present to craftsmen and others at the building site during the main stages of construction. Specifically, there is considerable risk that workers may accidentally fall from an upper story and sustain a serious injury or even death. These concerns are especially high until exterior walls are installed around elevated floors and until a permanent bannister or railing system is installed on balconies, staircases and the like. 
     Regulations of the Occupational, Safety and Health Administration (OSHA), require the use of safety protection at locations where a risk is present that persons may fall. To satisfy OSHA regulations, safety protection in the form of temporary guard rails must exceed certain minimum lateral load requirements without experiencing permanent deformation or component failure. 
     Numerous temporary guard rails have been designed to address these safety concerns. Over time, designs for guard rails have improved structurally. However, some building designs have features which require railings to angled in different directions and/or orientations. Especially for these situations, installation of guard rails has proven cumbersome and requires additional time because of the changes in vertical height and horizontal direction. 
     Typical of the prior art is U.S. Pat. No. 3,776,521 issued to Weinert. Weinert discloses a portable safety railing for use in a horizontal plane which can be connected lengthwise in series or connected at right angles. 
     U.S. Pat. No. 5,683,074 issued to Purvis et al., discloses a guard rail system which incorporates a plurality of upright stanchions. Attached to the stanchions are support collars which support side rails and also permit the rails to be rotated 360 degrees about the stanchion. Once the proper angle is obtained, the support collars are fixed in position by use of wing nuts. The wing nuts are also used along with an incline adapter bracket to angle side rails vertically. Finally, Purvis et al., teaches the use of adjusting side rail length by the use of a telescopic means. One concern of this system is that failure of a wing nut can compromise the integrity of the guard rail. 
     SUMMARY OF THE INVENTION 
     The present invention provides a temporary guard rail assembly designed so that it can be quickly installed for a variety of situations and provide the necessary guard rail function. The safety stanchion post assembly meets OSHA requirements and is adapted for building construction use as a temporary rail system installed when framing of a building is finished and removed as the installation of walls and permanent railings near completion. 
     Accordingly, the present invention is directed to a safety stanchion post assembly which comprises: a) a flat mounting plate fabricated to rest on a support surface or flooring; b) an upright post fixed in a vertical relationship on the mounting plate and having a pair of brackets permanently attached at different distances from the mounting plate; and c) means for attaching the mounting plate upon the support surface. 
     At least two stanchion post assemblies are used in series to support an upper and a lower rail system. Each rail system comprises a plurality of rails coupled in series to adjacent rails on either end by a coupling which can be described as a flex joint. In this specification, I use flex joint and coupling interchangeably and both have the same meaning. My coupling permits flexibility in allowing each rail to be orientated in a variety of directions respective to an adjacent rail. An adjacent rail is defined as a rail which is capable of being coupled to the rail. Each rail system will be supported by a respective bracket on each stanchion post assembly. Each rail comprises an outer elongated member and an inner elongated member which is capable of telescopically extending away from the outer member resulting in a rail whose length can be varied. 
     The unique flex joint is coupled on one end to the outer member of one rail and coupled on the other end to the inner member of an adjacent rail. 
     Preferably, the upright post or stanchion has two brackets permanently fixed to the post at vertical distances of 42 inches and 21.5 inches from the base of the mounting plate. The brackets can be L-shaped or U-shaped. However, U-shaped is more desirable since it can be secured to the side of the upright post more securely because of a greater available weld area. Also, the distal side of either the U or L shape bracket is preferably longer than the outside diameter of the rail to help maintain the rail on the bracket. 
     The means for permanently affixing the brackets is by welding to the stanchions. 
     Each bracket has a hole which is on the bracket wall affixed to the stanchion. A pair of holes are made transversely through the sidewall of the post so that the post holes are in line with the bracket hole and the distal side of a respective bracket. A fastener in the form of a set screw threadably engages at least one of the holes and is partially positioned between the post holes. Preferably, the post hole distal from each respective bracket is larger than the head of the set screw or fastener. This is so that as each rail is frictionally engaged by a set screw, the head will have its position within the post or no more than flush with the post. In this way, persons walking close to each post will not have their clothing snag on a protruding screw head. Also, there is less of a chance that passers-by may wish to try unscrewing the set screws when they are out of sight. 
     When a rail is placed upon a pair of brackets, the fasteners are then used to secure the rail in place. Sufficient torque is used upon the fasteners to ensure the rails remain secure. 
     The bracket design insures that even if a fastener should fail, the rail system will not be displaced off of its position on each bracket. 
     The brackets can also be fitted with a removably attached flat plate or pin positioned above the rail to enclose the rail within the bracket thereby preventing the rail from being inadvertently lifted out from supportable engagement with the bracket. However, because of the weight of the rail members, it is believed this enclosure means is not necessary to the overall function of the invention. 
     The mounting-plate has four holes defined therein along the peripheral corner of the plate and is preferably spaced in relationship to one another. The plate is fastened to the support surface by lag screws that extend through the openings in the mounting plate. 
     The rails can be made of various lengths and each have a slidable inner member that permits each rail to have an adjustable length. This type of variable length can be used to close gaps in order to meet the OSHA required maximum allowable opening of three inches. Although diameters can vary, my invention utilizes a 1½ inch diameter for the outer rail member and a 1¼ inch diameter for the inner member. 
     The rails are preferably made of a high strength material such as steel. The rail configuration is tubular and can be in either in the form of a round pipe or the more preferred square pipe configuration. For purposes of this specification I will use the term circumference to define the outer or exterior surface distance for square pipe as it is commonly used for round pipe. 
     Although rails can be of varying length, for my invention I preferably use three rail lengths: 1) a three foot length which can be extended up to five feet; 2) a five foot length which can be extended up to nine feet; and 3) an eight foot length which can be extended up to fifteen feet. 
     The inner member of the rail has a temporary attachment means such as a pole clip that allows the inner member to lock in place with the overlying outer rail member. Each outer rail member has an opening to allow for the pole clip to extend through in order to temporarily fasten the inner member to the outer member. The use of such a locking device is only for increasing the ease by which the rails are handled and transported to and from the site location. Without such a locking device, the inner member can slide out away from the outer member at an undesired time and make rail transport more difficult to manage. 
     The inner member, in its retracted and locked position, has its distal end protruding approximately three inches from the outer rail member. The protruding section of the inner member is necessary for proper slidable engagement to the flex joint as will be discussed below. 
     The flex joint or coupling allows for the interconnecting of rails and affords maximum flexibility to allow the rail system to adjust to any stairway configuration or floor perimeter. The flex joint couples adjacent rail members. 
     The flex joint or coupling comprises two rail coupling sections which are connected to a directional means. 
     The flex joint has a first rail coupling section which has a distal end having an inside diameter which is large enough for slidably receiving the distal end of an inner rail member. The second rail coupling section has a distal end having an outside diameter which is small enough to be slidably received within the distal end of an outer rail member. Each rail coupling section of the flex joint is a substantially hollow member. 
     One embodiment of the directional means incorporates the use of a heavy duty spring. The ends of the spring are attached to metal pins transversely positioned in the interior of each rail coupling section. 
     An alternative embodiment of the directional means incorporates the use of a rotatable hinge. The hinge is connected by a hinge pin which permits movement in one plane. However, the ends of the directional means distal from the hinge are each rotatably connected to a respective rail coupling section. The hinge can therefore be rotated into a desired orientation and then displaced upon the desired plane to achieve the desired position. 
     The purpose of the flex joint is two-fold. First, it provides a quick slidable attachment means to ends of adjacent rails. Second, the flex joint permits the overall rail system to be utilized in varying configurations and is not limited to a horizontal application. 
     The high tension spring embodiment insures a secure rail, even when acute angles are required for the rail system design. However, either embodiment can be additionally secured to rail members on either side by the use of set screws or the like. 
     Having described the main parts of my invention, the method of attachment will now be discussed. 
     The stanchions are first positioned and secured to the support surface or flooring through the use of fasteners such as lag screws or the like. Since the brackets are welded to the upright post, proper orientation of each stanchion is necessary to insure that the brackets are aligned with a similar reference; that reference is usually the edge of the flooring. 
     It is preferred to use two stanchions to support each upper and lower rail. Each rail is positioned and lowered into a respective bracket. Once the brackets support the weight of a rail, a securing means such as set screws located in the stanchion are used to frictionally engage the rail between the set screw on one side and the distal side of the bracket on the other. Because of the stanchion placement relative to one another, it may be necessary to extend the inner rail member before securing it to the bracket with a set screw. Once both the inner and outer rail members are secured within the brackets by the set screws, the flex joint can be slidably coupled to a rail end and then coupled to an adjoining rail end. 
     Before the flex joint is attached to adjacent rails, the inner and outer members of one rail are secured to brackets while usually only one member of the adjoining rail is secured. The flex joint is slidably coupled to the secured rail and then the unsecured rail is slidably moved as necessary to become coupled with the flex joint prior to the unsecured rail member being secured to the bracket with a set screw. From this it is readily apparent that aside from the slidable engagement, no other attachment means is utilized for securing the flex joint to the adjoining rail ends. 
     As described above, the flex joint has one end for sliding into an adjacent outer rail member while the other end of the flex joint slides over an adjacent inner rail member. It is readily apparent that the flex joint can also be made having ends of similar dimension so long as the ends of the inner and outer rail members have compatible similar dimension ends or exterior circumference. As an example, a flex joint can be made having ends which are designed to slide over the circumference of an inner rail member. The end of each outer rail member therefore, can be modified to have the same circumference as an inner rail member. This can be accomplished by securing a short-length attachment to the outer rail member which has the same circumference as the inner member. 
     These and other features and advantages of the present invention will become apparent to those skilled in the art upon reading the following detailed description in conjunction with the drawings provided. 
    
    
     DESCRIPTION OF THE DRAWINGS 
     FIG. 1 illustrates a perspective view of a safety rail system of the present invention. 
     FIG. 2 illustrates a cut-away view of a first embodiment of the flex joint. 
     FIG. 3 illustrates a cut-away view of a second embodiment of the flex joint. 
     FIG. 4 is a cut-away view illustrating the use of a pole-lock pin. 
     FIG. 5 illustrates the locking means for attaching rails to respective brackets. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIG. 1 provides a perspective view of my temporary guard railing  10 . Each rail has a substantially square circumference and comprises two elongated sections; an outer rail  16  and an inner rail  18  partially disposed within outer rail  16 . Inner rail  18  is a slidable member but in its retracted position, will still be partially exposed. Therefore, one rail will have two ends of varying outer circumference: a first end having the circumference of outer rail  16  and the second end having the circumference of inner rail  18 . 
     Outer rail  16  has an aperture  26  while inner rail has one aperture (not indicated). As can be best shown in FIG. 4, a pole-clip  58  is attached to the inner wall of inner rail  18  and aligned so that the cylindrical stud  28  located at one end of pole-clip  58  can pass through the inner rail aperture and come into frictional contact with outer rail  16  due to the outward bias of pole-clip  58 . Aperture  26  and stud  28  can be aligned with each other. When this happens, stud  28  will extend into aperture  26  thereby precluding further movement of inner rail  18  relative to outer rail  16 . A downward displacement force is thereafter required to force stud  28  away from outer wall  16  and permit inner rail  18  to become slidable. 
     My invention also utilizes a plurality of stanchions  11  which are necessary for supporting each of the rails. Each stanchion  11  comprises an upright post  12 , a base  14  attached to the bottom of post  12 , and a pair of brackets  20 . 
     Preferably, the bottom of post  12  is positioned on top of the center portion of base  14 . A plurality of holes  60  extend through base  14 . Lag screws  62  are then used to attach base  14  to the flooring or supporting surface. 
     Brackets  20  are substantially U-shaped and are permanently attached to the side of post  12 . Both brackets  20  are positioned on the same side of post  12 , one above the other. The distance between both brackets is preset to conform with the desired spacing between the upper rail system and the lower rail system. 
     Each bracket  20  has a hole which is aligned with a pair of holes  22  found on post  12 . All three holes have a common axis of symmetry which will permit screw  24  to be inserted as shown in FIG.  1  and FIG. 4, threadably engage and partially extend into the space between the opposing faces of bracket  20 . 
     A coupling  30  having a first embodiment of the directional means is shown in FIG.  2  and is used to connect adjacent rail members. Flex joint  30  is comprised of a pair of hollow members  33  and  34  having their respective ends  54  and  56  adjacent to one another. It can be seen that the distal end  36  of hollow member  33  has a larger outside diameter than the distal end  32  of hollow member  34 . The different sized ends of flex joint  30  is necessary to properly couple to adjacent rail ends as will be discussed later. 
     A spring  42  is connects to hollow members  33  and  34 . One end of spring  42  is hook-shaped  44  and secured to a transverse pin  38  which extends across the inside diameter of hollow member  34 . The other end of spring  42  is also hook-shaped  46  and secured to the end of a threaded screw member  52 . Screw member  52  is passed through an aperture located on transverse pin  48  and is threadably engaged on the other side of pin  48  to a nut  50 . The tension of spring  42  can be adjusted by rotation of nut  50 . 
     An alternative flex joint  130  having a second embodiment of the directional means is shown in FIG.  3 . Flex joint  130  is comprised of a pair of members  133  and  134  having their respective ends  154  and  156  adjacent to one another. It can be seen that the distal end  136  of hollow member  133  has a larger outside diameter than the distal end  132  of hollow member  134 . As with flex joint  30 , the different sized ends of flex joint  130  are necessary to properly couple to adjacent rail ends. 
     Instead of using a spring for the directional means, flex joint  130  utilizes a rotatable hinge. Hinge members  143  and  147  are coupled to each other by hinge pin  139 . Hinge members  143  and  147  can move relative to one another along one plane. The portion of hinge members  143  and  147  which extend into respective members  134  and  133  are cylindrical so that they are capable of rotation within. Member  134  has a plate or mounting pin  145  permanently attached to the inner wall of member  134 . Plate  145  has a hole for passage of the stem of screw  153 . Similarly, member  133  has a plate or mounting pin  149  permanently attached to the inner wall of member  133 . Plate  149  has a hole for passage of the stem of screw  151 . The ends of hinge members  143  and  147  distal from pin  139  have female threads for threadable engagement with respective screws  153  and  151 . Once threadably engaged to screws  151  and  153 , hinge members  147  and  143  are rotatable within respective members  133  and  134  and, in combination with their connection to hinge pin  139 , permit flex joint  130  to be positioned in various orientations for receiving adjacent rail members. 
     With the components of my temporary guard rail having been adequately described, its assembly will now be explained. 
     Initially, stanchions  11  are first positioned and secured to the support surface or flooring through the use of lag screws  62  or the like. Proper orientation of each stanchion  11  is necessary to insure that each rail system can be supported by a respective set of brackets  20 , for example, lower brackets to support a lower rail system which comprises a series of rails coupled by flex joints  30 . 
     Also, the rails used in my invention can be of various lengths with each rail capable of being extended an additional length. It is therefore not necessary nor envisioned by my invention to require the same spacing between each stanchion  11 . 
     Once stanchions  11  have been secured to the flooring, a rail will be placed upon a pair of adjacent brackets  20 . Depending upon the spacing between each stanchion  11  and the positioning of the flex joint  30 , a rail may need to be extended. In this case, stud  28  will require depressing so that inner rail  18  can be slidably extended from outer rail  16 . Once the desired length is obtained, screws  24 , located on each respective bracket  20 , are used to frictionally engage the rail between screw  24  and the interior wall  21  of bracket  20  as shown in FIG.  5 . It is preferred that screw  24  of one bracket  20  is in engagement with outer rail  16  while screw  24  of the other bracket supporting the rail is in engagement with inner rail  18 . In this configuration, the rail can no longer be extended because the inner and outer rails are each secured. 
     Flex joint  30  is then slidably mounted upon the distal end of the rail. Since the ends of each rail have one end of the circumference of outer rail  16  and the other of inner rail  18 , flex joint must be aligned correctly in order to couple. Therefore, distal end  36  will be coupled to one rail by sliding over inner rail  18 . The other distal end  32  will be coupled to the adjacent rail by being inserted into outer rail  16 . 
     Flex joint  30  will remain coupled to the adjacent rails so long as the outer rail  16  and inner rail  18  coupled to flex joint  30  are respectively secured to brackets  20  by screws  24 . 
     Since flex joint  30  is a spring, it can be oriented into various directions and angles. FIG. 1 illustrates the use of flex joint  30  for a change in horizontal and vertical directions. Because a spring is used as a directional means, angles can approach close to 180 degrees in a single plane thereby allowing a wide range of application. 
     Other features and advantages of the invention will become apparent to those skilled in the art and various modes are contemplated as being within the scope of the following claims particularly pointing out and distinctly claiming the subject matter which is regarded as the invention.