Patent Publication Number: US-2019178034-A1

Title: Vertical ladder

Description:
FIELD OF THE INVENTION 
     This invention relates generally to improvements in vertical ladders. 
     BACKGROUND OF THE INVENTION 
     Vertical ladders of various configurations exist. For example, Babaylova, WO (2013/105880) discloses a vertical ladder having four stiles and horizontal rungs spanning therebetween which pivotally engaged half treads especially suited for climbing vertically in confined spaces. 
     Lapeyre, U.S. Pat. No. 4,199,040 discloses an angled shipboard ladder having side handrails a central tread support 10 and half treads 116 extending therebetween which is designed to be safe and comfortable to use. 
     Lapeyre U.S. Pat. No. 4,509,617 referred to hereinafter as Lapeyre 617 discloses an angled stair having three parallel stringers and half treads respectively extending therebetween which does not obstruct the user&#39;s foot and proceeding to the next tread. 
     Wilson, US (2016/0017657) discloses a plurality of interconnected ladder segments having rungs which can be pivotally collapsed. 
     However, it would be ideal for a vertical ladder that allows one to climb vertically without holding on such as when carrying equipment with one&#39;s hands. 
     Furthermore, it would be ideal for a vertical ladder to allow a one to climb the ladder with a better and stable climbing stance. 
     Furthermore, it would be ideal for a vertical ladder having an arrangement of rungs and rails which can be ergonomically held for supporting oneself or for counterbalance. 
     The present invention seeks to provide an improved vertical ladder, which will overcome or substantially ameliorate at least some of the deficiencies of the prior art, or to at least provide an alternative. 
     It is to be understood that, if any prior art information is referred to herein, such reference does not constitute an admission that the information forms part of the common general knowledge in the art, in Australia or any other country. 
     SUMMARY OF THE DISCLOSURE 
     There is provided herein a vertical ladder comprising two side stiles and at least one front vertical rail. The at least one front vertical rail is located further in from the sides of the ladder as compared to the stiles. 
     The ladder comprises two sets of half treads supported in vertical alignment by each respective stile. A plurality of horizontal rung members are connected between at least one rail and a respective half tread or stile. 
     Furthermore, each horizontal rung member only has a front straight bar portion and an orthogonal side straight bar portion. In other words, each straight bar terminates orthogonally at the at least one rail (i.e. at a T-junction) at one end of the rung, thereby allowing a vertical grab rail portion at an adjacent opposite side of the at least one rail for gripping, including for counterbalance. The side straight bar portion terminates at the other side of the rung at a respective half tread or stile. 
     Furthermore, the rung members are alternately arranged vertically such that vertically adjacent side straight bars and respective half treads are located at opposite side stiles. In other words, opposite half treads are vertically staggered. 
     As such, a user may ascend the ladder by stepping sideways onto the inward facing half treads. The vertically staggered arrangement thereof may allow the user to shift the user&#39;s centre of gravity from side to side between the opposing half treads, thereby being able to climb the ladder without holding on. 
     Furthermore, the rung and rail arrangement allows for ergonomic holding and counterbalancing. 
     Specifically, the user may pull downwardly on the rungs, either at the front or side straight bar portions thereof. The spacing of the front straight bar portions matches the spacing between vertically adjacent half treads such that, for each half step, the user may pull a corresponding straight bar portion. 
     Furthermore, the vertical grab rail portions allowed by the T-junction connection of the rail and rungs allows the user to counterbalance sideways in the manner shown in  FIG. 5  when stepping up or down. For example, when stepping up with the right foot whilst bearing one&#39;s bodyweight with the left foot as shown in  FIG. 5 , the centre of gravity shifts to the right which is counterbalance by the left-hand holding onto the left hand vertical grab rail portion. 
     Furthermore, the length of each grab rail portion is twice that of between vertically adjacent half treads. As such, and with reference to  FIG. 5 , the length of the left-hand grab rail portion being held by the user has the same length as that of the spacing between vertically adjacent half treads of the right stile such that, as the user steps up with the right hand foot, the user may grab the grab rail portion along the length of the grab rail portion which matches the travel distance of the right foot. 
     Furthermore, vertically adjacent grab rail portions are oppositely located and overlap by the same distance as between vertically adjacent half treads such that each vertically adjacent grab rail portion is located for gripping for each corresponding half tread. 
     Embodiments of the present vertical ladder may comprise one or two front rails both of which expose conveniently located rails and vertical grab rail portions for counterbalance in the manner described above. 
     In embodiments, the stiles may be connected together using connectors which may allow the ends of the stiles to bear directly against each other to enhance weight-bearing resilience of interconnected stiles. 
     In embodiments, the side straight bar portions may not connect to the respective stiles directly but connect rather to the half tread which is in turn connected to the side stiles. This configuration locates the side straight bar portions closer in within reach and may further allow the front of the foot to step partially on the side straight bar portion in the manner shown in  FIG. 3 . 
     In embodiments, the front row may comprise an extrusion defining a vertical track therealong for a fall arrest device. 
     According to one aspect, there is provided a vertical ladder comprising two side stiles and at least one front vertical rail, the at least one front vertical rail being located further in from sides of the ladder as compared to the stiles, two sets of half treads supported in vertical alignment by each respective stile, a plurality of horizontal rung members connected between the at least one rail and at least one of a respective half tread and side stile, wherein each rung member only has a front straight bar portion and an orthogonal side straight bar portion in that each straight bar terminates orthogonally at the at least one rail at one end of the rung, thereby allowing for a vertical grab rail portion at an adjacent opposite side of the at least one rail and the side straight bar portion terminates at the respective half tread at an opposite end of the rung and wherein the rung members are alternately arranged vertically such that vertically adjacent side bars and respective half treads are located at opposite side stiles. 
     The length of each grab rail portion may be twice that of the spacing between vertically adjacent half treads. 
     Vertically adjacent grab rail portions may be oppositely located. 
     Vertically adjacent grab rail portions may overlap by the same distance as spacing between vertically adjacent half treads 
     Each set of half treads may be located at an inner side of each respective stile. 
     Each side straight bar portion may not directly connect to an adjacent stile. 
     The straight bar portion may connect directly to a respective half tread. 
     Each straight bar portion may connect at an inner edge of a respective half tread. 
     Each straight bar portion may connect parallel to the inner edge. 
     Each straight bar portion may connect underneath the half tread. 
     Each half tread may comprise a major planar horizontal portion for stepping upon and an outer orthogonal raised flange. 
     The at least one rail may be extruded and defines an inner open channel there along. 
     The at least one front vertical rail may comprise two front vertical rails and wherein each front straight bar portion extends directly between the two front vertical rails. 
     Each rung may bend to the side straight bar portion outside the two front vertical rails. 
     Each side stile may comprise connectors for connection to an adjacent side stile in vertical alignment and wherein ends of each side stile bear directly against each other. 
     The connectors may comprise plates which may overlap on one side of connected stiles and have collocating apertures for a fastener. 
     The vertical ladder may comprise a section devoid of front straight bar portions. 
     Other aspects of the invention are also disclosed. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Notwithstanding any other forms which may fall within the scope of the present invention, preferred embodiments of the disclosure will now be described, by way of example only, with reference to the accompanying drawings in which: 
         FIG. 1  shows a top perspective view of a vertical ladder in accordance with a first embodiment; 
         FIG. 2  shows a top perspective view of a vertical ladder in accordance with a second embodiment; 
         FIG. 3-6  illustrate the utilisation of the ladder of the first embodiment; 
         FIG. 8  shows a rear perspective view of a vertical ladder in accordance with third embodiment; 
         FIG. 9  shows a rear elevation view of the ladder of the third embodiment; 
         FIG. 10  shows a top perspective view of the letter of the third embodiment. 
         FIG. 11  shows a vertical ladder in accordance with fourth embodiment; 
         FIG. 12  shows stile connectors in accordance with an embodiment; and 
         FIGS. 13 and 14  illustrate the utilisation of the ladder against a building. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
       FIG. 1  shows a vertical ladder  100  in accordance with a first embodiment. The ladder  100  comprises two vertical side stiles  101  and two front vertical rails  102 . 
     The two front vertical rails  102  are located further in from the sides of the ladder  100  as compared to the two side stiles  101  as can be more readily appreciated from  FIG. 5 . 
     The ladder  100  comprises two sets of half treads  103  supported in vertical alignment by respective side stiles  101 . 
     The ladder  100  further comprises a plurality of rung members  104  connected between the rails  102  and a respective half tread  103  or side stile  101 . 
     Each rung  104  only has a front straight bar portion  105  which transitions at an elbow portion  106  to a side straight bar portion  107 . 
     Each front straight bar portion  105  terminates orthogonally (i.e. at a T-junction) at one end of the rung  104  at a respective front rail  102 , thereby allowing a vertical grab rail portion  108  at an opposite adjacent side of the respective rail  102  for gripping and counterbalance. 
     Each associated side straight bar portion  107  terminates at an opposite end of the rung  104  at half tread is illustrated or alternatively directly to the respective side stile  101 . 
     Utilisation of the ladder  100  is illustrated in  FIGS. 3-7 .  FIG. 7  illustrates the half treads  103  being spaced apart such that a user is able to fit therebetween whilst holding onto the rungs  100  for and front. The rear of the ladder  100  may be open. 
     The user climbs the ladder  100  by stepping sideways onto each half tread  103 . Furthermore, as the half treads  103  are alternately vertically staggered, the user is able to shift the user&#39;s centre of gravity from side to side between the opposing sets of half treads  103  while ascending or descending the ladder  100 . In this way, the user may even climb the ladder without holding on. 
     The user may hold onto a rung  104  and various portion thereof, including the front straight bar portion  105 . In embodiments shown in  FIG. 5 , the user holds the straight bar portion to the right of the right-hand rail  102  with the right hand. Alternatively, the user may choose to hold the straight bar portion  105  between the front rails  102 . 
     As is further illustrated in  FIG. 5 , the user is shown as stepping up with the right foot whilst bearing the user&#39;s body weight with the left foot. As such, the user centre of gravity shifts to the right. As such, the user may counterbalance with the left-hand applied sideways to the vertical grab rail portion  108 . 
     The length of each grab rail portion is twice that of between vertically adjacent half treads  103  (or of the same length of vertically adjacent half treads  103  of each stile  101 ). 
     As such, and with reference to  FIG. 5 , the length of the left-hand grab rail portion  108  being held by the user has the same length as that of the spacing between vertically adjacent half treads of the right stile  101  such that, as the user steps up with the right hand foot, the user may grab the grab rail portion along the length of the grab rail portion which matches the travel distance of the right foot. 
     Furthermore, vertically adjacent grab rail portions  108  are oppositely located and overlap by the same distance as between vertically adjacent half treads  103  such that each vertically adjacent grab rail portion is located for gripping for each corresponding half tread. 
     Sections of vertical ladder  100  may be provided which may be vertically connected using connectors  109  shown in further detail in  FIG. 12 . The connectors  109  are shown in  FIG. 1  as connecting vertically adjacent side stiles  101  but, in other embodiments, the connectors  109  may be utilised also for connecting the front rails  102 . 
       FIG. 12  shows an embodiment of a connector  109  having overlapping plates  110  having collocating fastener apertures  111  for the receipt of a bolt  112  therethrough. 
     The connector  109  may comprise an inner plate  110 A and an outer plate  110 B which comprises a wider portion  113  extending to a narrower portion  114  which locate adjacent the inner plate  110 A when the respective stiles  101  are in alignment. In this configuration, the ends of the adjacent stiles  101  abut directly together, thereby enhancing the weight bearing capability of the ladder  100 . 
     Each front rail  102  is preferably of limited cross section so as to be easily gripped. As is also shown in  FIG. 1 , the front rails  102  may also square bar, but in other embodiments, the front rails  100  to may comprise round bar for more ergonomic gripping. 
     The rungs  104  shown in  FIG. 1  may comprise round bar. 
     Manufacture of the ladder  100  may comprise cutting each rung  104  to length and bending the elbow portion  106  thereof using a pipe bender. Each rung  105  may then be welded to inner faces of each rung  102  and side stile  101 . 
     In the embodiment shown in  FIG. 1 , each half tread  103  may locate at an inner face of each respective side stile  101 . In this way, the user can step onto each half tread between each side stile  101 . Furthermore, in embodiments shown in  FIG. 1 , each half tread  103  may be connected to each respective side stile  101  so as to extend both in front and behind the respective side stile  101 . In this way, travel of the foot beyond the half tread  103  may be arrested by the adjacent side stile  101  substantially midway the half tread  103 . 
     In embodiments, each half tread  103  may comprise a major horizontal portion  115  for stepping on which rises orthogonally at an outer flange  116 , thereby further guiding the placement of the foot. 
     Furthermore, and in the embodiment shown in  FIG. 1 , each side straight bar portion  107  may not directly connect with the respective side stile  101 . Rather, the side straight bar portion  107  may be directly connected to the half tread  103  wherein the half tread  103  is further directly connected to the respective side stile  101 . 
     In this way, the side straight bar portions  107  are located closer within reach. Furthermore, the side straight bar portions  107  may be partially stepped upon with the foot extending over the front of half tread  103  as shown in  FIG. 3 . In the embodiment shown in  FIG. 1 , the side straight bar portion  107  may be connected parallel with an inner edge of the half tread  103 . Furthermore, the side straight bar portion  107  may be connected to an undersurface of the half tread  103  as shown. Furthermore, the side straight bar portion  107  connected to the half tread  103  may only extend part way along the half tread  103 . In the embodiment shown, the portion of the straight side straight bar portion  107  connected to the half tread  103  extends substantially halfway therealong. 
       FIG. 2  shows a further embodiment of the vertical ladder  116  of a similar configuration except that it comprises a single front rail  101 . However, the vertical ladder  116  comprises a similar arrangement of rungs and rails allowing for use without hands, convenient holding and counterbalancing in the aforedescribed manner. 
       FIGS. 8-10  show third embodiment  117  of a vertical ladder comprising a single front rail  102 . In accordance with this embodiment, the front rail  102  may be extruded to comprise a major closed channel  118  as can be best seen from  FIG. 10 , through which the ends of each rung  104  may penetrate and a minor open channel  119  exposing a vertical track  120  therealong to which a vertical fall arrest device or the like may be engaged. 
     The fall arrest device may be used for additional safety where a user intends to climb the ladder without hands as alluded to above. Furthermore, in accordance with this embodiment, the elbow portion  106  of each rung  104  has a straight section as opposed to rounded. Furthermore, each side stile  101  may comprise a widened inner plate  121  reinforced with an outward channel section  122 . 
     Furthermore, each half tread  103  may comprise a horizontal section  123  which is folded over the adjacent side straight bar portion  107  to a strut portion  124  thereunderneath. 
       FIG. 11  shows a vertical ladder  125  in accordance with fourth embodiment. The vertical ladder  125  is of a simplified construction as compared to those aforedescribed in that each rung  126  comprises a front straight bar  127  portion transitioning at elbow portions  128  at either side thereof to respective straight side straight bar portions  129  which meet each half tread  103  in the aforedescribed manner. 
       FIGS. 13 and 14  illustrate application of the vertical ladder  100  for buildings. Specifically,  FIG. 13  illustrates the ladder  100  use for accessing a landing  130  and  FIG. 14  shows the ground level  131  thereunderneath. Ladder  100 A is outwardly orientated in that the user claims facing away from the building whereas ladder  100  B is inwardly orientated in that the climate climbs facing towards the building. 
     As shown in  FIG. 13 , the user may access entrances  133  part way up the building. The outwardly orientated vertical ladder  100 A may enclose the entrance  133  for safety. When arriving at the landing  131  from the outwardly orientated vertical ladder  100 A, the user may turn around to step on the landing. 
     However, the inward orientated vertical ladder  100 B may comprise a section  132  devoid of front straight bar portions  105 . As such, when arriving at the landing  130 , the user may step from the ladder  100  and be between the front rail is  102 . 
     With reference  14 , the outwardly orientated ladder  100  may similarly comprise a section  132  devoid of front straight bar portions  105  to allow the user to enter the ladder  100 A. 
     In alternative embodiments, the ladder may transition through  180 ° from the inward orientation  100 B shown in  FIG. 14  to the outward orientation  100 A shown in  FIG. 13 . 
     The foregoing description, for purposes of explanation, used specific nomenclature to provide a thorough understanding of the invention. However, it will be apparent to one skilled in the art that specific details are not required in order to practise the invention. Thus, the foregoing descriptions of specific embodiments of the invention are presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed as obviously many modifications and variations are possible in view of the above teachings. The embodiments were chosen and described in order to best explain the principles of the invention and its practical applications, thereby enabling others skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated. It is intended that the following claims and their equivalents define the scope of the invention.