US3891054A

US3891054A - Ladder stabilizers

Info

Publication number: US3891054A
Application number: US486811A
Authority: US
Inventors: Clayton E Larson
Original assignee: White Metal Rolling and Stamping Corp
Current assignee: White Metal Rolling and Stamping Corp
Priority date: 1974-07-09
Filing date: 1974-07-09
Publication date: 1975-06-24
Anticipated expiration: 1992-06-24

Abstract

Ladder stabilizers are formed of channel members fixed at each side of a ladder below the bottom step or rung. An extendible member telescopes in each channel member outwardly to the floor and is held in such extended position by a lock pin to effectively double the supportive flare of the ladder. Such stabilizers may be supplied as an integral part of a ladder or sold separately as an accessory.

Description

United States Patent Larson June 24, 1975 [541 LADDER STABILIZERS FOREIGN PATENTS OR APPLICATIONS lnventorl Clayton Larsofl, Brooklyn, 519,095 12/1955 Canada 182/201 [73] Assignee: White Metal Rolling & Stamping Corporation, Brooklyn, NY Primary Exammer-Re1naldo P. Machado Attorney, Agent, or Firml(emon, Palmer & [22] F1led: July 9, 1974 Estabrook 21 Appl. No.: 486,811

[57] ABSTRACT 52 us. 01. 182/107 Ladder Stabilizers are formed of channel members 51 Int. Cl. E06c 7/42 fixed at each Side of a ladder below bottom Step [58] Field 01 Search 182/107. 108, 201, 203, extendible member telescopes in each 182 /204 nel member outwardly to the floor and is held in such extended position by a lock pin to effectively double [56] References Cited the supportive flare 0f the ladder. Such stabilizers may UNITED STATES PATENTS be supplied as an integral part of a ladder or sold separatel as an accessor 2,936,849 5/1960 Larson 182/204 y y 3,363.960 1/1968 Reiss 308/316 7 Claims, 6 Drawing Figures 1 LADDER STABILIZERS BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to ladders and specifically, to stabilizers that increase the supportive flare of ladders to improve their safety by reducing the possibility of slippage or tipping.

2. Description of the Prior Art All ladders are subject to slipping or tipping. The possibility of tipping presents a special safety problem for stepladders because many users of stepladders attempt to reach to the side of the ladder beyond a point where the flare of the ladder feet will maintain a stable upright position. While stabilizing attachments for ladders are known, e.g., see US. Pat. Nos. 495,920; 1,283,212; 2,868,427; 3,059,723 and 3,618,703, such devices have not met with much success due to their complex and cumbersome structure and/or their ineffectiveness. Increased demand for improved ladder safety by users and government regulations creates a need for .ladder stabilizers that are easy to use, simple in construction and really do serve to mitigate slippage and tipping of ladders to which they are attached.

SUMMARY OF THE INVENTION Ladder stabilizers of the invention are simple in construction and inexpensive to manufacture. Furthermore, they do not present a handling or storage problem since they are designed to form a permanent part of a ladder and are capable of being moved into a retracted position so that they do not substantially increase the dimensions of the ladder.

The new ladder stabilizers comprise a channel member designed for attachment at each side of a ladder with one end fixed to the lowest step member of the ladder and with the other end fixed to a side rail of the ladder. The channel members angle downwardly with respect to the lowest step member and telescopically carry a bar or equivalent extendable member which moves between a retracted position where the lower end of the bar is adjacent the corresponding side rail and an extended position where the lower end of the bar engages the floor or other area which constitutes the plane defined by the feet of the ladder siderails. A hole extends through each channel member adjacent the corresponding side rail with the axis of the hole being perpendicular to the face of the channel member. Lock means are carried by each channel member comprising a pin slidably extending through the channel hole and spring means which urges the pin into the channel hole. A pair of holes extend through each of the telescoping bars, one of the holes of the bar being located so that when the spring biased pin extends therethrough, the bar is held in the retracted position while the other hole is located in the bar so that when such pin extends through that hole, the bar is held in the extended position. With both extendable bars locked by their respective pins in the extended position, the supportive flare of the ladder is approximately doubled so its stability is substantially improved.

BRIEF DESCRIPTION OF THE DRAWINGS A more complete understanding of the new ladder stabilizers of the invention and their manner of use may be held by reference to the accompanying drawings in which:

FIG. 1 is a perspective view of a stepladder comprising ladder stabilizers of the invention.

FIG. 2 is a fragmentary side view (partially sectioned) of the lower end of the front step section of the ladder of FIG. 1.

FIG. 3 is a fragmentary rear view of the ladder portion shown in FIG. 2 with the ladder stabilizer in extended position.

FIG. 4 is a fragmentary rear view corresponding to FIG. 3, but with the ladder stabilizer in retracted position.

FIG. 5 is a sectional view taken along the line 5-5 of FIG. 4.

FIG. 6 is a sectional view taken along the line 6-6 of FIG. 4.

DESCRIPTION OF PREFERRED EMBODIMENT Although the ladder stabilizers of the invention may be used with any form of ladder including straight ladders, extension ladders and the like, they are particularly useful in connection with stepladders and they will be described and illustrated in connection with this preferred embodiment.

The stepladder 2 comprises the front step section 4, the rear prop section 6, spreader means 8 and a foldable bucket rack 10. The parts of the ladder, aside from fastenings, are preferably made of extruded metal, e.g., aluminum. Fastenings are preferably aluminum rivets but rivets of any other metal, nuts and bolts or equivalent fastenings may be used to assemble the various structural members of the ladder.

The front step section 4 comprises a pair of side rails 12 of channel form and a plurality of step members 14. In the illustrated embodiment, step members are flat steps formed of extruded metal channel but they could take other forms, e.g., flat plates, rungs or the like. Braces 16 provide required rigidity and resistance against sway when the ladder is loaded by the weight of the user. The non-slip feet 17 of the side rails 12 comprise rubber pads 18 fixed to metal end members 19.

The ladder stabilizers 20 comprise a pair of channel members 22 one of which is fixed at one side of the ladder and the other at the opposite side. Each channel member is fixed at its top end 24 by a rivet 26 to the rear web 28 of the lowest step 14 of the ladder. The bottom end 30 of the channel member 22 is fixed by rivet 32 to the rear web 34 of the side rail 12 with a spacing washer 35 inserted between them. Where the new stabilizers are obtained separately from the ladder as an accessory, machine screws or nuts and bolts may be used as fasteners in place of the

rivets

26 and 32.

The channel members 20 angle downwardly with respect to the step member 14 and each telescopically carries an extendable member 36 which is preferably in the form of a bar having two plain surfaces 38 and two concave surfaces 40 (see FIG. 5). The concave surfaces provide clearance for the heads of

rivets

26 and 32 so the bars 36 may slide freely in the channel members 20.

A hole 42 extends through each channel member adjacent the corresponding side rail 12, the axis of the hole being perpendicular to the face 44 of the channel member 22.

Lock means 46 is fixed by rivets 48 to the channel member 20 so that a pin 50 can extend through the channel hole 42. The pin 50 is journaled at its upper end 52 in the U-shaped guide member 54.and a coil spring 56 is compressed beneath the guide member54 and a cotter pin 58 extending through the lock pin 50. Accordingly, the lock pin is biased to extend through the channel hole 42. A lift washer 60 surrounds the lock pin 50 at the top end 52 beneath the lock pin head 62.

The bar 36 has a pair of

holes

64 and 66 extending therethrough of such size as to permit the lower end 68 of the lock pin 50 to extend therethrough. The lower end 70 of the bar 36 consists of a pad 72 molded from rubber or plastic. The bar hole 64 is located on the bar 36 so that when the bar is in the retracted position (see FIG. 4) the end 68 of the pin 50 extends therethrough. The bar hole 66 is located so that the pin 50 extends through it when the bar is in the extended position (see FIG. 3). In the extended position, the lower end 70 of the bar engages the floor or other plane 74 defined by the feet 17 of the ladder side rails.

The ladder stabilizers of the invention serve a useful function in addition to helping protect a ladder from slipping or tipping. Thus, each channel member 22 replaces a brace 16 which would be needed to provide adequate rigidity to the base of the front section of the ladder. This makes the added labor for including the stabilizers in a finished ladder, such as shown in FIG. 1, minimal.

In the use of a step ladder provided with stabilizers in accordance with the invention, the extendable members 36 of each stabilizer will be locked in the extended position as shown in FIGS. 1 and 3. On completion of use of the ladder, each stabilizer is moved into the retracted position as shown in FIG. 4. This is accomplished bygrasping the lift washer 60 and pulling it away from the guide member 54 thereby lifting the pin 50 out of the hole 64. The bar 36 may then be telescoped into the channel member 22, meanwhile releasing the lift washer 60 so that upon reaching the retracted position, the pin 50 will snap through the bar hole 66. In thisposition, the ladder can be easily transported or stored and the bar 36 is protected against accidental bending or other damage.

I claim:

1. In combination with a ladder having a pair of side rails bearing step members, a stabilizer comprising:

a pair of channel members each fixed at its top end to the lowest step member of the ladder and at its bottom end to one of the side rails of the ladder between the point of juncture of said lowest step member with said side rail and the foot of said side rail, the channel members being angled downward with respect to said lowest step member,

a bar telescopically carried by each channel member to move between a retracted position where the lower end of the bar is adjacent the corresponding side rail and an extended position where the lower end of the bar engages the plane defined by the feet of the ladder side rails,

a hole extending through each channel member adjacent the corresponding side rail, the axis of the hole being perpendicular to the face of the channel member,

lock means carried by each channel member com-' prising a pin slidably extending through said channel hole and spring means urging said pin into said channel hole, and

a pair of holes extending through each of said bars through which said pin may extend, one of said bar holes being located in the bar so that when the pin extends therethrough the bar is held in said retracted position and the other bar hole being located in the barso that when the pin extends therethrough, the bar is held in said extended position.

2. In combination with a stepladder having a front step section including a pair of side rails bearing steps, a stabilizer comprising:

a pair of channel members each fixed at its top end to the lowest step of the ladder and at its bottom end to one of the side rails of the ladder between the point of juncture of said lowest step member with said side rail and the foot of said side rail, the channel members being angled downward with respect to said lowest step,

lock means carried by each channel member comprising a pin slidably extending through said channel hole, a U-shaped guide member and a coil spring compressed beneath said guide member urging said pin into said channel hole, and

a pair of holes extending through each of said bars through which said pin may extend, one of said bar holes being located in the bar so that when the pin extends therethrough the bar is held in said retracted position and the other bar hole being located in the bar so that when the pin extends therethrough the bar is held in said extended position.

3. The ladder stabilizer of claim 1 wherein said bars have at least one concave surface.

4. The ladder stabilizer of claim 3 wherein said channel members are fixed to said lowest step member and side rails by rivets and the concavity depth of said concave surface is greater than the height of the rivet heads.

5. The stepladder of claim 2 wherein said lower end of said bar comprises a molded pad.

6. The stepladder of claim 5 wherein the feet of said side rails comprises non-slip pads.

7. The stepladder of claim 2 wherein said bars have two parallel flat surfaces and two concave surfaces and said bar holes extend through said concave surfaces.

Claims

1. In combination with a ladder having a pair of side rails bearing step members, a stabilizer comprising: a pair of channel members each fixed at its top end to the lowest step member of the ladder and at its bottom end to one of the side rails of the ladder between the point of juncture of said lowest step member with said side rail and the foot of said side rail, the channel members being angled downward with respect to said lowest step member, a bar telescopically carried by each channel member to move between a retracted position where the lower end of the bar is adjacent the corresponding side rail and an extended position where the lower end of the bar engages the plane defined by the feet of the ladder side rails, a hole extending through each channel member adjacent the corresponding side rail, the axis of the hole being perpendicular to the face of the channel member, lock means carried by each channel member comprising a pin slidably extending through said channel hole and spring means urging said pin into said channel hole, and a pair of holes extending through each of said bars through which said pin may extend, one of said bar holes being located in the bar so that when the pin extends therethrough the bar is held in said retracted position and the other bar hole being located in the bar so that when the pin extends therethrough, the bar is held in said extended position.

2. In combination with a stepladder having a front step section including a pair of side rails bearing steps, a stabilizer comprising: a pair of channel members each fixed at its top end to the lowest step of the ladder and at its bottom end to one of the side rails of the ladder between the point of juncture of said lowest step member with said side rail and the foot of said side rail, the channel members being angled downward with respect to said lowest step, a bar telescopically carried by each channel member to move between a retracted position where the lower end of the bar is adjacent the corresponding side rail and an extended position where the lower end of the bar engages the plane defined by the feet of the ladder side rails, a hole extending through each channel member adjacent the corresponding side rail, the axis of the hole being perpendicular to the face of the channel member, lock means carried by each channel member comprising a pin slidably extending through said channel hole, a U-shaped guide member and a coil spring compressed beneath said guide member urging said pin into said channel hole, and a pair of holes extending througH each of said bars through which said pin may extend, one of said bar holes being located in the bar so that when the pin extends therethrough the bar is held in said retracted position and the other bar hole being located in the bar so that when the pin extends therethrough the bar is held in said extended position.