US3750844A

US3750844A - Ladder assembly

Info

Publication number: US3750844A
Application number: US00287029A
Authority: US
Inventors: A Pandjiris; C Cooper
Original assignee: PANDJIRIS WELDMENT Co
Current assignee: PANDJIRIS WELDMENT COMPANY; PANDJIRIS WELDMENT Co
Priority date: 1972-09-07
Filing date: 1972-09-07
Publication date: 1973-08-07
Anticipated expiration: 1990-08-07
Also published as: CA967925A

Abstract

A ladder assembly in which the rungs are selectively and detachably retained in transversely aligned pairs of socket means carried by laterally spaced side posts, and a platform unit is mounted on the side posts at selectively predetermined elevations. The platform unit includes two pair of detents selectively and detachably seating in two pair of longitudinally spaced socket means, after removal of their associated rungs, to provide a force couple supporting the platform unit on the side posts. Rungs, otherwise located in socket means above the detents, are selectively removed for unobstructed access to the platform unit. Preferably, the socket means are top-open, substantially U-shaped stirrups mounted on the inside of the side posts, and the platform unit is located between the side posts, the platform detents extending laterally outward for selective insertion into the top-open stirrups. The stand member of the platform unit extends forwardly from a line interconnecting the first and second pairs of detents, and extends forwardly of the side posts when the detents are located in the stirrups. The stirrups have one leg longer than the other to facilitate location and insertion of the rungs and platform detents. A third pair of detents are provided in laterally spaced relation to one of the other pairs, the third pair of detents being selectively and detachably seated in the stirrups to effect a change in the inclination of the platform stand member. Welding equipment including a wire feeder, with its attendant torch and feeder conduit, is mounted to the ladder for elevation above the floor and at a height for location of the torch at a working level determined by the highest position of the platform unit. The method of adjusting a platform unit on a ladder which includes the steps of removing the rungs from the socket means at which the platform unit is to be located, raising the platform unit and seating the detents in the vacated socket means to locate the stand member between the side posts, and removing other rungs from their associated socket means above those socket means in which the platform detents are seated, to provide unobstructed access to the stand member of the platform unit.

Description

United States Patent 1 Pandjiris et al.

[ Aug. 7, 1973 i 1 LADDER ASSEMBLY [75] Inventors: Anthony K. Pandjlrls, St. Louis; Cleveland N. Cooper, Kirkwood, both of Mo.

[73] Assignee: The Psndjlris Weldment Co., St.

Louis, Mo.

[22] Filed: Sept. 7, 1972 [21] Appl. No.2 287,029

Primary Examiner-Reinaldo P. Machado Attorney-Cohn, Powell & Hind [57] ABSTRACT A ladder assembly in which the rungs are selectively and detachably retained in transversely aligned pairs of socket means carried by laterally spaced side posts, and a platform unit is mounted on the side posts at selectively predetermined elevations. The platform unit includes two pair of detents selectively and detachably seating in two pair of longitudinally spaced socket means, after removal of their associated rungs, to provide a force couple supporting the platform unit on the side posts. Rungs, otherwise located in socket means above the detents, are selectively removed for unobstructed access to the platform unit. Preferably, the socket means are top-open, substantially U-shaped stirrups mounted on the inside of the side posts, and the platform unit is located between the side posts, the platform detents extending laterally outward for selective insertion into the top-open stirrups. The stand member of the platform unit extends forwardly from a line interconnecting the first and second pairs of detents, and extends forwardly of the side posts when the detents are located in the stirrups. The stirrups have one leg longer than the other to facilitate location and insertion of the rungs and platform detents. A third pair of detents are provided in laterally spaced relation to one of the other pairs, the third pair of detents being selectively and detachably seated in the stirrups to effect a change in the inclination of the platform stand member. Welding equipment including a wire feeder, with its attendant torch and feeder conduit, is mounted to the ladder for elevation above the floor and at a height for location of the torch at a working level determined by the highest position of the platform unit.

The method of adjusting a platform unit on a ladder which includes the steps of removing the rungs from the socket means at which the platform unit is to be located, raising the platform unit and seating the detents in the vacated socket means to locate the stand member between the side posts, and removing other rungs from their associated socket means above those socket means in which the platform detents are seated, to provide unobstructed access to the stand member 0 the platform unit.

13 Claims, 7 Drawing Figures PAIENIEBM B 3.750.844 saw a or 2 FIG. 7

FIG. 5

b j Hm .HAU

HHLU

J FIG. 4

1 LADDER ASSEMBLY BACKGROUND OF THE INVENTION This invention relates generally to improvements in a ladder assembly, and more particularly to a ladder assembly having a selectively and detachably mounted platform unit on which the user can conveniently stand at a predetermined selected elevation.

In the heretofore conventional ladder assemblies, there was available a step or stand having attached sockets adapted .to fit over and receive existing ladder rungs. Because the rungs in such ladder were intended to remain fixed, access to such stand was obstructed by theexisting rungs and climbingthe ladder to such stand was difficult and at times hazardous.

SUMMARY OF THE INVENTION The present invention includes a ladder assembly in which top-open stirrups are provided for holding the ladder rungs, yet permitting removal of such rungs when it is desired to mount a platform unit in the stirrups. This assembly enables the removal of obstacles that would otherwise hinder easy access to the platform unit and eliminates any potentially hazardous condition.

The ladder assembly includes socket means carried by side posts in longitudinally spaced relation, and a plurality of rungs, each of which is selectively and detachably retained in a transversely aligned pair of socket means. A platform unit supported on the side posts, includes a stand member carried by and extending between a pair of laterally spaced side frame members, and two pair of longitudinally spaced detents which are selectively and detachably seated in compatible pairs of socket means after removal of the associated rungs, the connection of the detents and socket means supporting the platform unit. Rungs otherwise located in socket means above the detents, are selectively removable for unobstructed access to the platform .unit.

The socket means are preferably, substantially U- shaped stirrups which are top-open. One leg of the stirrup is longer than the other to facilitate location and insertion of the rungs and platform detents.

The platform unit is located between the side posts of the ladder, and the platform detents extend laterally outward for selective insertion into the top-open stirrups.

The side frame members of the platform unit include a pair of laterally spaced, substantially longitudinally parallel side stringers, and the stand member is located between the stringers. A bracket plate is attached to each stringer above the stand. A first pair of detents are carried by the side stringers and a second pair of detents are carried by the bracket plates.

A third pair of detents are carried by the bracket plates in laterally spaced relation to the second pair of detents, the third pair of detents being selectively and detachably seated in the stirrups instead of the second pair of detents to effect a change in the inclination of the platform unit.

Welding equipment including a wire feeder, with its attendant torch and feeder conduit, is mounted for elevation above the floor and at a height for location of the torch at a working level determined by the highest position of the platform unit.

The method of adjusting the platform unit on the ladder consists of the steps of removing the rungs from the socket means at which the platform unit is to be located, raising the platform unit and seating the detents in the vacated socket means to locate the stand between the side posts, and removing other rings from their associated socket means above those socket means in which the platform detents are seated, to provide unobstructed access to the stand member of the platform unit. Other rungs are maintained in their associated socket means below those socket means in which the platform detents are seated, to provide steps up to the stand member of the platform unit.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevational view of the ladder assembly showing its usage by a welder;

FIG. 2 is a rear elevational view of the platform unit;

FIG. 3 is a side elevational view of the platform unit shown in FIG. 2;

FIG. 4 is a rear elevational view of the ladder assembly without the base;

FIG. 5 is a cross sectional view as seen along line 5-5 of FIG. 4;

FIG. 6 is a fragmentary, top plan view of the structure shown in FIG. 5, and

FIG. 7 is an enlarged, fragmentary side elevational view of a stirrup with its associated rung in cross section.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now by characters of reference to the drawings and first to FIG. 1, it will be understood that the assembly includes a ladder generally indicated by 10 on which a platform unit referred to by 11 is selectively and detachably mounted in a predetermined height. In the preferred embodiment, the ladder assembly is illustrated as being used by a welder 12. The platform unit 11 is shown in broken lines to illustrate another predetermined, selected height position.

The ladder 10 includes a pair of laterally spaced, substantially parallel side posts 13. A cross brace 14 of box section, extends between and rigidly interconnects the lower ends of the side posts 13. Extending between and rigidly interconnecting the upper ends of the side posts 13 is a substantially U-shaped cross brace 15. This upper brace 15 includes forwardly extending arms 16, each having one end attached to the side posts 13 and the opposite end attached to a cross brace 17. The U- shaped brace 15 provides a passage for the person climbing the ladder 10.

The lower ends of the side posts 13 are attached to a base 18. The base 18 includes rollers 19 that can support the assembly on a subjacent surface such as a floor or a track. Diagonal braces 20 extend between and interconnect the base 18 with the side posts 13, the upper ends of the braces 20 being attached to the tabs 21 fixed to the side posts 13. Preferably, the ladder I0 is held in a slightly inclined position relative to the vertical.

Secured by welds 29 (FIG. 7) to the inside of each of the side posts 13, are a plurality of longitudinally spaced, substantially U-shaped stirrups 22, the stirrups 22 constituting top-open socket means. For reasons which will later appear, one leg 23 is longer than the other leg 24, the stirrups 22 being disposed so that the short leg 24 is located toward the front of the ladder. The stirrups 22 of one side post 13 are substantially transversely aligned with the stirrups of the other side post so as to selectively receive and seat a plurality of rungs in longitudinally spaced, horizontal positions. It will be understood that each rung 25 can be quickly and easily located over its associated pair of stirrups 22 and inserted into place. Similarly, each rung 25 can be readily and selectively removed. The longer stirrup leg 23 facilitates the location of the rungs.

The construction of the platform unit 11 is perhaps best illustrated in FIGS. 2 and 3. The platform unit 11 includes a pair of laterally spaced side frame members, each of which consists of an inclined side stringer 26 and a bracket plate 27 secured to the associated stringer 26 intermediate its ends. The side stringers 26 are arranged in laterally spaced, substantially longitudinally parallel relationship.

Extending between and rigidly interconnecting the lower ends of the side stringers 26, is a cross bar 30. Another cross bar 31 extends between and rigidly interconnects the upper ends of the side stringers 26. A stand member 32 consists of a curved metal plate which is secured at each side by a strip 33 to the associated bracket plate 27. A pair of substantially rectangular angle frames 34 are secured to the underside of the stand member 22 for reinforcement.

The outermost ends of the cross bar extend laterally outward from the side stringers 26 to provide a pair of laterally extending detents 35. A second pair of de tents 36 are secured to and extend laterally from the bracket plates 27 in vertically spaced position relative to the first pair of detents 35. When the platform unit 11 is secured to the ladder 10, the pairs of

detents

35 and 36 seat selectively and detachably in transversely aligned pairs of stirrups 22, after removal of the associated rungs 25 from such stirrups. The connection of the

detents

35 and 36 in the stirrups 22 support the platform unit 11 on the side posts 13.

A third pair of detents 37 are carried by the bracket plates 27 in laterally spaced relation to the detents 36. These detents 37 can be selectively and detachably seated in the stirrups 22 instead of the detents 36 to effect a change in the inclination of the platform unit. The stand member 22 extends forwardly from a line interconnecting the vertically spaced pairs of

detents

35 and 36 or of

detents

35 and 37, and extends forwardly of the side posts 13 when the detents are located in the stirrups 22.

The upper cross bar 31 constitutes a rest to support the user's body. Another cross bar 40 extends between and interconnects the bracket plates 27, and provides a rest to support the user's legs.

Secured to one of the side posts 13 by angle arm 41 and diagonal brace 42, is a shelf 43 adapted to support a wire feeder 44 with its attendant torch 45 and feeder conduit 46. This welding equipment is mounted to the ladder for elevation above the floor and at a height for location of the torch 45 at a working level determined by the highest position of the platform unit 11 on the ladder l0.

Of course, the ladder 10 can be utilized in its usual manner as a ladder without the platform unit 11. The rungs 25 will be located in their associated stirrups 22. The user will mount and dismount from the ladder in the usual way.

However, the platform unit 11 can be selectively and advantageously mounted to the ladder 10 at a predetermined elevation. To mount the platform unit 11, a pair of adjacent rungs 25 are removed from the stirrups at the location where the platform unit 11 is to be placed. The platform unit is raised and the

detents

35 and 36 are located in the vacated stirrups 22 to locate the platform unit including the stand member 32 between the side posts 13. Other rungs 25, above the stirrups 22 in which the

detents

35 and 36 are located, are removed from their associated stirrups 22 to provide unobstructed access to the stand member 32 of the platform unit 11. The rungs 25 below the stirrups 22 in which the

detents

35 and 36 are located, are maintained in their associated stirrups 22 to provide convenient steps up to the stand member 32 of the platform unit 1 1. If it is desired to change the inclination of the stand 32, the detents 37 can be located in the associated stirrups instead of the detents 36.

It will be understood, that the platform unit 11 can be located at any predetermined selected height along the length of the ladder 10. In FIG. 1, the platform unit 11 is shown in its uppermost position in full lines, and in its lowermost position in broken lines. It can be also conveniently located at any position therebetween.

The ladder assembly is most conveniently used for welding purposes as is illustrated in FIG. 1. The welder can mount the ladder l0 and stand on the platform unit 11. Because the welding equipment is attached to the ladder and held in an elevated position off of the ground, the welder can use the torch 45 with its fixed length of feeder conduit at any predetermined elevation of the platform unit 11.

We claim as our invention:

1. In a ladder assembly:

a. a pair of laterally spaced, substantially longitudinally parallel side posts,

b. means rigidly interconnecting the side posts,

c. socket means carried by the side posts in longitudinally spaced relation, the socket means of one post being substantially transversely aligned with the socket means of the other post,

d. a plurality of rungs, each rung being selectively and detachably retained in a transversely aligned pair of socket means,

e. a platform unit including:

1. a pair of laterally spaced side frame members,

2. a stand member carried by and extending between the frame members,

3. a first pair of detents selectively and detachably seating in a transversely aligned pair of socket means after removal of its associated rung, and

4. a second pair of detents spaced longitudinally from the said first pair, selectively and detachably seating in another transversely aligned pair of socket means longitudinally spaced along the side posts from the socket means occupied by the first pair of detents, after removal of its associated rung, the connection of the detents and socket means providing a force couple supporting the platform unit on the side posts, and

f. rungs, otherwise located in socket means above the detents, selectively removable for unobstructed access to the platform unit.

2. A ladder assembly as defined in claim 1, in which:

g. the stand extends forwardly from a line interconnecting the first and second pair of detents, and extends forwardly of the side posts when the detents are located in the socket means.

3. A ladder assembly as defined in claim 1, in which:

g. the socket means are top-open for insertion or removal of the rungs and platform detents.

4. A ladder assembly as defined in claim 3, in which:

h. the platform unit is located between the side posts,

and

i. the platform detents extend laterally outward for selective insertion into the top-open socket means.

5. A ladder assembly as defined in claim 4, in which:

j. the socket means are substantially U-shaped stirrups.

6. A ladder assembly as defined in claim 1, in which:

g. the stand extends forwardly from a line interconnecting the first and second pair of detents, and extends forwardly of the side posts when the detents are located in the socket means,

h. the socket means are top-open, substantially U- shaped stirrups mounted on the inside of the side posts,

the platform unit is located between side posts with its side frame members between the stirrups, and j. the platform detents extend laterally outward for selective insertion into the top-open stirrups.

7. A ladder assembly as defined in claim 1, in which:

g. the substantially U-shaped stirrups have one leg longer than the other to facilitate location and insertion of the rungs and platform detents.

8. A ladder assembly as defined in claim 6, in which:

k. the side frame members of the platform unit include:

l. a pair of laterally spaced, substantially longitudinally parallel side stringers,

2. the stand member being located between the stringers, and

3. a bracket plate attached to each stringer above the stand member,

. the first pair of detents are carried by the side stringers, and the second pair of detents are carried by the bracket plates.

9. A ladder assembly as defined in claim 8, in which:

m. a third pair of detents are carried by the bracket above the stand member at the front side of the platform unit to support the users legs, and

0. another rest bar extends between the side stringers above the first said rest bar at. the front side of the platform unit to support the user's body.

11. A ladder assembly as defined in claim 1, in which:

g. welding equipment including a wire feeder, with its attendant torch and feeder conduit, is mounted to the ladder for elevation above the floor and at a height for location of the torch at a working level determined by the highest position of the platform unit.

12. The method of adjusting a platform unit on a lad der in which the ladder includes side posts, socket means carried .by these side posts, and rungs selectively and detachably seated in the socket means, and the platform unit includes a stand member and two cooperating pair of detents that are longitudinally spaced, comprising the steps of:

a. removing the rungs from the socket means at which the platform unit is to be located,

b. raising the platform unit and seating the detents in the vacated socket means to locate the stand member between the side posts, and

c. removing other rungs from their associated socket means above those socket means in which the platform detents are seated to provide unobstructed access to this stand member of the platform unit.

13. The method of adjusting a platform unit on a ladder as defined in claim 12, including the further step of:

d. maintaining the rungs in their associated socket means below those socket means in which the platform detents are seated, to provide convenient steps up to the stand member of the elevated platform unit.

Claims

1. In a ladder assembly: a. a pair of laterally spaced, substantially longitudinally parallel side posts, b. means rigidly interconnecting the side posts, c. socket means carried by the side posts in longitudinally spaced relation, the socket means of one post being substantially transversely aligned with the socket means of the other post, d. a plurality of rungs, each rung being selectively and detachably retained in a transversely aligned pair of socket means, e. a platform unit including: 1. a pair of laterally spaced side frame members, 2. a stand member carried by and extending between the frame members, 3. a first pair of detents selectively and detachably seating in a transversely aligned pair of socket means after removal of its associated rung, and 4. a second pair of detents spaced longitudinally from the said first pair, selectively and detachably seating in another transversely aligned pair of socket means longitudinally spaced along the side posts from the socket means occupied by the first pair of detents, after removal of its associated rung, the connection of the detents and socket means providing a force couple supporting the platform unit on the side posts, and f. rungs, otherwise located in socket means above the detents, selectively removable for unobstructed access to the platform unit.

2. a stand member carried by and extending between the frame members,

2. A ladder assembly as defined in claim 1, in which: g. the stand extends forwardly from a line interconnecting the first and second pair of detents, and extends forwardly of the side posts when the detents are located in the sockEt means.

2. the stand member being located between the stringers, and

3. a bracket plate attached to each stringer above the stand member, l. the first pair of detents are carried by the side stringers, and the second pair of detents are carried by the bracket plates.

3. A ladder assembly as defined in claim 1, in which: g. the socket means are top-open for insertion or removal of the rungs and platform detents.

4. a second pair of detents spaced longitudinally from the said first pair, selectively and detachably seating in another transversely aligned pair of socket means longitudinally spaced along the side posts from the socket means occupied by the first pair of detents, after removal of its associated rung, the connection of the detents and socket means providing a force couple supporting the platform unit on the side posts, and f. rungs, otherwise located in socket means above the detents, selectively removable for unobstructed access to the platform unit.

4. A ladder assembly as defined in claim 3, in which: h. the platform unit is located between the side posts, and i. the platform detents extend laterally outward for selective insertion into the top-open socket means.

5. A ladder assembly as defined in claim 4, in which: j. the socket means are substantially U-shaped stirrups.

6. A ladder assembly as defined in claim 1, in which: g. the stand extends forwardly from a line interconnecting the first and second pair of detents, and extends forwardly of the side posts when the detents are located in the socket means, h. the socket means are top-open, substantially U-shaped stirrups mounted on the inside of the side posts, i. the platform unit is located between side posts with its side frame members between the stirrups, and j. the platform detents extend laterally outward for selective insertion into the top-open stirrups.

7. A ladder assembly as defined in claim 1, in which: g. the substantially U-shaped stirrups have one leg longer than the other to facilitate location and insertion of the rungs and platform detents.

8. A ladder assembly as defined in claim 6, in which: k. the side frame members of the platform unit include:

9. A ladder assembly as defined in claim 8, in which: m. a third pair of detents are carried by the bracket plates in laterally spaced relation to the second pair of detents, the third pair of detents being selectively and detachably seated in the stirrups instead of the second pair of detents to effect a change in the inclination of the platform unit.

10. A ladder assembly as defined in claim 9, in which: n. a rest bar extends between the bracket plates and above the stand member at the front side of the platform unit to support the user''s legs, and o. another rest bar extends between the side stringers above the first said rest bar at the front side of the platform unit to support the user''s body.

11. A ladder assembly as defined in claim 1, in which: g. welding equipment including a wire feeder, with its attendant torch and feeder conduit, is mounted to the ladder for elevation above the floor and at a height for location of the torch at a working level determined by the highest position of the platform unit.

12. The method of adjusting a platform unit on a ladder in which the ladder includes side posts, socket means carried by these side posts, and rungs selectively and detachably seated in the socket means, and the platform unit includes a stand member and two cooperating pair of detents that are longitudinally spaced, comprising the steps of: a. removing the rungs from the socket means at which the platform unit is to be located, b. raising the platform unit and seating the detents in the vacated socket means to locate the stand member between the side posts, and c. removing other rungs from their associated socket means above those socket means in which the platform detents are seated to provide unobstructed access to this stand member of the platform unit.

13. The method of adjusting a platform unit on a ladder as defined in claim 12, including the further step of: d. maintaining the rungs in their associated socket means below those socket means in which the platform detents are seated, to provide convenient steps up to the stand member of the elevated platform unit.