Multi-position ladder and support therefor

Information

  • Patent Grant
  • 6315078
  • Patent Number
    6,315,078
  • Date Filed
    Wednesday, June 28, 2000
    24 years ago
  • Date Issued
    Tuesday, November 13, 2001
    22 years ago
  • Inventors
  • Original Assignees
    • (Burton, OH, US)
  • Examiners
    • Stodola; Daniel P.
    • Thompson; Hugh B.
    Agents
    • Eschweiler & Associates, LLC
Abstract
A multi-position ladder includes a ladder, a longitudinally extending support member for supporting the ladder, and a tightening mechanism associated with the ladder or the support member. The tightening mechanism is operable to secure the ladder to the support member, thereby prohibiting movement of the ladder along the support member.
Description




FIELD OF THE INVENTION




The present invention relates to a tightening knob which serves as a securing device for a multi-position ladder and the support therefor, and, more particularly, a device that secures the ladder in place while in use or storage.




BACKGROUND OF THE INVENTION




Prior art ladders used in industry and construction are often specifically designed to gain quick access to materials on the roof of a vehicle or on a shelf in a warehouse. In the case of a vehicle, for example, a construction van or truck, the ladder is typically vertically mounted relatively parallel to the side or rear of the vehicle in a single fixedly attached position. In this regard, a worker must maneuver the vehicle prior to loading or unloading materials to orientate the ladder to an accessible position relative to the desired material's site. This, oftentimes, is inconvenient, for example, in tight work zones or storage places.




In the case of a warehouse, typically the ladder must be removed from a storage site, carried to the desired material's location, raised to the desired height for loading or unloading of materials, lowered and then returned to the storage site. This can be burdensome and inconvenient, especially in crowded work zones or if frequent loading and unloading is required.




What is needed is a ladder that may be conveniently moved to an out-of-the-way yet accessible position, conveniently positioned for access to the roof of a vehicle or a shelf of a warehouse, and also readily and conveniently returned to its storage position.




SUMMARY OF THE INVENTION




The present invention provides a tightening knob with threaded posts therein to serve as a security device against lateral shifting of the multi-position ladder while in use and to serve as an additional security measure against involuntary or accidental separation of the ladder from its support member while in storage.




According to one aspect of the invention, the tightening knob includes a knob attached to a threaded post which extends in a generally perpendicular manner against the support member, a second, wider threaded post through which the first threaded post may be threaded, and a lock nut securing the wider threaded post, and having the entire device coupled with the ladder pivot arm. The knob may be twisted manually in either a clockwise or counter-clockwise rotation in order to engage the inner threaded post with the outer threaded post, thus securing the inner threaded post against the support member. This engagement between the inner threaded post and the support member in turn creates a frictional engagement between the threaded post and the support member preventing the ladder from shifting in a lateral direction.




Alternatively, the tightening knob can then be manually rotated in an opposite direction in order to lessen the frictional engagement between the inner threaded post and the support member, thus allowing for lateral movement of the multi-position ladder as needed.




Although the invention is shown and described with respect to one or more preferred embodiments, it is to be understood that equivalents and modifications will occur to others skilled in the art upon the reading and understanding of the specification. The present invention includes all such equivalents and modifications, and is limited only by the scope of the claims.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a perspective view of a multi-position ladder constructed in accordance with the present invention;





FIG. 2

is a front elevation view of the support member of the multi-position ladder of

FIG. 1

;





FIG. 3

is a perspective view of an end of the support member of the multi-position ladder of

FIG. 1

shown from the plane


3





3


in

FIG. 2

;





FIG. 4

is a front elevation view of the connecting member of the multi-position ladder of

FIG. 1

shown with the sliding bar and pivot arm rotated slightly out of position relative to the rotating arm for clarity purposes;





FIG. 5

is a front elevation view of the multi-position ladder of

FIG. 1

showing the multi-position ladder on the side of a vehicle in one of multiple generally vertical use positions and, in phantom, in another one of multiple generally vertical use positions;





FIG. 6

is a front elevation view of the multi-position ladder of

FIG. 1

showing the multi-position ladder on the side of a vehicle in one of multiple storage positions and, in phantom, in another one of multiple storage positions;





FIG. 7

is a side elevation view of the multi-position ladder of

FIG. 1

shown from the plane


7





7


in FIG.


1


and showing the ladder, in phantom, in a position pivoted away from the wall of the vehicle or the frame of a warehouse shelf;





FIG. 8

is an alternative embodiment of a connecting member constructed in accordance with the present invention and, more particularly, a connecting member adapter for connecting an existing ladder to the support member of the present invention;





FIG. 9

is a perspective view of an exemplary existing ladder for connection with the connecting member of

FIG. 8

;





FIG. 10

is a perspective view of a multi-position ladder constructed in accordance with another embodiment of the present invention;





FIG. 11A

is a side elevation view of the multi-position ladder of

FIG. 10

showing the ladder resting on a surface having the same elevation as a vehicle to which the ladder is connected;





FIG. 11B

is a side elevation view of the multi-position ladder of

FIG. 10

showing the ladder resting on a surface having a different elevation than a vehicle to which the ladder is connected;





FIG. 12A-12D

are sequential side elevation views of the ladder of

FIG. 10

showing the ladder being positioned to a different tilt angle;





FIG. 13

is a perspective view of a multi-position ladder constructed in accordance with another embodiment of the present invention;





FIG. 14

is a bottom plan view of a ladder constructed in accordance with another embodiment of the present invention and showing locking assembly for selectively locking the ladder in a storage position.





FIG. 15



a


is an exploded side perspective view of a tightening device showing a tightening knob coupled with an inner threaded post, a threaded lock nut, and an outer threaded post in a pre-engaged alignment and illustrating their interaction with the multi-position ladder;





FIG. 15



b


is a side perspective view of the tightening device of

FIG. 15



a


showing the inner threaded post fully engaged with the outer threaded post and the posterior end of the inner threaded post abutting the support member;





FIG. 16

is an exploded side perspective view of the tightening device of

FIG. 15



a


showing a tightening knob coupled with an inner threaded post, an outer threaded post, and a threaded lock nut, in a pre-engaged alignment;





FIG. 17



a


is a side perspective view of the tightening device of

FIG. 16

showing the inner threaded post in a partially engaged position with the outer threaded post, and showing the threaded lock nut engaged with the outer threaded post; and





FIG. 17



b


is a side perspective view of the tightening device of

FIG. 16

showing the inner threaded post fully engaged with the outer threaded post.











DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS




The present invention, as is detailed in the following diagrams, refers to a tightening mechanism which, when tightened, creates a frictional engagement between one aspect of the mechanism and the support member of the multi-position ladder. Such an engagement is advantageous to prevent lateral sliding of the multi-position ladder while in use or when in a stored position.




Referring now to the Figures, there is seen in

FIG. 1

a multi-position ladder constructed in accordance with the present invention generally indicated at reference numeral


10


. The multi-position ladder


10


includes a longitudinally extending support member


14


preferably fixedly mounted (not shown), for example, to the side or rear of a vehicle or to the frame of a warehouse shelf. A connecting member


18


is mounted to the support member


14


and is adapted to carry laterally therealong a ladder


22


from one end or side


26


of the support member


14


to the other end or side


30


of the support member


14


; the arrows A—A in

FIG. 1

being representative of the lateral motion of the ladder


22


.




The connecting member


18


includes an outwardly extending pivot arm


34


. The ladder


22


is pivotably mounted to the pivot arm


34


via a bushing


38


or other suitable pivotable connection for permitting the ladder


22


to be pivoted, or swung, from side-to-side. This pivoting motion may be, for example, as shown in

FIG. 1

, in the same plane as the plane of lateral shifting motion; the arc B—B in

FIG. 1

being representative of such pivoting motion of the ladder


22


. As will be described below, the plane of pivoting motion varies with respect to the tilt position of the ladder


22


. A rotating arm


42


is preferably rotatably mounted to the pivot arm


34


and preferably pivotably mounted to ladder uprights


43


of the ladder


22


for permitting the ladder


22


to tilt away from or towards a wall to which the support member


14


is attached. As shown in

FIG. 1

, the tilting is in a plane perpendicular to the aforedescribed lateral shifting motion and pivoting motion of the ladder


22


; the arc C—C in

FIG. 1

being representative of such tilting motion of the ladder


22


.




In view of the foregoing, it will be appreciated that the ladder


22


may be moved from side-to-side along the support member


14


to any of a wide range of generally vertical use positions, thus permitting a worker to move the ladder


22


to a position, for example, having the most direct or convenient access to materials on the roof of a vehicle or on the shelf of a warehouse. After use, the ladder


22


can then be pivoted, or swung, about the pivot arm


34


along the arc B—B and raised to a suitable storage position sufficiently high to clear the ground or warehouse floor, or to an otherwise “out-of-the-way” position. The ladder


22


may also be tilted outwardly away from the wall of the vehicle or shelf of a warehouse so that it is raised up from the ground (or floor) to facilitate easier lateral shifting motion or pivoting motion. These and other advantages, as well as the structure, function and features of the multi-position ladder


10


, are described in greater detail below.




The mounting arrangement between the connecting member


18


and support member


14


is described herein with respect to a sliding bar


44


in slidable engagement with a generally C-shaped guide channel


46


. The C-shaped guide channel


46


preferably has a lubricant, for example, silicone grease within its groove or a polytetrafluoroethylene coating on its interior walls, for facilitating sliding contact between the surface of the sliding bar


44


and the interior walls. The guide channel


46


includes a groove


50


adapted to slidably receive and provide stabile interface contact with the sliding bar


44


. The guide channel


46


and sliding bar


44


cooperatively engage to support the weight of the ladder


22


and/or a worker and load thereon. Of course, a round shaped guide channel may be used as an alternative, in which case the sliding bar


44


may include a bushing or other lubricating sleeve for promoting slidability between the round shaped guide channel and the sliding bar


44


.




It will be appreciated that the aforedescribed components may be reversed to accomplish substantially the same result; that is, the support member


14


may include a sliding bar


44


and the connecting member


18


may include a C-shaped guide channel


46


that rides laterally along the sliding bar


44


. In another alternative embodiment, the support member


14


may include a track or rail and the connecting member


18


may include guide pins or rollers that slidably engage the track or rail during lateral movement of the ladder


22


. In this regard, it will be appreciated that alternative parts and/or arrangements may be used to accomplish the same effect of guided lateral shifting movement of the connecting member


18


relative to the support member


14


and such alternatives are contemplated as falling within the scope of the present invention.




The C-shaped guide channel


46


includes suitable fasteners


54


(shown in

FIGS. 1 and 2

, for example) for securing the sliding bar


44


with respect to the groove


50


of the guide channel


46


when no lateral shifting movement of the ladder


22


along the guide channel


46


is desired. In the illustrated embodiment, the fasteners


54


comprise set screws


54


although there may be other suitable fasteners for preventing sliding movement of the sliding bar


44


relative to the groove


50


. For example, a pin could be inserted through transverse holes in the guide channel


46


for preventing movement of the sliding bar


44


with respect to the guide channel


46


.




The set screws


54


, or other suitable fasteners, may include eye hooks


58


or handles extending therefrom for facilitating a firm grip for tightening the set screws


54


. Preferably, the set screws


54


are tightened until they bear against and engage the sliding bar


44


which, in turn, forces a frictional engagement between the sliding bar


44


and guide channel


46


and, consequently, prevents lateral shifting movement of the ladder


22


relative to the vehicle wall or warehouse shelf. As illustrated in

FIGS. 1 and 2

, the spacing between two adjacent set screws


54


is preferably less than the length of the sliding bar


44


so that at least one set screw


54


is available for securing the sliding bar


44


during use. Of course, depending on the requirements of a particular application, the spacing may be narrower so that, for example, at least two fasteners


54


are available for securing the sliding bar


44


.




The guide channel


46


also defines an elongated slot


62


in substantial alignment with the groove


50


of the guide channel


46


as illustrated in FIG.


3


. The slot


62


is adapted to slidably receive therein the pivot arm


34


extending laterally outwardly from the sliding bar


44


. In this regard, the pivot arm


34


acts as a guide pin. As the sliding bar


44


is moved slidably through the guide channel


46


, the pivot arm


34


(acting as a guide pin) guides the sliding bar


44


along a relatively straight path as the pivot arm


34


travels within the slot


62


. As the pivot arm


34


slidably engages the edges of the slot


62


, the sliding bar


44


aligns itself within the groove


50


thereby facilitating relatively smoother for freer lateral shifting movement of the sliding bar


44


through the groove


50


. For even freer movement, a lubricant, for example, silicone grease or a polytetrafluoroethylene coating, may be applied to the surface of the pivot arm


34


and the coacting edges of the slot


62


.




In operation, lateral shifting movement of the ladder


22


translates into sliding movement of the sliding bar


44


within and along the C-shaped guide channel


46


. As shown in FIG.


5


and as can be appreciated in view of the foregoing, the ladder


22


may be laterally shifted to any desirable generally vertical use position along the guide channel


46


. In this sense, generally vertical is defined to mean a generally upright position. Therefore, the ladder


22


is in a generally vertical configuration while the ladder


22


is laterally shifted across the guide channel


46


although the ladder


22


may be, and of course usually will be, slightly tilted relative to, for example, the side or rear wall of a vehicle or the frame of a warehouse shelf, as shown in FIG.


7


and described below in greater detail.




Once the desired position is attained, the ladder


22


may be secured to the guide channel


46


by tightening the fasteners


54


. A worker may then climb the ladder


22


for loading or unloading of materials from, for example, the roof of a vehicle or a warehouse shelf. Should the worker desire closer access to materials further down the roof or shelf, the worker can loosen the fasteners


54


and simply laterally shift the ladder


22


to a more convenient position. Alternatively, the ladder


22


may be laterally shifted to one of the ends


26


,


30


of the guide channel


46


and removed therefrom or pivoted to a storage position, as described below in greater detail. The fasteners


54


may then be tightened to secure the ladder


22


in its storage position.




As was alluded to above, the pivot arm


34


also permits the ladder


22


to pivot, that is, swing from side-to-side as is generally represented by the arc-shaped line B—B shown in FIG.


1


. As shown in greater detail in

FIG. 4

, the connecting member


18


further includes the rotating arm


42


which is rotatably mounted at its center onto the pivot arm


34


. A bushing


38


or other suitable coupling or bearing member, for example, a roller bearing, is interposed between the pivot arm


34


and rotating arm


42


to ensure relatively stabile rotatable movement of the rotating arm


42


about the pivot arm


34


. In the preferred embodiment, the pivot arm


34


includes a boss


64


(

FIG. 7

) and a polytetrafluoroethylene washer (now shown) against which the rotating arm


42


bears. A polytetrafluoroethylene washer (not shown) and a threaded lug nut


65


retain the rotating arm


42


at the end of the pivot arm


34


.




Of course, other suitable pivoting arrangements may be employed to obtain substantially the same result. Thus, for example, in an alternative embodiment, the rotating arm


42


may be fixedly attached to the pivot arm


34


and the pivot arm


34


, in turn, pivotably connected to the sliding bar


44


. In this regard, the slot


62


may be sized to accommodate such pivotable movement by, for example, providing enlarged, preferably circular, openings spaced along the slot


62


and adapted to receive the width or diameter of the pivot arm


34


as it is pivoted and thereby travels in an arcuate or circumferential path. In another alternative embodiment, the pivot arm


34


itself may be adapted to provide such pivotable movement. The pivot arm


34


may be fixedly attached to both the sliding bar


44


and the rotating arm


42


, in which case the sliding bar


44


and rotating arm


42


would take the form of T-shaped brackets and may include an axial coupling proving pivotable movement, or essentially swivelled movement, between the sliding bar


44


and rotating arm


42


. In this regard, it will be appreciated that alternative parts and/or arrangements may be used to accomplish the same effect of pivoting movement of the rotating arm


42


along the arc B—B (

FIG. 1

) and such alternatives are contemplated as falling within the scope of the present invention.




Referring to

FIG. 4

, the ends


66


of the rotating arm


42


are rounded and are pivotably received in correspondingly sized holes


70


in the upper portion of the ladder uprights


43


. A bushing


78


or other suitable bearing member may be disposed within the holes


70


to ensure relatively stabile pivotable movement of the rotating arm's ends


66


within the respective holes


70


. In the preferred and illustrated embodiment, the rotating arm


42


takes on the same shape as, and is substantially parallel to, the rungs


80


of the ladder


22


and may even be used as a top rung when the spacing requirements of a particular application permit. Suitable fasteners, for example, such as those described hereinabove, may be used at the pivot and rotate locations to maintain a relatively fixed connection at, and to prevent pivoting or rotating movement of, the rotating arm


42


relative to the pivot arm


34


and the ladder uprights


43


.




In operation, pivoting of the ladder


22


from side-to-side along the arc B—B (

FIG. 1

) translates into rotating of the rotating arm


42


about the pivot arm


34


. As shown in FIG.


6


and as can be appreciated in view of the foregoing, the ladder


22


may be pivotably moved to any desirable storage position and, most preferably, a generally non-vertical storage position. In this sense, generally non-vertical is defined to mean any position other than a generally upright position. The ladder


22


may be pivotably moved from side-to-side although the ladder


22


may be, and of course usually will be, slightly tilted relative to, for example, the side or rear wall of a vehicle of the frame of a warehouse shelf, as shown in FIG.


7


and described below in greater detail. Once a desired storage position is attained, the ladder


22


may be secured to the guide channel


46


at the pivot end of the ladder


22


by tightening one or more of the fasteners


54


and/or to the vehicle side wall or the frame of a warehouse shelf at its free end by other suitable fastening means (not shown).




Referring now to

FIG. 7

, it is seen that the connecting member


18


also facilitates tilting of the ladder


22


outwardly and/or inwardly with respect to the wall or frame (not shown) to which the guide channel


46


is mounted. The rotating arm


42


permits the ladder uprights


43


to rotate about the rotating arm


42


in a plane (for example, line C—C in

FIG. 1

) perpendicular to the plane of lateral shifting movement of the ladder


22


(for example, line A—A in FIG.


1


). Advantageously, by tilting the ladder


22


in such a manner, the lower ends of the ladder uprights


43


are raised above the ground (or floor) thereby providing a clearance, or gap, that facilitates relatively easier lateral shifting movement of the ladder


22


across the guide channel


46


or pivotable movement of the ladder


22


about the pivot arm


34


. Also, the inclination angle of the ladder


22


may be adjusted by placing the block or other suitable support beneath the ladder uprights


43


after raising the ladder


22


by tilting.





FIG. 8

shows a connecting member adapter


82


that may be used to adapt the connecting member


18


to an existing ladder


84


(FIG.


9


). The adapter


82


includes a pair of U-shaped members


86


. One leg


90


of each U-shaped member


86


pivotably fits into a correspondingly sized receiving hole


94


in the top of respective ladder uprights


98


. Alternatively, the legs


90


may be pivotably mounted into ends


100


of a rung


101


. To this end, the rung


101


is fixed relative to the ladder uprights


98


and includes an inside diameter sized to receive the legs


90


. The other let


102


forms a collar, or sleeve, the inside diameter of which corresponds to the outside diameter of an end


66


of the rotating arm


42


. The ends


66


of the rotating arms


42


are inserted into the respective collar legs


102


and then secured thereto by fasteners


106


, for example, a set screw or the like, for fixedly connecting the U-shaped member


86


to the rotating arm


42


. Of course, the U-shaped member


86


may be reversed to accomplish substantially the same result. Thus, the legs


102


may be pivotably connected to the ends


66


of the rotating arm


42


while the other legs


90


are secured into the correspondingly sized receiving holes


94


in the ladder uprights


98


.




Referring now to

FIG. 10

, there is shown an adjustment mechanism in accordance with the present invention generally indicated at reference numeral


110


. In the several Figures, like reference numerals correspond to like components. The adjustment mechanism


110


permits adjustments of the ladder


22


by sliding the ladder


22


relative to the connecting member


18


along the extent of the ladder


22


. When the ladder


22


is in a generally vertical use position, the adjustment mechanism


110


allows the ladder


22


to be selectively adjusted in a generally vertical direction thereby to provide greater clearance below the bottom of the ladder


22


for tilting the ladder


22


outwardly away from the vehicle or warehouse wall or otherwise adjusting the ladder


22


for varying ground surfaces.




The adjustment mechanism


110


includes a pair of inserts


112


, preferably made of nylon, that are slidably received within respective guide tracks or channels


114


disposed in the uprights


43


of the ladder


22


. The guide tracks


114


cooperatively engage the inserts


112


to provide substantially uniform movement of the ladder


22


relative to the connecting member


18


. To facilitate sliding contact between the inserts


112


and the guide tracks


114


, the guide tracks


114


may include a polytetrafluoroethylene coating or other lubricant on their interior walls.




The inserts


112


are rotatably connected to respective ends of the rotating arm


42


of the connecting member


18


to enable the ladder


22


to be tilted towards or away from the vehicle wall or warehouse shelf in a manner similar to that described above. Tightening knobs


120


extend through the respective inserts


112


and are threaded to the ends of the rotating arm


42


or, alternatively, are attached with a nut and bolt to the rotating arm


42


. When tightened, the tightening knobs


120


maintain the rotating arm


42


fixed with respect to the ladder uprights


43


. When loosened, the tightening knobs


120


free the connection between the rotating arm


42


and the ladder uprights


43


.




The inserts


112


may additionally and/or alternatively be in the form of rotatable disks or wheels (not shown) to provide rolling contact in the guide tracks or channels


114


. Also, while the nylon inserts


112


are shown in

FIG. 10

to be disposed on the outside of the ladder uprights


43


, they could alternatively be disposed on the inside of the ladder uprights


43


. Of course, the tightening knobs


120


would likewise be located on the inside of the ladder uprights


43


. Further still, the adjustment mechanism


100


may not include inserts


112


, in which case the tightening knobs


120


provide sufficient locking force to secure the rotating arm


42


with respect to the ladder


22


.




The uprights


43


of the ladder


22


include elongated slots


124


that extend along a portion of the length of the ladder


22


. In the illustrated exemplary embodiment, the slots


124


extend from near the top portion of the ladder


22


to near the second rung of the ladder


22


. The slots


124


slidably receive therethrough the respective ends of the rotating arm


42


of the connecting member


18


. The sliding engagement between the ladder uprights


43


and the ends of the rotating arm


42


via the respective slots


124


provides guided movement of the adder


22


along its length dimension or, as shown in the illustrated embodiment, in an upward or downward generally vertical direction. Like the guide tracks


114


, the slots


124


may include a lubricant to facilitate sliding contact between the ladder uprights


43


and the ends of the rotating arm


42


.




As alluded to above, the adjustment mechanism


110


allows the ladder


22


to be adjusted to compensate for differences in the spacing between the longitudinally extending support member


14


and the ground, floor or other surface on which the ladder


22


may rest. Thus, in one instance the bottom of the ladder


22


may be at the same elevation as, for example, the vehicle shown in FIG.


11


A. In another instance, as shown in

FIG. 11B

, the bottom of the ladder


22


may require resting on a surface such as a curb


126


that is slightly higher in elevation than the surface on which the vehicle rests, in which case the ladder


22


may be adjusted upwardly to compensate for the difference in elevation.




The adjustment mechanism


110


also enables the slope or tilt of the ladder


22


to be adjusted to different angles relative to the ground. Referring to

FIGS. 12A-12D

, for example, it may be desirable to have the ladder


22


sloped at a smaller angle than that shown in

FIG. 12A

to make the climbing thereof easier. To change the slope of the ladder


22


, a user may simply loosen the tightening knobs


120


, slide the ladder


22


vertically upwardly (FIG.


12


B), tilt the ladder


22


outwardly way frm the side of the vehicle wall (FIG.


12


C), slide the ladder


22


vertically downwardly (FIG.


12


D), and then tighten the tightening knobs


120


to thereby secure the ladder


22


in its new position.




As can be appreciated by the foregoing, the path of travel of the ladder


22


is a function of the dimensions of the slots


124


. To this end, as shown in

FIG. 13

, the slots


124


may additionally include segments


128


for enabling the ladder


22


to be vertically adjusted in increments to decrease or increase the spacing between the bottom of the ladder


22


and the ground. The segmented slots


128


may also facilitate tilting the ladder


22


to different angles relative to the ground, in which case each segment would represent a different tilt angle.




Referring now to

FIG. 14

, there is shown a locking assembly in accordance with the present invention generally indicated at reference numeral


130


. The locking assembly


130


provides selective securing of the ladder


22


in a storage position by providing selective engagement of the bottom of the ladder


22


with the longitudinally extending support member


14


(see FIG.


1


).




The locking assembly


130


comprises a spacer bar


132


transversely attached to the ladder uprights


43


of the ladder


22


and an insert


136


, preferably made of nylon, in sliding engagement with the guide channel


46


of the longitudinally extending support member


14


. The spacer bar


132


and insert


136


are adapted to slidably connect a portion of the ladder


22


(preferably the bottom portion) to the guide channel


46


so that the spacing of the ladder


22


from the vehicle wall or warehouse shelf is substantially uniform. As shown in

FIG. 14

, the insert


136


is generally T-shaped to conform with the groove


50


of the C-shaped guide channel


46


. This secures the ladder


22


from outward movement (to the right in

FIG. 14

) from the support member


14


when the ladder


22


is in a storage position.




The locking assembly


130


includes upper and lower mounts


142


,


144


that are connected to the spacer bar


132


and are vertically aligned with respect to the insert


136


. The mounts


142


,


144


have holes


143


,


145


extending therethrough for slidably receiving therein a locking pin


148


. The locking pin


148


is biased upwardly by a spring


152


disposed between the lower mount


144


and a washer


154


that is connected to the pin


148


and abuts the upper mount


142


when the locking assembly


130


is in its engaged position.




To lock the ladder


22


in a storage position, the pin


148


is retracted as by pulling a handle


158


connected to the pin


148


to overcome the biasing force of the spring


152


and then the insert


136


is inserted into the guide channel


46


of the longitudinally extending support member


14


. After the insert


136


is inserted, the pin


148


may be released, in which case the pin


148


will slidably bear against the guide channel


46


. The ladder


22


is moved laterally along the guide channel


46


until the end of the pin


148


aligns with a locator hole


159


in the guide channel


46


. In the aligned position, the pin


148


automatically engages the hole


159


and preferably extends far enough into the hole


159


to engage the insert


136


inside the channel


46


. This provides a firm connection between the insert


136


and the support member


14


. Of course, the insert


136


may include a hole (not shown) aligned with the holes


143


,


145


of the mounts


142


,


144


for receipt therein of the end of the pin


148


to provide even greater stiffness i the connection. It will be appreciated that when the locking assembly


130


is in its engaged position the pin


148


locks the ladder


22


to a storage position by preventing lateral movement of the ladder


22


relative to the support member


14


.




To disengage the pin


148


from the hole


159


a user temporarily pulls the locking pin


148


to overcome the bias in the spring


152


and then retracts the ladder


22


a sufficient amount so that the pin


148


is no longer in alignment with the hole


154


. The user can then laterally slide the ladder


22


out of the guide channel


46


.




It is noted that additional holes may be provided in the guide channel


46


to permit the ladder


22


to be stored in one of numerous storage positions along the elongated support member


14


.




In an alternative embodiment (not shown), the guide channel


46


may include a ratcheting device and the ladder


22


may include a coacting lever that is automatically engaged by the ratcheting device (e.g., by spring biasing means) as the ladder


22


is slidably inserted into the elongated support member


14


to thereby secure the ladder relative to the guide channel


46


. To withdraw the ladder


22


from its storage position, the lever may then be depressed to thereby disengage the ratcheting device and allow the ladder


22


to be withdrawn from the guide channel


46


.




Referring again to

FIGS. 1

,


10


and


13


, a tightening knob


160


is preferably attached at the end of the pivot arm


34


for selectively securing the rotating arm


42


to the pivot arm


34


. By tightening the tightening knob


160


, the pivot arm


34


is secured to the rotating arm


42


which, in turn, allows one to maintain the sliding bar


44


parallel with respect to the rotating arm


42


. Thus, when the ladder


22


, and more particularly the insert


136


, is withdrawn from the guide track


46


, the sliding bar


44


will not inadvertently swivel at the bushing


38


. This simplifies insertion of the sliding bar


44


into the guide channel


46


of the support member


14


. Moreover, by tightening the tightening knobs


120


associated with the adjusting mechanism


110


, the connecting member


18


remains steady with respect to the ladder


22


. Thus, the entire ladder


22


, along with the connecting member


18


, may be laterally removed frm the guide channel


46


as an integral component without regard to inadvertent rotating or pivoting of interacting components. This is particular useful in situations where the user desires to move the ladder


22


from one guide track to another, for example, from a guide track on one side of a vehicle to a guide track on the other side of the vehicle.




Moreover, the adjustment mechanism


110


and tightening knob


160


enable the ladder to be stored in a vertical position as by sliding the ladder


22


vertically upwardly until the bottom of the ladder


22


is a sufficient height from the ground (or, for example, until the rotating arm


42


reaches the bottom of the slots


124


) and then tightening the tightening knobs


120


and


160


. It will be appreciated that since the ladder


22


may also be pivoted about the pivot arm


34


and then thereafter locked by the tightening knob


160


, that the ladder


22


may be stored in any of multiple storage positions between a vertical position and, as described above, a horizontal position.




In view of the foregoing, it will be appreciated that the support member


14


and connecting member


18


of the present invention facilitate three types of movement of the ladder


22


, namely lateral shifting movement along the C-shaped guide channel


46


, pivotable movement about the pivot arm


34


from side-to-side, and tilting movement about the rotating arm


42


away from and towards the wall or frame to which the guide channel


46


is connected. The movements may be made either simultaneously or independently depending on, of course, the limitations or needs of a particular loading/unloading site. Also, in the case of a vehicle, additional support members


14


may be mounted to the rear and/or other side of the vehicle to facilitate substantially 270 degree access to the roof of the vehicle. Similarly, additional support members


14


may be mounted to multiple frame members


14


of a warehouse shelf or shelves. In this regard, the support members


14


may be mounted at different levels of shelves so that, for example, adjacent levels may have their ladders


22


selectively aligned for climbing the ladders


22


in sequence and gaining access to the two adjacent levels. After loading and/or unloading is completed, the ladders


22


can then be selectively pivoted to an out-of-the-way storage position. In either case, the multi-position ladder


10


may be conveniently moved to an out-of-the-way yet accessible position, conveniently positioned for access to a loading/unloading site, and readily and conveniently returned to its storage position.




Referring to

FIG. 15



a


, a tightening device is shown generally and indicated at reference numeral


162


. The tightening device


162


includes a tightening knob


164


, an inner threaded post


166


, a threaded lock nut


172


, and an outer threaded post


168


. The inner threaded post


166


may be engaged with the outer threaded post


168


, proceed through the pivot arm


34


and sliding bar


44


, project out through a threaded hole


170


of the sliding bar


44


and abut the support member


14


.




The outer threaded post


168


may be threaded into the pivot arm


34


, through a washer


174


, and thread into the threaded hole


170


of the sliding bar


44


. According to one aspect of the present invention, the hollow portions of the pivot arm


34


and the sliding bar


44


are threaded and are of an adequate circumference so as to create an engagement between them and the outer threaded post


168


. A washer


174


may be employed so as to maintain a barrier between the pivot arm


34


and the sliding arm


44


.




It is appreciated that the outer threaded post


168


will serve as a guide for the inner threaded post


166


, thus allowing the inner threaded post


166


to be threaded therethrough so as to abut the support member


14


, allowing for the creation of a frictional engagement between the inner threaded post


166


and the support member


14


, and preventing the multi-position ladder to shift in a lateral direction along the support member


14


.




Referring to

FIG. 15



b


, the inner threaded post


166


is fully engaged with the outer threaded post (not shown) in a manner which causes the tightening knob


164


to abut the threaded lock nut (not shown) which in turn is abutting the pivot arm


34


. The posterior end or tip of the inner threaded post


166




b


abuts the support member


14


so as to create a frictional engagement between the tip of the inner threaded post


166




b


and the support member


14


, thus preventing lateral movement of the multi-position ladder


10


, as will be discussed in greater detail below.




Referring to

FIG. 16

, the tightening device


162


is shown in a pre-engaged alignment. According to one aspect of the present invention, the tightening device


162


includes a tightening knob


164


attached or otherwise coupled with or secured to an inner threaded post


166


which extends generally perpendicularly from the tightening knob


164


. The inner threaded post


166


may be completely threaded externally from a top end


166




a


to a bottom end or tip


166




b


thereof to allow for maximum engagement with an outer threaded post


168


and has a length “L


1


” great enough to allow for an adequate frictional engagement between the inner threaded post


166


and the support member


14


, as will be discussed in greater detail infra.




Alternatively, other suitable threaded arrangements may be employed to obtain the same functionality. Thus, for example, an inner threaded post


166


exhibiting partial threading along its length may be employed to achieve the same type of engagement with the outer threaded post


168


, and the same type of frictional engagement with the support member


14


. Further, other suitable member engagement arrangements may be employed to obtain the same functionality. For example, a racheting mechanism which utilizes a lock and release device between the inner post


166


and the support member


14


may be employed to achieve the same type of frictional engagement between the inner post


166


and the support member


14


. It is appreciated that such alternatives are contemplated as falling within the scope of the present invention.




As discussed above, the tightening device


162


further includes the outer threaded post


168


. The outer threaded post


168


is generally hollow or tubular with a threaded inner circumference (not shown) that adequately allows for a threaded engagement between the inner threaded post


166


and the outer threaded post


168


. The outer threaded post


168


may be fully threaded internally from a top end


168




a


to a bottom end


168




b


thereof to allow for maximum engagement between the outer threaded post


168


and the inner threaded post


166


. The outer threaded post


168


may also be fully threaded externally from its top end


168




a


to its bottom end


168




b


to allow for maximum engagement between the outer threaded post


168


and a pivot arm


34


(

FIG. 15



a


), a washer


174


(

FIG. 15



a


), and a threaded hole


170


(

FIG. 15



a


) of the sliding bar


44


.




Alternatively, other suitable threaded arrangements may be employed to obtain the same result. Thus, for example, an outer threaded post


168


of only partial threading along its interior or exterior lengths may be employed to ultimately achieve the same type of engagement between the outer threaded post


168


and the inner threaded post


166


as well as the outer threaded post


168


and the pivot arm


34


(

FIG. 15



a


), as discussed supra. It is appreciated that such alternatives are contemplated as falling within the scope of the present invention.




The tightening device


162


further includes a threaded lock nut


172


which allows for an engagement between the threaded lock nut


172


and the outer threaded post


168


. The threaded lock nut


172


is generally hollow with a threaded inner circumference of a measurement that adequately allows for an engagement between the threaded lock nut


172


and the outer threaded post


168


. Such an engagement between the threaded lock nut


172


and the threaded outer post


168


serves as a mechanism to ensure that the engagement between the outer threaded post


168


and the pivot arm


34


(

FIG. 15



a


) remains static.




Referring now to

FIG. 17



a


, there is shown the inner threaded post


166


in a position of partial engagement with the outer threaded post


168


. To achieve such engagement, the inner threaded post


166


is inserted or rotated into the hollow portion of the outer threaded post


168


, via the hollow portion of the threaded lock nut


172


.




The threaded lock nut


172


may be fully engaged with the outer threaded post


168


via manual twisting in either a clockwise or counter-clockwise rotation. That is to say, twisted in a rotation which promotes engagement between the threaded lock nut


172


and the outer threaded post


168


. Alternatively, the threaded lock nut


172


may be twisted in an opposite rotation to promote disengagement between the threaded lock nut


172


and the threaded outer post


168


.




The inner threaded post


166


may be fully engaged with the outer threaded post


168


via manual twisting of the tightening knob


164


in a rotation which promotes engagement between the inner threaded post


166


and the outer threaded post


168


. Alternatively, the tightening knob


164


may be twisted in an opposite rotation so as to promote disengagement between the inner threaded post


166


and the outer threaded post


168


. Such disengagement will eliminate the frictional engagement between the inner threaded post


166


and the support member


14


, thus allowing for lateral movement of the multi-position ladder


10


along the support member


14


.




Referring to

FIG. 17



b


, the inner threaded post


166


in a position of full engagement with the outer threaded post


168


is shown. As described supra, the inner threaded post


166


may be of a length great enough to exceed a length of the outer threaded post L


2


and protrude out of the threaded hole


170


of the sliding bar


44


so that the tip of the inner threaded post


166




b


may abut the support member


14


sufficiently, thus creating a frictional engagement between the inner threaded post


166


and the support member


14


.




It is noted that the various components, assemblies, devices and compositions of the present invention may be made with any type and/or number of suitable materials. The materials referred to in the description of the invention, as well as the claims appended hereto, are preferred materials. It will be appreciated that the present invention is not limited to any specific material usage.




Although the invention has been shown and described with respect to a certain preferred embodiment or embodiments, equivalent alterations and modifications will occur to others skilled in the art upon reading and understanding this specification and the annexed drawings. In particular regard to the various functions performed by the above described integers (components, assemblies, devices, compositions, etc.), the terms (including a reference to a “means”) used to describe such integers are intended to correspond, unless otherwise indicated, to any integer which performs the specified function of the described integer (i.e., that is functionally equivalent), even though not structurally equivalent to the disclosed structure which performs the function in the herein illustrated exemplary embodiment or embodiments of the invention. In addition, while a particular feature of the invention may have been described above with respect to only one of several illustrated embodiments, such feature may be combined with one or more other features of the other embodiments, as may be desired and advantageous for any given or particular application.



Claims
  • 1. A multi-position ladder, comprising:a ladder including a pair of spaced apart ladder uprights; a longitudinally extending support member for supporting said ladder; a connecting member connecting said support member and said ladder, said connecting member further comprising: a sliding bar member cooperatively engaging the longitudinally extending support member, wherein the sliding bar member permits lateral shifting movement and lateral positioning of the ladder to one of multiple generally vertical use positions along the longitudinally extending support member; a pivot arm coupled to the sliding bar member; and a rotating arm rotatably coupled to the pivot arm and pivotably coupled to the pair of spaced apart ladder uprights, wherein the rotating arm provides rotational movement of the ladder in a first plane which is generally perpendicular to a second plane defined by a lateral shifting movement of the ladder in the generally vertical use position along the support member, wherein the rotational movement alters an inclination angle of the ladder, and wherein the pivot arm provides pivotal movement of the ladder about a pivot point where the ladder couples to the support member via the connecting member, and wherein the pivotal movement occurs about the pivot point in an arc from side to side between a generally vertical use position and a horizontal storage position; a tightening mechanism coupled to the support member or the connecting member for securing the sliding bar of the connecting member to the support member and prohibiting movement of the sliding bar along the support member when the ladder is in use.
  • 2. A multi-position ladder, comprising:a ladder including a pair of spaced apart ladder uprights; a longitudinally extending support member for supporting said ladder; a connecting member connecting said support member and said ladder, said connecting member further comprising: a sliding bar member cooperatively engaging the longitudinally extending support member, wherein the sliding bar member permits lateral shifting movement and lateral positioning of the ladder to one of multiple generally vertical use positions along the longitudinally extending support member; a pivot arm coupled to the sliding bar member; and a rotating arm rotatably coupled to the pivot arm and pivotably coupled to the pair of spaced apart ladder uprights, wherein the rotating arm provides rotational movement of the ladder in a first plane which is generally perpendicular to a second plane defined by a lateral shifting movement of the ladder in the generally vertical use position along the support member, wherein the rotational movement alters an inclination angle of the ladder, and wherein the pivot arm provides pivotal movement of the ladder about a pivot point where the ladder couples to the support member via the connecting member, and wherein the pivotal movement occurs about the pivot point in an arc from side to side between a generally vertical use position and a horizontal storage position; a fastener coupled to the connecting member, wherein the fastener comprises an engagement member moveable between a non-engaged position in which the fastener does not engage the support member and the sliding bar is moveable along the longitudinally extending support member, and an engaged position in which the fastener engages the support member and prohibits movement of the sliding bar along the longitudinally extending support member.
  • 3. The multi-position ladder of claim 2, wherein the fastener further comprises an outer post having an inner threaded bore, and a threaded inner post, wherein the inner post and the outer post are adapted for threaded engagement therebetween, and wherein when the inner post is fully engaged with respect to the outer post, the inner post abuts a portion of the support member, thereby generating an interference fit therebetween.
  • 4. A multi-position ladder, comprising:a ladder; a support member for supporting said ladder, the support member being operable to mount to a wall, vehicle or other surface; a connecting member connecting said support member and said ladder; said connected member supported said ladder for sliding movement of said ladder relative to the connecting member along at least a portion of the length of the ladder, wherein said ladder includes uprights having elongated grooves disposed along at least a portion of the length of the ladder for slidably receiving therein said connecting member for guiding the ladder during sliding movement thereof, and wherein the connecting member includes an adjustment mechanism including respective inserts that are slidably received within the elongated grooves, and wherein the inserts cooperatively engage the elongated grooves of the ladder uprights to provide substantially uniform movement of the ladder relative to the connecting member; and a tightening mechanism for fixedly securing the ladder to the support member to thereby prevent longitudinal movement of the ladder along the support member.
  • 5. A multi-position ladder, comprising:a ladder; a support member for supporting said ladder, the support member being operable to mount to a wall, vehicle or other surface; a connecting member connecting said support member and said ladder; said connected member supported said ladder for sliding movement of said ladder relative to the connecting member along at least a portion of the length of the ladder, wherein said ladder includes an upright having one or more elongated slots disposed therein along at least a portion of the length of the ladder and said connecting member includes a rotating arm extending transverse to the length of the ladder, the ends of the rotating arm being in sliding engagement with said one or more slots during sliding movement of the ladder, and wherein said rotating arm is pivotably mounted at its ends within the slots for permitting tilting movement of said ladder; a tightening mechanism for fixedly securing the ladder to the support member to thereby prevent longitudinal movement of the ladder along the support member.
  • 6. A multi-position ladder, comprising:a ladder; a support member for supporting said ladder, the support member being operable to mount to a wall, vehicle or other surface; a connecting member connecting said support member and said ladder; said connecting member supporting said ladder for pivotal movement about a point where the ladder couples to the support member via the connecting member in an arc from side-to-side between a generally vertical use position and a storage position and for sliding movement of said ladder relative to the connecting member along at least a portion of the length of the ladder; and a locking assembly for selectively securing a free end of the ladder to the support member when the ladder is pivoted to a storage position, wherein the support member includes a locator hole and the locking assembly includes a locking pin that is biased to slidably engage the support member though the locator hole to prevent lateral movement of the ladder along the support member; and a tightening mechanism for fixedly securing the ladder to the support member to thereby prevent longitudinal movement of the ladder along the support member.
  • 7. A multi-position ladder, comprising:a ladder; a support member for supporting said ladder, the support member being operable to mount to a wall, vehicle or other surface; a connecting member connecting said support member and said ladder; said connecting member supporting said ladder for pivotal movement about a point where the ladder couples to the support member via the connecting member in an arc from side-to-side between a generally vertical use position and a storage position and for sliding movement of said ladder relative to the connecting member along at least a portion of the length of the ladder; and a locking assembly for selectively securing a free end of the ladder to the support member when the ladder is pivoted to a storage position, wherein the locking assembly further includes a locking mechanism connected to the ladder, the locking mechanism being selectively moveable between an engaged position to prevent lateral movement of the ladder along the support member and a disengaged position to permit said lateral movement, and wherein the locking mechanism includes at least one mount spaced apart from and aligned with the engaging member, the mount including a hole therethrough for receipt therein of a locking pin so that when the locking pin engages the support member through a locator hole associated with the support member, the locking pin engages the support member; and a tightening mechanism for fixedly securing the ladder to the support member to thereby prevent longitudinal movement of the ladder along the support member.
  • 8. A multi-position ladder, comprising:a ladder including a pair of uprights having respective guide tracks and elongated slots disposed therein along the length of the ladder; a longitudinally extending support member for supporting the ladder, the support member being operable to mount to a wall, vehicle or other surface; and a connecting member connecting the support member and the ladder; said connecting member including respective inserts that are slidably received within the guide tracks, the inserts cooperatively engaging the elongated slots of the ladder uprights to provide substantially uniform movement of the ladder relative to the connecting member, and a rotating arm extending transverse to the length of the ladder, the ends of the rotating arm being slidably received in the elongated slots for permitting tilting movement of the ladder, and sliding movement of the ladder along the ends of the rotating arm in a generally vertical direction; and a tightening mechanism for fixedly securing the ladder to the support member to thereby prevent longitudinal movement of the ladder along the support member.
  • 9. A multi-position ladder, comprising:a ladder; a longitudinally extending support member for supporting the ladder; and a tightening mechanism for securing the ladder to the support member, thereby prohibiting movement of the ladder along the support member.
  • 10. A multi-position ladder, comprising:a ladder; a longitudinally extending support member for supporting the ladder in a plurality of generally vertical use positions; a connecting member connecting the support member and the ladder; and a tightening mechanism coupled to the connecting member and adapted to engage the support member and substantially prevent movement of the ladder along the support member.
  • 11. The multi-position ladder of claim 10, wherein said tightening mechanism comprises an inner threaded post which threadingly engages a threaded hole associated with the connecting member so as to facilitate an engagement between the inner threaded post and the support member.
  • 12. The multi-position ladder of claim 11, wherein said tightening mechanism further comprises an outer post coupled to the connecting member through which said inner threaded post is threadingly engaged so as to induce an engagement between the inner threaded post and the support member.
  • 13. The multi-position ladder of claim 12, wherein the outer post is threaded on an outside portion and an inside portion thereof, and wherein the outer portion is threadingly engaged with a threaded hole associated with the connecting member.
  • 14. The multi-position ladder of claim 11, wherein said inner threaded post further comprises a means for manipulating said inner threaded post and facilitating said engagement between said inner threaded post and said support member, said manipulating means located on a distal end of said inner threaded post.
  • 15. The multi-position ladder of claim 14, wherein said manipulating means comprises a handle or a knob.
RELATED APPLICATIONS

This application claims priority to U.S. Provisional Application Ser. No. 60/209,820 filed Jun. 6, 2000, and also is a Continuation-in-Part of U.S. patent application Ser. No. 09/322,592 filed May 28, 1999,now U.S. Pat. No 6,105,720, which is a Continuation-in Part of U.S. application Ser. No. 09/186,863 filed Nov. 5, 1998, now U.S. Pat. No. 6,073,725 issued June 13, 2000.

US Referenced Citations (2)
Number Name Date Kind
6073725 Kumher et al. Jun 2000
6105720 Kumher et al. Aug 2000
Provisional Applications (1)
Number Date Country
60/209820 Jun 2000 US
Continuation in Parts (2)
Number Date Country
Parent 09/322592 May 1999 US
Child 09/605153 US
Parent 09/186863 Nov 1998 US
Child 09/322592 US