US3395776A - Self-locking safety support for ladders - Google Patents

Description

Aug 5, 1968 H. F. RUSSELL 3,395,776

SELFLOCKING SAFETY SUPPORT FOR LADDERS Filed March l5, 196'? 2 Sheets-Sheet l Aug- 5 1968 H. F. RUSSELL 3,395,776

SELF"LOCKING SAFETY SUPPORT FOR LADDERS Filed March 15, 1967 2 Sheets-Sheet 2 United States 3,395,776 SELF-LOCKING SAFETY SUPPORT FOR LADDERS Hilary F. Russell, 417 S. Main St., Manchester, Conn. 06040 Filed Mar. 13, 1967, Ser. No. 622,714 7 Claims. (Cl. 182-108) ABSTRACT F THE DISCLUSURE Background of inventori (I) Field of the invention.-The present invention relates to enhancing the lateral stability of ladders. More particularly, the present invention is directed to safety supports which engage the surface upon which the base of a ladder is resting to thereby -prevent lateral movement of the ladder. Accordingly, the general objects of the present invention are to provide new and improved apparatus of such character.

(2) Description of the prior art-Lateral movement of ladders has long been known as a cause of accidents. Accordingly, in the prior art, many safety devices designed for the prevention of such movement have been proposed and, in some cases, employed. These prior ait safety devices have, unfortunately, one or more deficiencies which have impaired their uesfulness.

Perhaps the most serious deficiency of prior art ladder supports involved a reluctance on the part of personnel to use the devices. This reluctance was predicated on the facts that, in transit, the support devices were usually in the way and thus caused inconvenience and often injury. The foregoing was as a result of the fact that, in most cases, the prior art support devices could not be readily detached from the side rails of the ladder. This, of course, also interfered with the storage of ladders when not in use. Reluctance t0 employ the prior art supports was also based on the fact that their use was inconvenient in that it generally required performing one or more adjustment procedures for each support; there being two supports on each ladder. Improper performance of the adjustment procedures could itself be a cause of accident since the knowledge that the ladder was equipped with a safety support often resulted in a decrease in the care exercised by the individual.

Prior art ladder supports, in addition to the disadvantages and deficiencies noted above, were also generally characterized by relatively high cost. The high cost could, in most cases, be attribute to the unnecessary complexity of the devices.

Summary of the invention Patented Aug. 6, 1968 Brief description of the drawing The present invention will become better understood and its numerous advantages will become apparent to those skilled in the art by reference to the accompanying drawing wherein like reference numerals refer to like elements in the various figures and in which:

FIGURE 1 is a side view of a first embodiment of the present invention shown installed on an extension ladder.

FIGURE 2 is a front view, taken along line 2-2 of FIGURE 1, of the embodiment of FIGURE l.

FIGURE 3 is a top view, taken along line 3-3, of the embodiment of FIGURE l.

FIGURE 4 is a view, partially in section, of the ernbodiment of FIGURE 1 taken along line 4-4 of FIG- URE 1.

FIGURE 5 depicts the embodiment of FIGURE 1 with support member disengaged and partially removed from the bracket member.

FIGURE 6 is a partial view taken in the same direction as FIGURE 5 with the support member further removed from the bracket.

FIGURE 7 is a top view taken along line 7-7 of FIG- URE 6, further showing the method of removal of the support bracket.

FIGURE 8 is a view taken in the same direction as FIGURES 2, 5 and 6 showing the support member fully removed from the bracket.

FIGURE 9 depicts a second embodiment of the present invention installed on an extension ladder.

FIGURE 10 is a view of the ground engaging foot of the embodiment of FIGURE 9.

Description of the preferred embodiments Referring now to FIGURE l, a first embodiment of the present invention is shown in its in-use position mounted on the side rail 10 of the lower section an extension ladder. The safety device of the present invention comprises a bracket member, indicated generally at 12, and a, support member, indicated generally at 14.

Bracket member 12 comprises, in the embodiment of FIGURE 1, a base plate 16 which, in the case of the ladder of wood construction shown, is permanently affixed to the ladder side rail by means of wood screws 18-18. In the case of a ladder of aluminum or magnesium construction, the ladder side rail Will be drilled through and bracket member 12 Will be permanently attached to the side rail by means of bolts. It should be noted that the holes in plate 16 are machined so as to permit countersinking of the heads of screws 18.

Bracket member 12 also comprises a retainer member 20. As may best be seen from FIGURES 3 and 4, the inner and outer surfaces of retainer member 20, when viewed in cross-section, define circular arcs of between and 180 degrees except in region 21 where a full 180 degree section is employed. The retainer member 20 is permanently attached to plate 16 at one end, for example by welding, thus leaving a gap or slot extending from the top of member 20 downwardly to region 21 between the other end of member 20 and plate 16 and defining a channel in the bracket member.

As may be seen most clearly from FIGURES 2 and 5, the upper end of retaining member 20 is provided with a locking notch 22. Adjacent its lower end and just above region 21, retaining member 20 is provided with -a cutout portion 24. A `second or lower locking notch 26 extends from cutout 24 into region 21. Cutout 24 extends from the open or unclosed end of retaining member 20 back toward the point where member 20 is welded to plate 16.

Locking notches 22 and 26 are narrower than the width of the channel in bracket member 12. The purpose of cutout 24, locking notches 22 and 26 and region 21 will become apparent from the description below.

Support member 14, as can clearly be seen from FIG- URE 1, is of generally triangular shape and, in the usual instance, will be comprised of a steel rod bent into the form of a triangle and Welded at point 28. Point 2S is intermediate of the end of the rod and thus an extension 30 is provided. Rod extension 30 is machined or forged so as to provide fiat upper and lower surfaces, these surfaces lying in parallel planes perpendicular to the plane defined by support member 14. Extension 30 is provided with a threaded hole therein.

Support member `14 also comprises a foot or pad member, indicated generally at 32, which is intended to rest upon the surface `from which the ladder extends. Foot member 32 consists of a base plate 34 and a threaded rod 36 extending upwardly therefrom. A first end of threaded rod 36 is permanently and rigidly aflixed to plate '34 by any suitable means. The second end of rod 36 engages the threads in the hole in extension 30 of support member 14 and extends therethrough. Adjustments for the terrain upon which the ladder rests may be made by merely turning rod 36 to either increase or decrease the distance between the plate 34 and the bottom of rod extension 3l).

The diameter of the rod which comprises support member 14 is such that one leg of the triangle formed thereby will Slide within the channel defined by plate 16 and retainer member 20. However, as may be seen from FIG- URE 3, the diameter of the rod is sufficiently great such that the rod cannot be removed sideways from the aforementioned channel. The rod is also grooved on both sides `as may be seen from FIGURES 3 and 4, at points 38-38 and on one side at point 40 so as to enable the rod to drop into retaining notches 22 and 26.

When in the in-use or assembled position, as shown in FIGURE 1, the rod which comprises supporting member 14 is locked in position through the cooperation of notches 22 and 26 respectively with grooves 38-38 and 40 in the rod which defines the supporting member. When the ladder is to be moved to anew location or put away for storage, support member 14 is raised slightly to disengage the grooved rod from the locking notches. The locked positions for the support member and bracket are shown in FIGURES l, 2, 3 and 4; FIGURE 3 depicting the locking action at the top of the apparatus and FIG- lURE 4 depicting the locking action at the bottom of the apparatus. After being released from the locking notches, support member 14 is turned toward the Ifront of the ladder thus assuming the position shown in part in FIG- URE 5. Comparison between FIGURES 2 and 5 shows the locked and unlocked positions of the supporting member relative to the bracket member. Once unlocked and rotated 9() degrees, support member 14 is moved upwardly, the rod sliding in the channel defined by members 16 and 20 of bracket means 12. FIGURES 6 and 7 depict an intermediate position in the removal of the support member from the bracket. When the bottom of the support member clears the top of the bracket, the support member is released from the bracket and may be stored separately, the bracket remaining permanently affixed to the side rails of the ladder.

When it is desired to again install the `safety device of the present invention on a ladder, the ladder is placed in the desired position and the support member 14 is merely dropped into the channel defined by the retaining member 20. vllVhen member 14 contacts and is thus stopped by region 21, it is rotated and allowed to lock itself into position. This `simple but sure action provides a steady support for the ladder, provides a much needed ease of assembly of the device and permits the protruding parts of the device to be removed `from the ladder when not in use.

Referring now to FIGURE 9, a second embodiment of the present invention is shown. The embodiment of FIGURE 9 differs from the embodiment of FIGURES l-S in two respects. Firstly, the bracket means of the embodiment of FIGURE 9 has been made in t'wo sections which are individually bolted to the side rail of the ladder. The making of the bracket in two pieces results in a safety device of lower cost and lighter weight as compared to the embodiment of FIGURES 1 8. The low cost results, in part, from the ability to form the ladder mounted brackets `as stam-pings. As shown in FIGURE 9, the two portions of the bracket means are indicated at 50 and l52. As in the embodiment in FIGURES l-S, the upper and lower locking notches 22 and 26 are respectively included on bracket portions 50 and 52 of the embodiment of FIGURE 9.

The embodiment of FIGURE 9 also differs from that of the previously described embodiment in that threaded rod 36 has been replaced by an eye-bolt 54 which is connected to base plate 34 by means of a lhasp or U-bolt 56. The eye-bolt-U-bolt arrangement permits the rotation of foot 34 such that its lower surface will be parallel to and in contact with the surface from which the ladder extends. As shown in FIGURE l, the edge of foot 34 will bite into the surface rather than resting fiat thereon as in the embodiment in FIGURE 9. To provide for a more secure locking of the plate 34 to the surface upon which it rests, the plate will typically be formed with a pattern of holes therein; small holes such as holes 58--58 being intended to accept nails which will be driven into the surface upon which the plate rests while the larger diameter holes 60-60 are intended to laccept pegs which will be used when the ladder is on a relatively soft surface such as the earth.

While preferred embodiments have been shown and described, various modifications and substitutions may be made thereto without departing lfrom the spirit and scope of this invention. Also, while the two disclosed embodiments have been shown as comprising single support members, it is to be understood that in practice there would usually be a left hand and right hand safety device affixed to the oppositely disposed side rails of the ladder. Accordingly, it is to be understood that the present invention has been described by way of illustration and not limitation.

What is claimed is: 1. A safety device for ladders comprising: ibase plate means adapted to be permanently affixed t a ladder side rail;

retainer means connected to said base plate means, said retainer means comprising at least a first channer defining member, said first member being arcuate in cross-section, one `side of said first member being attacted to said base plate means to define a longitudinally extending channel for receiving a removable support member, said channel extending in a direction parallel to the side rail; and

a removable support member, said support member including at least a first portion for installation in said channel and a second portion extending outwardly from said rst portion, said second portion engaging a medium upon which the ladder rests when in use.

2. The apparatus of claim 1 wherein at least part of said first channel defining member circumscribes an are of greater than but less than 180 thereby forming an opening between said base plate means and said first member, said opening communicating with said channel.

3. The apparatus of claim 2 wherein said first channel defining member further comprises:

locking means for engaging said support member, said locking means including at least a first longitudinally extending notch in said rst channel defining member, said first notch communicating with the top of said first member.

4. The apparatus of claim 3 wherein said outwardly extending second portion of said support member comprises:

a rst element which extends outwardly from a point adjacent the lower end of said irst portion; and

medium contacting to said Itirst element adjacent the end thereof which is disposed away from said iirst portion.

5. The apparatus of claim 4 wherein said support member further comprises:

a second element which extends between the upper end of said first portion and a point adjacent the end of said iirst element which is disposed away from said kiirst portion, said support memer thus bein-g closed on itself; and

at least a rst groove in said second element, the reduced thickness of said second element in the vicinity of said rst groove being commensurate with the width of said first notch in rst channel deiining member whereby said first notch and groove cooperated to lock said support member in a fixed position.

6. The apparatus of claim 5 wherein said support member further comprises:

a second groove, said second groove being formed in said rst element and being of sufficient depth and width to enable said support member to be removed from said channel by sliding said support member upwardly with the open end of said first channel deining means engaged in said second groove.

7. The apparatus of claim 6 wherein said foot means comprises:

a medium contacting plate, the distance between said plate and said iirst element being adjustable.

References Cited UNITED STATES PATENTS 1,890,029 12/1932 Delfs 182-172 2,324,414 7/1943 Morris 182-108 2,948,363 8/1960 Hopfeld 182-17 3,012,628 12/1961 Zumbaunl 182-172 REINALDO P. MACHADO, Primary Examiner.

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