Title:
Ladder platform
Document Type and Number:
United States Patent 3899045
Abstract:
A safety platform for conventional ladders is disclosed. The platform has a generally horizontally disposed base and an integral, generally vertically disposed back and is adapted for facile mounting and dismounting on the ladder. The front portion of the base is bent downwardly to fit over a rung of the ladder. An angle member, adjustably mounted on the undersurface of the base, is spaced to the rear of the front portion of the base and the rung so as to prevent generally, horizontal, relative movement between the base and the rung. The upper portion of the back is curved, in a generally extended hook-like shape, to fit over the adjacent upper rung of the ladder so as to prevent generally horizontal, relative movement between the back and the upper rung. A safety latch, gravity biased to a latched position, prevents relative movement between the platform and the ladder, and thus assures that the platform cannot be accidentally dislodged from the ladder. The latch includes a handle and an arm having one end pivotally mounted on the curved upper portion of the back. When in latched position, the other end of the latch arm abuts the rearward facing surface of the back at a point spaced below the upper rung. The latch may be selectively swung away from its latched position so as to permit the facile removal of the platform from the ladder. The base is perforated so that dirt and the like will not accumulate thereon. The curved upper portion of the back includes a plurality of fingers which permit a variety of containers for tools and the like to be supported therefrom.
Inventors:
Geisel, Anthony (Chicago, IL)
Rohowsky, Bohdan (Chicago, IL)
Rohowsky, Bohdan (Chicago, IL)
Plaque It!
Sponsored by: Flash of Genius |
Application Number:
05/466788
Publication Date:
08/12/1975
Filing Date:
05/03/1974
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Referenced by:
Export Citation:
Primary Class:
International Classes:
E06C7/16; E06C7/00; E06C7/00; E06C5/32
Field of Search:
182/121,120,122 248/238,210
US Patent References:
Primary Examiner:
Machado, Reinaldo P.
Attorney, Agent or Firm:
Molinare, Allegretti, Newitt & Witcoff
Claims:
What is claimed is
1. An improved safety platform adapted to be used with a generally vertically disposed ladder having side rails and a plurality of rungs, including a first rung and a second rung positioned immediately above the first rung comprising:
2. The improved safety platform described in claim 1 wherein the back member and base member are integral; and wherein an acute angle is formed between the plane of the base member and the plane of the back member.
3. The improved safety platform described in claim 1 wherein a portion of the latching arm extends through a slot formed in the distal end of the second extended portion of the back member; wherein the second end of the latching arm includes means for preventing the second end of the latching arm from passing through the slot; and wherein the latching arm includes a handle.
4. The improved safety platform described in claim 1 wherein a portion of the latching arm extends through a slot formed in the distal end of the second extended portion of the back member; wherein the second end of the latching arm includes means for preventing the second end of the latching arm from passing through the slot; wherein the latching arm includes a handle; wherein a portion of the base member is perforated so as to prevent the accumulation of dirt and the like on the base member; wherein the back member and base member are integral; wherein an acute angle is formed between the plane of the base member and the plane of the back member; and wherein the distal end includes means for supporting tools and the like.
1. An improved safety platform adapted to be used with a generally vertically disposed ladder having side rails and a plurality of rungs, including a first rung and a second rung positioned immediately above the first rung comprising:
2. The improved safety platform described in claim 1 wherein the back member and base member are integral; and wherein an acute angle is formed between the plane of the base member and the plane of the back member.
3. The improved safety platform described in claim 1 wherein a portion of the latching arm extends through a slot formed in the distal end of the second extended portion of the back member; wherein the second end of the latching arm includes means for preventing the second end of the latching arm from passing through the slot; and wherein the latching arm includes a handle.
4. The improved safety platform described in claim 1 wherein a portion of the latching arm extends through a slot formed in the distal end of the second extended portion of the back member; wherein the second end of the latching arm includes means for preventing the second end of the latching arm from passing through the slot; wherein the latching arm includes a handle; wherein a portion of the base member is perforated so as to prevent the accumulation of dirt and the like on the base member; wherein the back member and base member are integral; wherein an acute angle is formed between the plane of the base member and the plane of the back member; and wherein the distal end includes means for supporting tools and the like.
Description:
BACKGROUND OF THE INVENTION
The present invention relates to an improved safety platform, and more particularly to an improved safety platform adapted to be used with and attached between two adjacent rungs of a generally vertically disposed, conventional ladder.
In the past, various different types of platforms have been utilized with ladders to permit a person working on a ladder to stand without the usual foot discomfort. Exemplary of such prior platforms are those shown in U.S. Pat. Nos.: 169,236, issued to W. Case et al. on Oct. 26, 1875; 185,251 issued to L. D. Mason on Dec. 12, 1876; 248,014 issued to C. A. Boardman on Oct. 11, 1881; and 1,462,086 issued to P. M. Echlin on Oct. 13, 1922. While the prior platforms, as described in the foregoing patents, would appear to be capable of accomplishing their intended function, they would also appear to be relatively costly to manufacture and this would, of course, limit their present day, commercial appeal. Moreover, these prior platforms do not include any means for preventing the accidental dislodgement of the platform from a ladder. This is a serious deterrent to the successful commercialization of such platforms. Furthermore, a number of these prior platforms project out into the path of a person attempting to climb the ladder, and this would pose an obvious additional safety hazard.
In contrast, applicants have provided an improved safety platform which overcomes the defects and disadvantageous features of these prior platforms. Applicant's safety platform includes a latch that prevents accidental dislodgement of the platform from a ladder while still permitting facile attachment and detachment of the platform from a ladder. In this regard, the latch is gravity biased to its latched position and requires positive action to move the latch to a position which will permit the platform to be removed from a ladder. The latch includes means which assures that the latch will always return to its latched position whenever the latch is not being positively held away from its latched position.
The improved safety platform includes a generally horizontally disposed base and a generally vertically disposed back. The rearward edge of the base is connected with the lower edge of the back so that an acute angle is formed between the base and back. A portion of the base, adjacent to its forward edge, is bent downwardly so as to fit over a first rung of a ladder. A depending angle member is adjustably mounted on the undersurface of the base and is spaced rearwardly of the rung so as to prevent generally horizontal relative movement between the base and the ladder. The upper portion of the back is bent, in an extended generally hook shape, so as to enable it to fit over a second rung, which is immediately above the first rung, so as to prevent generally horizontal relative movement between the back and the ladder. The latch is pivotally mounted on the upper portion of the back and when in its latched position, is positioned about the second rung.
From the standpoint of market appeal, the improved safety platform of the present invention includes a number of commercially attractive and advantageous features. The platform may be made from a formed steel stamping and thus can be manufactured and marketed at a comparatively and competitively low price. The base of the platform, i.e. the portion on which a person stands, includes a number of perforations which prevents an accumulation of dirt and the like, provides a safe, non-skid surface, and lightens the weight of the platform. The spacing between the forward, bent downward portion of the base and the angle member may be adjusted so that the platform may be utilized with different ladders having a variety of rung sizes and shapes. Applicant's platform also does not project out forwardly beyond the plane of the ladder, i.e. the plane defined by the side rails and the rungs of the ladder, so that the platform will not interfere with a person climbing the ladder. A plurality of rearwardly facing fingers are formed on the distal end of the upper portion of the back, and these fingers may be utilized to support, out of the way of the feet or legs of a person standing on a platform, a variety of containers or holders for tools and the like.
Accordingly, it is the primary object of the present invention to provide an improved safety platform for use on and attachment between two adjacent rungs of a conventional ladder. A related object of the present invention is to provide an improved safety platform of the type described wherein the platform includes means for preventing relative movement between the platform and the rungs of the ladder and means for positively preventing accidental dislodgement or detachment of the platform from the ladder.
Another object of the present invention is to provide an improved safety platform of the type described wherein the platform does not project forwardly of a plane defined by the side rails and rungs of the ladder and wherein the base includes a plurality of perforations which prevent the accumulation of dirt and the like on the base, provide a non-skid surface and reduce the weight of the platform.
Still another object of the present invention is to provide an improved safety platform of the type described which can be utilized with ladders having different sized and dimensioned rungs. A related object of the present invention is to provide an improved safety platform of the type described wherein the platform includes means for supporting a plurality of tools and the like such that the tool and the like do not interfere with a person standing or working on the platform.
These and other objects and advantages of the present invention will become apparent from the following description of the preferred embodiment of the invention, described in connection with the accompanying drawings.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view of the improved safety platform of the present invention shown mounted between two adjacent rungs of a conventional ladder.
FIG. 2 is a front view of the improved safety platform of the present invention shown mounted on a conventional ladder.
FIG. 3 is a vertical cross-sectional view of the improved safety platform of the present invention, taken along line 3--3 of FIG. 1.
FIG. 4 is a perspective view of the improved safety platform of the present invention.
FIG. 5 is a perspective view of a container which may be used for holding tools and the like and which may be supported on the improved safety platform of the present invention.
FIG. 6 is a perspective view of a device which may be used for holding tools and the like and which may be supported on the improved safety platform of the present invention.
FIG. 7 is a perspective view of another container which may be used for holding tools and the like and which may be supported on the improved safety platform of the present invention.
FIG. 8 is a perspective view of still another container which may be used for holding tools and the like and which may be supported on the improved safety platform of the present invention.
Throughout the various figures of the drawings, the same reference numerals will be used to designate the same parts of the improved safety platform of the present invention. Moreover, when the terms "right", "left", are used herein, it is to be understood that these terms have reference to the structure shown in the drawings as it would appear to a person viewing the drawings. Similarly when the terms "front", "forward", "rear", "rearward", "upper" or "lower" are used herein, it is to be understood that these terms have reference to the improved safety platform of the present invention as mounted on a ladder. In this regard, the "front" or "forward" edge of the platform is the edge which is adjacent to or closest to the side of the ladder facing away from the ground.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIGS. 1 - 4, the improved safety platform of the present invention is shown generally at 12 and as noted above, is adapted to be supported by and attached between adjacent, upper and lower rungs 14 and 16 of a convention ladder 18 having side rails 22 and 24.
The platform 12 includes a base member 26 and a back member 28. When the base and back members 26 and 28 are integrally made from a single piece of relatively heavy gauge steel that is bent so that the plane of the back member 28 forms an acute angle, preferably about 70°-75°, with the plane of the base member 26. Side flanges 32 and 34 are formed along the side edges of the base and back members and project upwardly and forwardly, respectively a relatively short distance from the planes of these members. The central portion of the base member 26 has a plurality of perforations 36 therein which can be formed by means of a stamping operation or by utilization of an insert of expanded metal. The perforations 36 in the base member 26 prevent the accumulation of dirt and the like which might otherwise accumulate on the base member 26, when the platform is attached to the ladder 18, as well as providing a non-skid surface.
A central, rectangular portion of the back member is cut away as shown at 38. The cut away portion 38 in the back member 28 reduces the weight of the platform, without reducing its strength. A pair of re-enforcing angle members 42 and 43 extend between the forward end 44 of the base member 26 and the upper end 45 of the back member 28, and are secured at the sides of the members 26 and 28 by rivets or welding.
The forward end 44 of the base member is bent downwardly so that the bent portion 46 forms an angle approximately 90° with the plane of the base member 26. An angle member 48 is mounted on and depends from the undersurface of the base member 26 adjacent to the forward end 44 of the member 26, with the spacing between the angle member 48 and the bent portion 46 being slightly larger than the maximum cross-sectional dimension of the rung 16.
So as to enable the safety platform 12 to be utilized with ladders having different sized and shaped rungs, the position of the angle member 48 may be adjusted vis-a-vis the bent portion 46. In this regard a pair of slots 52 and 54 are formed in the base member 26, adjacent to the forward end 44, and adjacent to and aligned with the side flanges 32 and 34. A pair of bolts 56 and 58 extend through the slots 52 and 54, respectively, and through aligned holes drilled in the angle member 48. Wing nuts 62 and 64 are threaded on the ends of the bolts.
By adjusting the spacing between the bent portion 46 and the angle member 48 so that the angle member abuts the rung 16, relative horizontal movement between the ladder 18 and the base member 26 is prevented. As best shown in FIG. 2, the bent portion 46 of the base member 26 has sufficient length, in the direction parallel to the longitudinal axes of the rungs, relative horizontal, side to side movement cannot occur between the base member 26 and the ladder 18, and the rung 16. Furthermore since the bent portion 46 does not project forwardly beyond a plane defined by the rungs 14 and 16 and the side rails 22 and 24 of the ladder 18, a person can climb up or down the ladder, and around the platform 12, without having the platform unduly interfere with his climbing.
The upper end portion 45 of the back member 28 is bent in a rearwardly directed, generally "U" or hook shape. This end portion 45 has a radius of curvature which is greater than the maximum cross-sectional dimension of the rung 14, or for that matter, the maximum cross-sectional dimension of the rungs on all commercially available ladders, so that the end portion 45 can easily fit over and around the rung 14. The distal end 68 of the end portion 45 is formed in a plane which is essentially parallel to the plane of the back member 28.
As best shown in FIGS. 2 and 4, four rearwardly and upwardly directed fingers 72 have been stamped from the distal end 68. These fingers 72 are symmetrically arranged, a pair on each side, about a centrally disposed rectangular slot 74 cut in the distal end 68, and are utilized to support a variety of containers or supports for tools and the like. In this regard, containers 76, 78 and 82 as illustrated in FIGS. 5, 7 and 8 may be supported from the fingers 72. More specifically, each of the containers 76, 78 and 82 have a plurality of slots or openings 84 formed in their rear walls 86. These openings 84 are sized and spaced so that the fingers 72 can fit therethrough. As shown in FIG. 5, container 76 has four openings 84 designed and arranged to receive the four fingers 72. In contrast, the containers 78 and 82 have only two slots 84 and are, of course, designed and arranged to be supported by a pair of two fingers 72. FIG. 6 shows another type of attachment 88 which utilizes spring clips 90 to releasably secure tools or the like. The attachment 88 includes a pair of slots 91 in its back 92 adapted to receive a pair of the fingers 72.
Referring now again to FIGS. 1, 2 and 4, a latch 94 is mounted on the platform 12 and is utilized to releasably latch or lock the platform 12 to the ladder 18. A pair of ears 96 and 98 are secured, by welding, to the upper portion 45. These ears 96 and 98 are spaced apart and include aligned, horizontally disposed bores which are adapted to receive a pin 102. A combined latch arm and handle 103 has an end 104 which has a hole drilled therein. The end 104 is disposed between the ears 96 and 98 so that the hole therein is aligned with the bores in the ears and so that the pin 102 can be inserted through the aligned hole and bores. This pin and ear arrangement is, thus, utilized to pivotally mount the end 104 of the combined handle and latch arm 94. The combined latch arm and handle 103 has a handle 106 on its end, opposite the end 104, and this handle 106 is used to manually pivot the combined latch arm and handle about the pin 102. A curved arm portion 108, integrally formed with the combined latch arm and handle 103 has a radius of curvature, about the center line of the pin 102, greater than the maximum cross-sectional dimension of the rung 14 so that the arm portion 108 does not contact or engage the rung 14 when the platform 12 is mounted on the ladder 18 as shown in FIG. 1. The arm portion 108 extends through the slot 74 and is arranged so that its distal end 112 abuts the rearward facing surface of the back member 28 when the combined latch arm and handle 103 is not being manually held away from this position. In other words, the combined latch arm and handle 103 is gravity biased toward the position shown in FIG. 1 and must be manually moved up, away from that position in order to remove the platform 12 from the ladder 18. This is an important safety feature since the use of this combined latch arm and handle, it is impossible for accidental dislodgement or detachment of the platform 12 from the ladder 18. A pin 114 is press-fit into a hole formed in the end 112 of the arm portion 108. The length of this pin 114 is greater than the width of the slot 74, and thus, the pin prevents the end 112 from being removed from the slot. This assures that the combined latch arm and handle 104 will always be gravity biased into a locking or latching position.
When it is desired to mount the improved safety platform 12 on a ladder, such as ladder 18, the forward end 44 of the base member 26 and the upper end portion 45 of the back member 28 are set down on the rungs 16 and 14, respectively. More specifically, the forward end 44 is placed down over the rung 16 while the upper end portion 45 of the platform 12 is placed over the rung 14. During this time the combined latch arm and handle 103 must be rotated counterclockwise about the pin 102 until the pin 114 engages the distal end 68. As soon as the platform 12 is positioned over the rungs 14 and 16, the handle 94 may be released so that it will fall, under the influence of gravity, to its latched position, such as shown in FIG. 1, wherein the end of the arm 112 of the arm 108 abuts the rearward facing surface of the back member 28. To assure that the platform 12 will remain relatively stationary with respect to the ladder 18, the position of the angle member 48 may be adjusted relative to the bent portion 46 by loosening the wing nuts 62 and 64 and sliding the angle member 48 forward until the rung 16 is clamped between the angle member and the bent portion 46. Thereafter the wing nuts 62 and 64 are, of course, retightened.
In view of the foregoing, it is apparent that the improved safety platform of the present invention affords many desirable, commercially attractive features. One of these features is the inclusion of the latch 94 which is designed such that it is always in its latched position unless a person positively holds it away from its latched position. Another important feature, from the standpoint of commercialization, is the perforations in the base member 26 which forms a skid-proof surface and permits dirt and the like to fall through the base member. Furthermore, the safety platform of the present invention has a design which facilitates relatively inexpensive manufacture and this, of course, is a significant advantage in commercializing the platform.
It will also be apparent to those having ordinary skill in this art that various features of the embodiment of the safety platform disclosed herein may be modified. For example, additional fingers, such as fingers 72, could be utilized and the base and back members could be made from separate pieces of metal and welded together. Therefore, since the invention disclosed herein may be embodied in other specific forms without departing from the spirit or central characteristics thereof, the preferred embodiment of the invention described herein is therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the claims, rather than by the foregoing description, and all changes which come within the meaning and the range of equivalency of the claims are therefore intended to be embraced therein.
The present invention relates to an improved safety platform, and more particularly to an improved safety platform adapted to be used with and attached between two adjacent rungs of a generally vertically disposed, conventional ladder.
In the past, various different types of platforms have been utilized with ladders to permit a person working on a ladder to stand without the usual foot discomfort. Exemplary of such prior platforms are those shown in U.S. Pat. Nos.: 169,236, issued to W. Case et al. on Oct. 26, 1875; 185,251 issued to L. D. Mason on Dec. 12, 1876; 248,014 issued to C. A. Boardman on Oct. 11, 1881; and 1,462,086 issued to P. M. Echlin on Oct. 13, 1922. While the prior platforms, as described in the foregoing patents, would appear to be capable of accomplishing their intended function, they would also appear to be relatively costly to manufacture and this would, of course, limit their present day, commercial appeal. Moreover, these prior platforms do not include any means for preventing the accidental dislodgement of the platform from a ladder. This is a serious deterrent to the successful commercialization of such platforms. Furthermore, a number of these prior platforms project out into the path of a person attempting to climb the ladder, and this would pose an obvious additional safety hazard.
In contrast, applicants have provided an improved safety platform which overcomes the defects and disadvantageous features of these prior platforms. Applicant's safety platform includes a latch that prevents accidental dislodgement of the platform from a ladder while still permitting facile attachment and detachment of the platform from a ladder. In this regard, the latch is gravity biased to its latched position and requires positive action to move the latch to a position which will permit the platform to be removed from a ladder. The latch includes means which assures that the latch will always return to its latched position whenever the latch is not being positively held away from its latched position.
The improved safety platform includes a generally horizontally disposed base and a generally vertically disposed back. The rearward edge of the base is connected with the lower edge of the back so that an acute angle is formed between the base and back. A portion of the base, adjacent to its forward edge, is bent downwardly so as to fit over a first rung of a ladder. A depending angle member is adjustably mounted on the undersurface of the base and is spaced rearwardly of the rung so as to prevent generally horizontal relative movement between the base and the ladder. The upper portion of the back is bent, in an extended generally hook shape, so as to enable it to fit over a second rung, which is immediately above the first rung, so as to prevent generally horizontal relative movement between the back and the ladder. The latch is pivotally mounted on the upper portion of the back and when in its latched position, is positioned about the second rung.
From the standpoint of market appeal, the improved safety platform of the present invention includes a number of commercially attractive and advantageous features. The platform may be made from a formed steel stamping and thus can be manufactured and marketed at a comparatively and competitively low price. The base of the platform, i.e. the portion on which a person stands, includes a number of perforations which prevents an accumulation of dirt and the like, provides a safe, non-skid surface, and lightens the weight of the platform. The spacing between the forward, bent downward portion of the base and the angle member may be adjusted so that the platform may be utilized with different ladders having a variety of rung sizes and shapes. Applicant's platform also does not project out forwardly beyond the plane of the ladder, i.e. the plane defined by the side rails and the rungs of the ladder, so that the platform will not interfere with a person climbing the ladder. A plurality of rearwardly facing fingers are formed on the distal end of the upper portion of the back, and these fingers may be utilized to support, out of the way of the feet or legs of a person standing on a platform, a variety of containers or holders for tools and the like.
Accordingly, it is the primary object of the present invention to provide an improved safety platform for use on and attachment between two adjacent rungs of a conventional ladder. A related object of the present invention is to provide an improved safety platform of the type described wherein the platform includes means for preventing relative movement between the platform and the rungs of the ladder and means for positively preventing accidental dislodgement or detachment of the platform from the ladder.
Another object of the present invention is to provide an improved safety platform of the type described wherein the platform does not project forwardly of a plane defined by the side rails and rungs of the ladder and wherein the base includes a plurality of perforations which prevent the accumulation of dirt and the like on the base, provide a non-skid surface and reduce the weight of the platform.
Still another object of the present invention is to provide an improved safety platform of the type described which can be utilized with ladders having different sized and dimensioned rungs. A related object of the present invention is to provide an improved safety platform of the type described wherein the platform includes means for supporting a plurality of tools and the like such that the tool and the like do not interfere with a person standing or working on the platform.
These and other objects and advantages of the present invention will become apparent from the following description of the preferred embodiment of the invention, described in connection with the accompanying drawings.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view of the improved safety platform of the present invention shown mounted between two adjacent rungs of a conventional ladder.
FIG. 2 is a front view of the improved safety platform of the present invention shown mounted on a conventional ladder.
FIG. 3 is a vertical cross-sectional view of the improved safety platform of the present invention, taken along line 3--3 of FIG. 1.
FIG. 4 is a perspective view of the improved safety platform of the present invention.
FIG. 5 is a perspective view of a container which may be used for holding tools and the like and which may be supported on the improved safety platform of the present invention.
FIG. 6 is a perspective view of a device which may be used for holding tools and the like and which may be supported on the improved safety platform of the present invention.
FIG. 7 is a perspective view of another container which may be used for holding tools and the like and which may be supported on the improved safety platform of the present invention.
FIG. 8 is a perspective view of still another container which may be used for holding tools and the like and which may be supported on the improved safety platform of the present invention.
Throughout the various figures of the drawings, the same reference numerals will be used to designate the same parts of the improved safety platform of the present invention. Moreover, when the terms "right", "left", are used herein, it is to be understood that these terms have reference to the structure shown in the drawings as it would appear to a person viewing the drawings. Similarly when the terms "front", "forward", "rear", "rearward", "upper" or "lower" are used herein, it is to be understood that these terms have reference to the improved safety platform of the present invention as mounted on a ladder. In this regard, the "front" or "forward" edge of the platform is the edge which is adjacent to or closest to the side of the ladder facing away from the ground.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIGS. 1 - 4, the improved safety platform of the present invention is shown generally at 12 and as noted above, is adapted to be supported by and attached between adjacent, upper and lower rungs 14 and 16 of a convention ladder 18 having side rails 22 and 24.
The platform 12 includes a base member 26 and a back member 28. When the base and back members 26 and 28 are integrally made from a single piece of relatively heavy gauge steel that is bent so that the plane of the back member 28 forms an acute angle, preferably about 70°-75°, with the plane of the base member 26. Side flanges 32 and 34 are formed along the side edges of the base and back members and project upwardly and forwardly, respectively a relatively short distance from the planes of these members. The central portion of the base member 26 has a plurality of perforations 36 therein which can be formed by means of a stamping operation or by utilization of an insert of expanded metal. The perforations 36 in the base member 26 prevent the accumulation of dirt and the like which might otherwise accumulate on the base member 26, when the platform is attached to the ladder 18, as well as providing a non-skid surface.
A central, rectangular portion of the back member is cut away as shown at 38. The cut away portion 38 in the back member 28 reduces the weight of the platform, without reducing its strength. A pair of re-enforcing angle members 42 and 43 extend between the forward end 44 of the base member 26 and the upper end 45 of the back member 28, and are secured at the sides of the members 26 and 28 by rivets or welding.
The forward end 44 of the base member is bent downwardly so that the bent portion 46 forms an angle approximately 90° with the plane of the base member 26. An angle member 48 is mounted on and depends from the undersurface of the base member 26 adjacent to the forward end 44 of the member 26, with the spacing between the angle member 48 and the bent portion 46 being slightly larger than the maximum cross-sectional dimension of the rung 16.
So as to enable the safety platform 12 to be utilized with ladders having different sized and shaped rungs, the position of the angle member 48 may be adjusted vis-a-vis the bent portion 46. In this regard a pair of slots 52 and 54 are formed in the base member 26, adjacent to the forward end 44, and adjacent to and aligned with the side flanges 32 and 34. A pair of bolts 56 and 58 extend through the slots 52 and 54, respectively, and through aligned holes drilled in the angle member 48. Wing nuts 62 and 64 are threaded on the ends of the bolts.
By adjusting the spacing between the bent portion 46 and the angle member 48 so that the angle member abuts the rung 16, relative horizontal movement between the ladder 18 and the base member 26 is prevented. As best shown in FIG. 2, the bent portion 46 of the base member 26 has sufficient length, in the direction parallel to the longitudinal axes of the rungs, relative horizontal, side to side movement cannot occur between the base member 26 and the ladder 18, and the rung 16. Furthermore since the bent portion 46 does not project forwardly beyond a plane defined by the rungs 14 and 16 and the side rails 22 and 24 of the ladder 18, a person can climb up or down the ladder, and around the platform 12, without having the platform unduly interfere with his climbing.
The upper end portion 45 of the back member 28 is bent in a rearwardly directed, generally "U" or hook shape. This end portion 45 has a radius of curvature which is greater than the maximum cross-sectional dimension of the rung 14, or for that matter, the maximum cross-sectional dimension of the rungs on all commercially available ladders, so that the end portion 45 can easily fit over and around the rung 14. The distal end 68 of the end portion 45 is formed in a plane which is essentially parallel to the plane of the back member 28.
As best shown in FIGS. 2 and 4, four rearwardly and upwardly directed fingers 72 have been stamped from the distal end 68. These fingers 72 are symmetrically arranged, a pair on each side, about a centrally disposed rectangular slot 74 cut in the distal end 68, and are utilized to support a variety of containers or supports for tools and the like. In this regard, containers 76, 78 and 82 as illustrated in FIGS. 5, 7 and 8 may be supported from the fingers 72. More specifically, each of the containers 76, 78 and 82 have a plurality of slots or openings 84 formed in their rear walls 86. These openings 84 are sized and spaced so that the fingers 72 can fit therethrough. As shown in FIG. 5, container 76 has four openings 84 designed and arranged to receive the four fingers 72. In contrast, the containers 78 and 82 have only two slots 84 and are, of course, designed and arranged to be supported by a pair of two fingers 72. FIG. 6 shows another type of attachment 88 which utilizes spring clips 90 to releasably secure tools or the like. The attachment 88 includes a pair of slots 91 in its back 92 adapted to receive a pair of the fingers 72.
Referring now again to FIGS. 1, 2 and 4, a latch 94 is mounted on the platform 12 and is utilized to releasably latch or lock the platform 12 to the ladder 18. A pair of ears 96 and 98 are secured, by welding, to the upper portion 45. These ears 96 and 98 are spaced apart and include aligned, horizontally disposed bores which are adapted to receive a pin 102. A combined latch arm and handle 103 has an end 104 which has a hole drilled therein. The end 104 is disposed between the ears 96 and 98 so that the hole therein is aligned with the bores in the ears and so that the pin 102 can be inserted through the aligned hole and bores. This pin and ear arrangement is, thus, utilized to pivotally mount the end 104 of the combined handle and latch arm 94. The combined latch arm and handle 103 has a handle 106 on its end, opposite the end 104, and this handle 106 is used to manually pivot the combined latch arm and handle about the pin 102. A curved arm portion 108, integrally formed with the combined latch arm and handle 103 has a radius of curvature, about the center line of the pin 102, greater than the maximum cross-sectional dimension of the rung 14 so that the arm portion 108 does not contact or engage the rung 14 when the platform 12 is mounted on the ladder 18 as shown in FIG. 1. The arm portion 108 extends through the slot 74 and is arranged so that its distal end 112 abuts the rearward facing surface of the back member 28 when the combined latch arm and handle 103 is not being manually held away from this position. In other words, the combined latch arm and handle 103 is gravity biased toward the position shown in FIG. 1 and must be manually moved up, away from that position in order to remove the platform 12 from the ladder 18. This is an important safety feature since the use of this combined latch arm and handle, it is impossible for accidental dislodgement or detachment of the platform 12 from the ladder 18. A pin 114 is press-fit into a hole formed in the end 112 of the arm portion 108. The length of this pin 114 is greater than the width of the slot 74, and thus, the pin prevents the end 112 from being removed from the slot. This assures that the combined latch arm and handle 104 will always be gravity biased into a locking or latching position.
When it is desired to mount the improved safety platform 12 on a ladder, such as ladder 18, the forward end 44 of the base member 26 and the upper end portion 45 of the back member 28 are set down on the rungs 16 and 14, respectively. More specifically, the forward end 44 is placed down over the rung 16 while the upper end portion 45 of the platform 12 is placed over the rung 14. During this time the combined latch arm and handle 103 must be rotated counterclockwise about the pin 102 until the pin 114 engages the distal end 68. As soon as the platform 12 is positioned over the rungs 14 and 16, the handle 94 may be released so that it will fall, under the influence of gravity, to its latched position, such as shown in FIG. 1, wherein the end of the arm 112 of the arm 108 abuts the rearward facing surface of the back member 28. To assure that the platform 12 will remain relatively stationary with respect to the ladder 18, the position of the angle member 48 may be adjusted relative to the bent portion 46 by loosening the wing nuts 62 and 64 and sliding the angle member 48 forward until the rung 16 is clamped between the angle member and the bent portion 46. Thereafter the wing nuts 62 and 64 are, of course, retightened.
In view of the foregoing, it is apparent that the improved safety platform of the present invention affords many desirable, commercially attractive features. One of these features is the inclusion of the latch 94 which is designed such that it is always in its latched position unless a person positively holds it away from its latched position. Another important feature, from the standpoint of commercialization, is the perforations in the base member 26 which forms a skid-proof surface and permits dirt and the like to fall through the base member. Furthermore, the safety platform of the present invention has a design which facilitates relatively inexpensive manufacture and this, of course, is a significant advantage in commercializing the platform.
It will also be apparent to those having ordinary skill in this art that various features of the embodiment of the safety platform disclosed herein may be modified. For example, additional fingers, such as fingers 72, could be utilized and the base and back members could be made from separate pieces of metal and welded together. Therefore, since the invention disclosed herein may be embodied in other specific forms without departing from the spirit or central characteristics thereof, the preferred embodiment of the invention described herein is therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the claims, rather than by the foregoing description, and all changes which come within the meaning and the range of equivalency of the claims are therefore intended to be embraced therein.