Apparatus providing single support to an extension ladder enabling ladder use on level and non-level surfaces
10100577 ยท 2018-10-16
Inventors
Cpc classification
E06C7/188
FIXED CONSTRUCTIONS
International classification
Abstract
An apparatus attachable to an extension ladder is provided having a single leg extendable in a direction perpendicular and adjacent to the two lowest rungs of an extension ladder, a channel bar sized to receive a substantial length of a lowest rung of the ladder, and a hook for latching onto a next to lowest rung of the ladder. A foot pivotally mounted to the leg at one end thereof supports the leg onto or at least partially into a level or non-level surface. A step member extends from the leg at an angle. When the ladder is extended upwards by a user, a removable arm member is received through a holder of the leg to lie against a user's leg to provide stability and prevent spinning. The apparatus when attached to the lowest two rungs elevates the ladder to be non-contact with the level or non-level surface.
Claims
1. An apparatus configured to attach to an extension ladder, said extension ladder having two elongated parallel sides and rungs extending between said sides, and said extension ladder having a lower portion and an upper portion movable with respect to said lower portion to raise or lower a top end of the extension ladder, said apparatus comprising: a single leg having members configured to latch the leg onto a plurality of adjacent rungs of said rungs of said ladder by each of said members being configured to engage, between said sides of said ladder, onto an exterior of first and second rungs of said plurality of adjacent rungs, wherein the leg has a major length configured to extend parallel to a major length of the sides of said ladder; a first of said members is non-adjustably fixed in position relative to said leg, and said first of said members has a channel, and said first of said members is configured to receive said first rung engaged with said first of said members along a major length of said channel, in which said major length of said channel extends perpendicular to said major length of said leg, a second of said members is configured to receive said second rung; a single foot mounted to one end of said leg to pivot about an axis of rotation parallel to said major length of said channel, in which said foot is configured to support said leg upon a level or non-level surface such that said leg solely supports a bottom end of said ladder, via said foot, in an elevated position above said level or non-level surface with said leg latched by said members to said ladder, wherein said first of said members is a closest one of said members to said foot, and said major length of said leg is non-adjustable; a single shaft removeably attached to said leg between said foot and said closest one of said members to said foot, in which a major length of said shaft is configured to extend away from said major length of said leg and a major plane of said ladder to allow a user to stabilize said leg above the level or non-level surface so that said shaft prevents uncontrolled spinning of the ladder during raising or lowering movement of said upper portion of the ladder with respect to said lower portion of the ladder when said shaft is attached to said leg and said leg is latched to said ladder and said foot supports said leg upon said level or non-level surface; a step member attached to said leg between said foot and said closest one of said members to said foot, said step member configured to provide a step configured to support a user climbing or descending the ladder when said leg is latched by said members to said ladder and said foot supports said leg upon said level or non-level surface; and when the apparatus is latched to said ladder, said step member and said leg are configured to pivot together as said ladder pivots about said axis of rotation in order to horizontally orient said step as said ladder is angled and said foot supports said leg upon said level or non-level surface.
2. The apparatus according to claim 1 wherein said members for latching said leg to said ladder operate independent of said shaft.
3. The apparatus according to claim 1 wherein said shaft is movable with respect to said leg to position said shaft from being a safety hazard during ladder usage.
4. The apparatus according to claim 1 wherein said leg is configured at least approximately centered between the sides of said ladder when said members latch said leg onto said plurality of adjacent rungs of said rungs of said ladder.
5. The apparatus according to claim 1 wherein said foot has a bottom comprising a gripping surface and a pick portion, and said foot is pivotal about said axis of rotation to select one of said gripping surface or said pick portion for application to said level or non-level surface, in which selection of said pick portion positions said pick portion into a depth below said level or non-level surface, and selection of said gripping surface applies said gripping surface directly onto said level or non-level surface.
6. The apparatus according to claim 1, further comprising said step member having a major top surface, said step member configured to extend away from said leg at a first angle so that pivoting said leg backwards relative to said axis of rotation pivots said step member upwards relative to said level or non-level surface to enable the major top surface of said step member to be horizontal, said major top surface configured to be horizontal when the major length of said ladder and the major length of said leg are substantially angled with respect to horizontal.
7. The apparatus according to claim 1, further comprising a holder attached to said leg, wherein said shaft is removably attached to said leg by said holder.
8. The apparatus according to claim 1 wherein said channel is configured to extend at least half of a distance between said sides of the ladder when said members latch said leg onto said plurality of adjacent rungs of said rungs of said ladder.
9. A system configured to elevate an extension ladder, said extension ladder having two elongated parallel sides and rungs extending between said sides, said system comprising: a single leg having rung engaging members configured to secure the leg onto a plurality of adjacent rungs of said rungs of said ladder by each of said members being configured to engage, between said sides of said ladder, onto an exterior of first and second rungs of said plurality of adjacent rungs, the first rung being a bottom-most rung of said rungs, wherein the leg has a major length configured to extend parallel to a major length of the sides of said ladder; a first of said members is non-adjustably fixed in position relative to said leg, and said first of said members has a channel, and said first of said members is configured to receive said first rung engaged with said first of said members along a major length of said channel, in which said major length of said channel extends perpendicular to said major length of said leg, a second of said members is configured to receive said second rung; a single foot mounted to one end of said leg to pivot about an axis of rotation parallel to said major length of said channel, in which said foot is configured to support said leg upon a level or non-level surface such that said leg solely supports a bottom end of said ladder, via said foot, in an elevated position above said level or non-level surface with said leg latched by said members to said ladder, wherein said first of said members is a closest one of said members to said foot, and said major length of said leg is non-adjustable; a first non-rung engaging member consisting of a single shaft removeably attached to said leg between said foot and said closest one of said members to said foot, in which a major length of said shaft is configured to extend away from said major length of said leg and a major plane of said ladder to allow a user to stabilize said leg above the level or non-level surface so that said shaft prevents uncontrolled spinning of the ladder during raising or lowering movement of an upper portion of the ladder with respect to a lower portion of the ladder when said shaft is attached to said leg and said leg is latched to said ladder and said foot supports said leg upon said level or non-level surface; a second non-rung engaging member consisting of a step member attached to said leg between said foot and said closest one of said members to said foot, said step member configured to provide a step configured to support a user climbing or descending the ladder when said leg is latched by said members to said ladder and said foot supports said leg upon said level or non-level surface; and when the leg is latched to said ladder, said step member and said leg are configured to pivot together as said ladder pivots about said axis of rotation in order to horizontally orient said step as said ladder is angled and said foot supports said leg upon said level or non-level surface.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) The foregoing and other objects, features and advantages of the invention will become more apparent from a reading of the following description in connection with the accompanying drawings in which:
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DETAILED DESCRIPTION OF THE INVENTION
(9) Referring to
(10) A hook 18 has a hook portion 18a extending to a straight portion 18b. The straight portion 18b extends through a hole 20 in the leg 12, and end 18c of the straight portion 18b is threaded for about 3 inches from its end so that a wing nut 21 can be screwed onto such end 18c. The hook 18 may be J-shaped and sized to receive a rung of a typical ladder in hook opening 18d, which extends from a hook end segment 18e and the part of the straight portion 18b opposite hook end segment 18e. A washer 21a is provided along straight portion 18b between leg 12 and nut 21. The wing nut 21 is used to enable hook 18 to latch a rung against leg 12 when received in hook portion 18a, and thus clamp hook 18 onto the rung. The interior width of hook opening 18d is equal to (or slightly more than) the width of a typical rung, such as 1 inches, and end segment 18e may be about 1 inch long or other length sufficient to capture a rung in opening 18d. For example, hook 18 may be a stainless steel J-bolt which is inch diameter, and bent to provide a hook as shown in the figures. Hole 20 of leg 12 is slightly larger in diameter than the diameter of hook 18 so that the straight portion 18b is movable longitudinally there through so as to enable capture and release of a rung by adjustment of nut 21. When a rung of a ladder is latched to leg 12 by hook 18, the nut 21 is hand tightened against leg 12 via washer 21a. The hole 20 for hook 18 is spaced a distance from the bottom of channel 16 of channel bar 14 so that when the channel 16 of bar 14 receives a lowest rung of a lower ladder portion of the extension ladder the hook 18 can receive and retain the next to lowest rung of the ladder, as shown for example in
(11) The channel bar 14 and hook 18 are members dimensioned to receive the two lowest rungs of a ladder along their respective exterior. For example, in the case of an extension ladder having rungs that are D-shaped in cross-section, i.e., a convex circular bottom and a horizontal top, the width along the rung's top may be 1 to 1 inches, the rung's height from bottom to top may be 1 inches, and the rung's length between two ladder's legs may be at or about 12 to 18 inches. In this example, channel bar 14 and hook 18 of apparatus 10 may have, for example, the following dimensions: hook opening 18d interior width at or approximately 1 inches in order to capture a rung; channel 16 of 1 inches to 2 inches in width (preferably 1 13/16 inches); and channel bar 14 length at or greater than 10 inches, but less than 15 inches (preferably at or approximately 10 inches). Thus, the same one of apparatus 10 can be used with a variety of different ladders of the same or different manufacturers having D-shaped rungs, or other cross-sectional shaped rungs (e.g., circular, rectangular, square, etc. . . .) having at or about 1 inches rung height, and other dimensions in or about the above stated ranges. The spacing between two adjacent rungs, as in the case of the lowest two rungs of a ladder, is generally the same between different extension ladders. The apparatus 10 may have its channel bar 14 and hook 18 sized to accommodate still other ladders (i.e., extension or non-extension types having only two legs for supporting the ladder upon a surface), so long as the two lowest ladder rungs have an exterior that can engage (lock, latch, or clamp) apparatus 10 via such rungs into channel bar 14 and hook 18 as shown for example of rungs 40a and 40b in
(12) A foot 22 is pivotally mounted to end 12a of leg 12. The foot 22 may be a typical swivel foot as used at the bottom of one of the legs of a typical extension ladder. Preferably, foot 22 has base or bottom wall or surface 23 with non-skid material 23a as typical of an extension ladder to assist in griping a surface, such as corrugated or grooved rubber. Extending upwards from the sides of the base 23 are two parallel flanges or triangular walls 24 and 25. A bolt, shaft, or pin 27 passes through a hole 28a of wall 24 (or 25), through hole 26 in each side 12d and 12c of leg 12, and then through a hole 28b of wall 25 (or 24). The two ends of bolt 27 are threaded and each has a nut 27a retaining the foot 22 onto leg 12 while enabling the foot to swivel or pivot as desired about an axis of rotation defined by the center through the length of bolt 27. One or both nuts 27a may be tightened as desired to lock the pivot position of leg 12 with respect to foot 22, and untightened to allow the foot to freely pivot about its axis of rotation about bolt 27. Such axis of rotation may be parallel to a dimension of the length of channel bar 14. For example, each of the hole 26 of leg 12 may be centered about inches from leg end 12a. Foot 22 helps prevent apparatus 10 from kicking out when apparatus 10 is attached to a ladder and presented upon a surface at a desired tilt with the ladder.
(13) A stop or spacer 29 is attached to side 12e of leg 12 above the foot 22 so that interior of the bottom wall of foot 22 will abut stop 29 when the foot is pivoted (or rotated) against stop 29, so that such stop 29 thereby provides a stopper which stops the top of foot 22, such as 1 inch, away from leg 12. The foot 22 when so pivoted, base wall 23 lies at least approximately parallel with leg side 12e, enabling the back 22a of foot 22, sometimes called an ice pick, to be used to anchor apparatus 10 into a depth below a surface when needed for support, such as digging into ice, dirt, or other such material, such as shown in
(14) A step member 30 is attached to leg 12 between channel bar 14 and foot 22 by two extension members or flanges 31 which extend from along sides 12c and 12d, respectively. Members 31 are attached to leg 12 at a downward angle 32, such as 18 degrees, with respect to the normal 33 of a dimension extending along the leg's linear length between ends 12a and 12b of leg 12, as best shown in
(15) The attachment of step member 30 to leg 12 by members 31 at angle 32 is such that when leg 12 is rotated in a forward direction indicated by arrow 35 (
(16) The leg 12, bar 14, stop 29, members 30, 31, and 34, are preferably made of aluminum, and hook (or J-bolt) 18, washer 21a, and wing nut 21, are preferably made of stainless steel. Other materials may be used, in which weight bearing components, e.g., leg 12 and bar 14, are of material suitable for sustaining loads when present upon of a ladder. Foot 22 may be a commercially available ladder foot made of steel with a rust resistant coating. Bolt 27 and nuts enabling foot pivotal attachment to leg 12 may also be the same as those in attaching a typical swivel type foot to an extension ladder. Leg 12, bar 14, hook 18, stop 29, foot 22, members 30, 31, and 34 are attached as described above and shown in
(17) The attachment of apparatus 10 to a typical extension ladder 36 is best shown in the examples of
(18) The ladder 36 when used is on a tilt such as shown in
(19) Step member 30 has two functions. First, the step member 30 may be used for seating the foot 22 of apparatus 10 onto or at least partially into a surface (such as the ground) by the user applying with one of his or her feet downward force upon the stepping surface of step member 30 with the other one of his or her feet upon such surface. Typically, without the apparatus 10, such seating is performed using the lowest rung of the ladder, but here due to the lowest rung's increase height from the ground (or other surface) with attached apparatus 10, step member 30 is used. Ladder 36 is usable without such seating, but seating of the assembly of apparatus 10 and ladder 36 is preferred to reduce the chance of slippage of the assembly during use. Second, step member 30 is used as a step to assist a user in climbing or ascending the ladder 36, as shown for example in
(20) Along the bottom of the two legs 39 of lower ladder portion 38 may be swivel feet which are not used when apparatus 10 is attached to ladder 36. As such, the length along leg 12 from channel bar 14 to foot 22 is sufficient to elevate the two legs 39 of lower ladder portion 38 (and its swivel feet, if present) a distance from the level or non-level surface (and thus the ladder is non-contact with such surface). In other words, leg 12 extends from channel bar 14 to the bottom 23 of foot 22 further than the distance of the lowest rung along the ladder's two legs 39 to lowermost part or end of the ladder. Ladder 36 with apparatus 10, attached via only rungs 40a and 40b, may be moved to any level or non-level surface as desired without any modification (e.g., height adjustment) or removal of apparatus 10, since the foot 22 can pivot and engage such surface either along material 23a, or by digging into the surface via foot's back angled portion 22a, as needed.
(21) In the example of
(22) The ladder apparatus 10 distributes all weight of ladder 36 to one point down leg 12, thereby providing a single support attachment for the ladder. This is facilitated by channel bar 14 extending substantially the extent of rung 40a. Preferably, leg 12 is centrally (or at least approximately centrally) located between legs 39 of the lower portion behind rungs 40a and 40b, so that channel bar 14 and hook 18 are centrally (or at least approximately centrally) positioned along their respective rungs to promote ladder 36 stability when used.
(23) Apparatus 10 is thus different from ladder levels, as described earlier, which distributes all weight of the ladder to two points along a surface. In other words, the weight of the ladder is distributed down both legs to the ground in which one or both of the legs are extended so that the ladder is level or approximately level. The ladder leveler devices of U.S. Pat. Nos. 4,984,655 and 5,121,813 utilize only rungs of a ladder are designed to distribute only part of the ladder weight along one side (i.e., leg) of a ladder, thus effectively extending one of the ladder's two legs. If devices of U.S. Pat. Nos. 4,984,655 and 5,121,813 were instead attached to a ladder to support the entire weight of the ladder on a surface, such would be extremely problematic due to inherent resultant ladder instability due to the manner in which their devices clamp onto the ladder. Ladder instability is undesirable since its can cause the ladder to tip as weight of a person is applied or shifted when present upon the ladder or when the body of limbs of a person on the ladder is extended from the ladder. Thus, not until the present invention has a single leg ladder support been safely attainable.
(24) Due the ladder apparatus 10 distributing all weight of ladder 36 to one point down leg 12 to its foot 22, when upper portion of the ladder is extended from the lower portion as typically manually performed by a user pulling on a rope 41a attached near the bottom of the upper portion which is fed through a pulley 41b attached near the top of the lower ladder portion, would cause the ladder to undesirably spin or rotate about leg 12 and foot 22 causing the user to lose control and possible result in a dangerous situation. To avoid this situation, an arm member 42 is provided as shown in
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(26) To stabilize ladder 36 when ladder portion 37 is being so extended, and thereby prevent spin of the ladder about leg 12 and foot 22 upon or in a level or non-level surface the arm member abuts a generally stationary member (i.e., a separate an external member apart from apparatus 10) provided by the user's leg 47a lying against arm member 42, such as illustrated in
(27) Preferably, anything capable of sliding into the opening 45 of holder 44 may be used to prevent spin of ladder 36 and attached apparatus 10 for stabilizing the ladder when the upper ladder portion 37 is moved in a controlled manner with respect to lower ladder portion 38. This allows a user, such as a contractor, to use anything in a pinch, such as dowel rod, long screw driver, jack handle, tree branch, etc., as one of arm member 42. Preferably, a dowel rod painted florescent color, such as orange, is used. For example, the dowel may be about 24 inches in length, and 1 inch in diameter. The color facilitates locating the arm member 42 on a job site.
(28) As described above, with the arm member 42 providing an extension inserted in (and preferably through) holder 44, the arm member 42 extends from leg 12 at an angle (non-zero) to go against the user's leg 47a, and stabilizes the ladder, holding it square with respect to a building 51 in the example of
(29) The apparatus 10 may be provided in a kit with or without arm member 42.
(30) From the foregoing description, it will be apparent that an apparatus, attachment, and method of using such apparatus, providing a single support to an extension ladder enabling the ladder to be use on level and non-level surfaces has been provided. Variations and modifications of the herein described apparatus, attachment, and method for implementing the invention will undoubtedly suggest themselves, to those skilled in the art. For example, other dimensions of components described herein may be used. Accordingly the foregoing description should be taken as illustrative and not in a limiting sense.