US2542256A - Shiftable ladder support - Google Patents

Description

Feb. 20, 1951 F. MEHRINGER 2,542,256

SHIFTAB LE LADDER SUPPORT Filed March 22, 1948 IN V EN TOR.

Patented Feb. 20, 1951 UNiTED STATES FATENT OFFICE SHXFTABLE LADDER SUPPORT Frank Mehringer, Milwaukee, Wis.

Application March 22, 1948, Serial No. 16,377

4 Claims.

This invention relat? shiftable ladder supports.

Painters, window cleaners, maintenance men, and the like, find it necessary to make extensive use of ladders. When using the conventional non-ambulant type of ladder the workman is required to climb down from the ladder each time it becomes necessary to shift it to a new location. Upon arriving at the bottom of the ladder he must then move it to the changed position and then again ascend in order to continue working. This procedure is not only tiresome and timeconsuming, but is also dangerous. A misstep in ascending or descending a ladder can result in a very serious accident, and the greater the frequency of such ascent or descent, the greater the possibility of accidents occurring therefrom.

to improvements in It is therefore a general object of the inven-.

tion to provide a shiftable support for a ladder whereby a workman can move a ladder longitudinally of any wall against which it is supported, without having to descend from his position on the ladder.

A further object of the inventionis to provide a shiftable ladder support, the lower or carriage portion of which is provided with brake means which automatically locks the carriage against movement when it is not positively actuated by the workman.

A further object of the invention is to provide a shiftable ladder support of the class described which permits turning of the ladder to conform to irregularities, such as bays and the like, which form part of the wall against which the ladder is supported.

A further object of the invention is to provide a shiftable ladder support for use in conjunction with a conventional ladder which comprises a wheeled support for the base of the ladder, as well as a Wheeled support for the top or intermediate portions of the ladder.

A further object of the invention is to provide a shiftable ladder support which may be quickly attached to or disconnected from a conventional ladder.

A further object of the invention is to provide a shiftable ladder support which includesa wheeled support for an upper or intermediate portion of the ladder, which wheeled support is connectable to any selected pair 'of adjacent ladder rungs and is provided with extensible legs for supporting the ladder at a selected distance spaced away from the wall against which the ladder is positioned.

A further object of the invention is to provide a shiftable ladder support having a wheeled support for an upper or intermediate portion.

of the ladder, thewheels of which may be selectively turned to a position permitting travel laterallyalong a wall or to a position at right angles to the first-mentioned position wherein movement along the wall is prevented.

With the above and other objects in view, the invention consists of the improved shiftable ladder support, and all of its parts and combinations, as set forth in the claims, and all equivalents thereof.

In the drawing accompanying and forming a part of this application, wherein is illustrated one complete embodiment of the preferred form of the invention, and wherein the same reference characters represent the same parts in all of the views;

Fig. 1 is a fragmentary perspective view showing the wheeled support for the bottom of the ladder, the upper portions of the ladder being broken away;

Fig. 2 is a fragmentary perspective view on a. slightly larger scale showing the lower wheeled support or carriage with the turntable platform removed and with the front portions of the carriage broken away;

Fig. 3 is a front end perspective view of the carriage on a smaller scale, showing the invention attached to and supporting a ladder :adja-.

cent a wall, part of the ladder being broken away and shown in section to better show the upper support;

Fig. 4 is a top perspective view ofthe upper wheeled support; and

Fig. 5 is a diagrammatic side elevational view of the lower wheeled support or carriage show ing the operation of the brakes and brake levers.

Referring more particularly to Fig. 3 of the drawing, the numeral It) indicates a conventional ladder, to an intermediate portion of which is connected an upper wheeled support H. The ladder i0 is supported at itsv base on a lower wheeled support or carriage l2.

.In'ithe preferred.- form, the carriage 12 comprises a frame formed of a pair of substantially parallel angle members It. Projecting forwardly and upwardly from the forward ends of the members I3, as is clearly shown in Fig. 1, is a tubular M, having a substantially U-' is a U-shaped yoke E5, the arms of which projectv downwardly and are apertured adjacent the ends thereof, as at is (see Fig. 1). Mounted in the apertures 46 of the yoke 15 is a front axle I! which is locked against axial movement by a pair of diametrically extending cotter keys I8 projecting therethrough adjacent the inner surfaces of the arms of the yoke I5. A pair of wheels l9 are mount-.d for rotation on the outer ends of the axle l1.

Pivotally mounted on the axle. ll, preferably between the arms of the yoke l and the wheels l7, and extending forwardly therefrom, are the arms of a substantially V-shaped tongue member 20. Fixed to the forward end of the member 20 is a double sheave pulley 2|. Pivotally connected to the arms of the member 28, as' by the pins 22 (see Fig. 1), are a pair of downwardly and rearwardly extending brake arms 23. Connected to the lower ends of the brake arms]?- is a horizontal transverse brake member 24. The swinging movement of the arms 23 is limited by a transverse slot 25 in each of said arms, in which slot. pins 26 are adapted. to travel, the. latter: be.- ing fixedly connected to the arms of: the member 20.

' Spaced rearwardly of, the forward end of the: member: i l and connected transversely-to both of. the arms thereof, is a: strap member 21:. Rigidly connected to the strap member and extending forwardly and downwardly to pivotally connectwith the axle I'i, as at 28, is a: brace 29. Spaced above the strap 21 and supported thereon by a. connecting member 30, is a double sheave pulley 31. Connected to: the underside of the left hand arm of the member is and. adjacent the; forward.

end of the left hand frame member [.3 is a, guide-1oop32, the function of which will become apparent hereinafter...

The frame members l3 are formed with; corresponding apertures 33 adjacent the. rear ends thereof, and mounted" in said: apertures transversel'y of the. frame members i 3; isiarear'axle. 34;. Mounted for rotation on the outer-ends of. the rear'axle 34 is. a pair Of'WhEElSi 3.5;. The axle 34 is locked against rotation or axial movement by abolt which rigidly connects, itrto one. of the.

frame-members l3;

Pivotally connected to each of theframe=members l3 rearwardly of: the axle: 34 is a brake arm 3?. The arm 31 connected to the left hand. frame member: l3 extends upwardly beyond said frame member. as: shown. inEig- 2.. Connected.

to; the lower ends: of the brake arms 31 is a:- horizontally extending brake member; 38.. Mounted on'the' outer side of therleft hand frame member I3 forward of the axle 34- is; a single sheave pulley 39.

Positioned intermediate the length ofthe' frame i2 and preferably supported onand connected to the frame members this a transverse frame member 41ft. Superimposedon the member 40, and

fixed. thereto is a bearing plate 4!, preferably formed with a bearingrcollar: 42'. The plate ll, asxwell as the member All, are: apertured as at 43,.

Mounted upon the: forward; ends. of. the frame members. [3; are a pair of. spaced transversely extending: anglebracketstl i and 45* (see Fig. 2),. Rotatably supported between the angle brackets 6t! and are; preferably three; spacedrollers 4.6 whichextend substantially radially with respect: tothe: aperture 43 in the plate 4|.

Spaced: rearwardly from. the member 40... ap-

proximately the. samev distance therefrom. as: are

the. brackets Maud 4155 and mounted on the frame: members [3" are a. pair of. spaced: transverse angle brackets 41 and d8. Rotatably carried by the brackets 37 and 38 are preferably three spaced rollers 39 which also extmd substantially radially with respect to the aperture 33 in the plate 4!. The upper surfaces of the rollers 46 and 5% project above the brackets cc and 45 and above the brackets ll andild respectively.

' Supported on the rollers 46 and 49 is an elongated platform 59. Extending downwardly through the, central portion of the platform 5E and through the aperture 43 of the plate ti and member 40 is a pivot bolt 5i. The platform 50 is susceptible of turntable movement about the boltrfii, and the disposition of the rollers til and t9 provides for support of the ends of the platform 59 in any position thereof Within the limits of. its turning range. Experience has shown that a turning range of about 10 in either direction from the neutral longitudinal position of the platform 5%! shown in Fig. 1 is safe and is sufficient for most purp0s-s. Extending upwardly from each end of the platform 50 and from the central portion thereof are bearing plates 52. The plates 52 are formed with alined apertures 53. Arod. 54 is removably supported in the apertures! 53 of the plates 52 as shown in Fig. 1..

A conventional ladder It may be mounted on the platform 50 by forming corresponding apertures adjacent the lower end of each leg thereof and by placing the apertured portions of the ladder on the platform 5%] with the rod 54' extending through the apertures 53 of the plates 52 as well as through the apertures 55 of. the ladder H]. In this relationship, the lad.- der I0 is locked in position on the platform 59, as is evident from Fig. 1.

Preferably prior to the attachment of the ladder ill to the platform as of the carriage 32, the upper ladder support H is attached to a pair of adjacent rungs. 56 and 5 of the ladder ll]; Referring to Figs. 3 and- 4, the support it preferably includes. a generally U-shaped horizontallyextendingi member 58-, the ends of which are bent to form rung engaging members 59. The rung engaging members 59 are adapted to engage the rung 56, which is. the upper of the two rungs mentioned. Projecting angularly downwardly'from a central portion of the member 58 is a. bracket 60, the lower end of which is formed with a rung engaging member 5!. The member" 61 is provided with a. bolt 62 and Wingnut: 63 to lock the member 6! to the rung,

51' as shown. in Fig. 3, thereby locking the upper wheeled support H to the ladder ill in the manner: shown..

The member 58 is formed with a pair of spaced bosses 64 on the outer side of an intermediate portion thereof (see Fig; 4). The bosses 64 and'the member 58 are apertured, and threaded into said aperture are a ,pair' of elongated threadedarms 65, each of which is provided with a winged: lock nut 66. Mounted for rotation on: the. outer ends of the arms 65 are a pair o.f.;wheels 6'l;.. By reason of the threaded connection. between: the. arms: 65 and the bosses 64 the distance away from the member 58 at which; the; wheels: 61 are: supported may be readily-varied; In addition, the arms 65 with.

thewheels 6'! may be. selectively'turned so that the wheels 51 extendeither'in substantially the same plane- (as shown in Fig: 4) or in planes at right angles thereto (asshownin Fig. 3), and the: wingnuts'fifi may be-used to lock the arms 5.5 in. any desired positionv of longitudinal and rotative adjustment.

In use of the invention the apparatus as shown in Fig. 3 is positioned alongside one end of the wall which the workman wishes to traverse. The carriage I2 is spaced away from the wall and is preferably positioned substantially parallel thereto, as shown. Preferably beyond the end of the wall and remote from the carriage 12 a single sheave pulley B8 is suitably mounted, as for example, by being connected to a stake B9 driven into the ground. A relatively small rope or line 19 is then tied at one end to the upper end of the left hand rear brake lever 31 as shown in Fig. 2. The line 10 is then brought forwardly and threaded through the pulley 39, through the guide loop 32, through one sheave of the pulley 3|, through one sheave of the pulley 2|, and is then carried to the sheave 68. The line in is threaded through the sheave 68, is carried back through the second pulley of sheave 2|, through the second pulley of sheave 3|, and is then extended up the ladder ID to any rung which is convenient to the workman on the ladder. The line Ill is preferably secured to said rung as shown in Fig. 3.

With the apparatus in the relationship shown in Figs. 1 and 3, the ladder In is firmly supported by the carriage l2 and by the upper support H, and the workman can stand on the ladder anywhere he chooses to do his work. The carriage I2 is prevented from moving longitudinally by reason of the action of the brakes 2d and 38 against the wheels is and 35 respectively. Referring to the solid line showing in the schematic diagram of Fig. 5, it is apparent that the front brake 24 prevents forward movement of the carriage l2 and the rear brake38 prevents rearward movement. The wheels 61 of the upper support H are shown in Fig. 3 to extend in a vertical plane, and thereby lock the support I I and the upper portions of the ladder it) against lateral movement along the wall.

When the workman desires to move the ladder laterally along the wall in the direction toward the sheave 68, he may do so without descending from his position on the ladder. All he need do is loosen the wingnuts 66 on the arms 55, turn the arms 65 and the wheels 6'! so that the wheels extend in substantially'the same plane (as shown in Fig. 4), tighten the wingnuts 66 to lock the arms 65 against rotation, and then pull upwardly on the line 16. An upward pull on the upper end of the line 'H) will have two main effects. First, as shown by the dot and dash lines of Fig. 5, the tension causes a raising of the tongue member 20, which permits the brake arm 23 and the brake 24 to swing downward relative to the member 20 and away from the front wheels [8. Substantially simultaneously with the release of the front brake 2d, the tension on the line 18 causes an upward and rearward swinging movement of the rear brake levers 3'! and the rear brake-38. As is clearly shown in Fig. 5, this swinging movement brings the rear brake 33 out of contact with the rear wheels 35. Upon the release of the front and rear brakes, further tension in the line 20 will pull the carriage. E2 toward the sheave 68. As the carriage l2 moves, the wheels 61 roll along the wall and permit movement of the ladder 19 along with the carriage.

When the assembly has been moved a desired distance, release of the tension on the line 16 will immediately permit the tongue member 20 and the rear brake levers 3'! to swing downwardly and to thereby bring the brakes 24 and 38 into contact With the front and rear wheels respectively, locking the carriage 12 against longitudinal movement in either direction. The wingnuts 66 should then be loosened and the wheels 6'? turned to again extend in vertical planes as shown in Fig. 3, to lock the upper support i against lateral movement.

By reason of the longitudinal adj-ustability of the arms 65 relative to the frame 58, the ladder ill may be held by the upper support 5 l in a position spaced any desired distance away from the wall. For example, if it is desired to have the ladder positioned outwardly from the eaves of a house, an extension of the arms 65 will so permit. It will be noted, in this regard, that when using the invention it is never necessary to lean the ladder against eavestroug-hs or other easily damaged portions of a building. The support ll can be selectively attached to the ladder at a height where, in traversing the wall, it will not come in contact with windows, doors or the like, but instead will have a clear surface against which to travel throughout the length of the wall.

When the carriage travels toward the sheave 68 and the wheels 6'! of the upper support I! roll along the wall and come to a bay window, the wheels 51 will traverse the bay in the same manne as if it were a flat wall. liy reason of the turntable feature of the platform 53, the ladder and the platform will turn relative to the carriage 52 in order to conform to the irregularity in the wail caused by the bay. The carriage, however, will continue to travel in a straight line toward the sheave 88, while the platform 5% and the ladder it are turning in their travel forward. as above described.

To disassemble the improved ladder support it is only necessary to remove the rod from the apertures 55 of the ladder, take the ladder off of the platform 50, and then remove the upper support it from the ladder, after first removing the bolt 62 and the wingnut 53 from the member 6!. This can be done very quickly and easily. The apparatus is safe, compact, and strong, and accomplishes marked savings in both time and labor. By reducing the frequency with which a workman must ascend and descend a ladder, the danger of accidents therefrom is correspondingly reduced.

Various changes and modifications may be made without departing from the spirit of the invention, and all of such changes are contemplated, as will come within the scope of the claims.

What I claim is:

1. In a supported ladder assemblage, a shiftable carriage comprising: a frame for supporting the base of said ladder; a pair of spaced coaxial wheels rotatably mounted at the front end of said frame; a pair of spaced coaxial wheels rotatably mounted at the rear end of said frame; an anchor remote from the carriage; a brake member pivotally mounted on the front endof said frame and normally urged by gravity into braking engagement with both of said front wheels; a brake member pivotally mounted on the rear end of said frame and normally urged by gravity into braking engagement with both of said rear wheels; and a line accessible from an elevated position on the ladder and connected to said front and rear brake members and to said anchor for pivoting said brake members out of engagement with said wheels and for thereafter moving said carriage toward said anchor in response to a pull on said line.

2. In a supported ladder assemblage, a shiftable carriage comprising: a, main frame for supporting the base,v of said ladder; an. auxiliary frame, pivotally connected to the front end of. said.

riage; a brake member pivotally mounted on said auxiliary frame and normally urged by gravity into braking engagement with both Ofl said front wheels; a brake member pivotally mounted on the rear end of said main frame and normally urged by gravity into braking engagement with both of said rear wheels; and a line accessible from an elevated position on the ladder and connected to said front and rear brake members and to said anchor for pivoting said brake members out of engagement with said wheels and for thereafter moving said carriage toward said anchor in response to a pull on said line.

3. In a supported ladder assemblage, a shiftable carriage comprising: a turntable for removably supporting the base, of said ladder; a frame for supporting said turntable; a pair of spaced coaxial wheels rotatably mounted at the. front. end of saidframe; a pair of spaced coaxial wheels rotatably mounted at the rear end of said frame; an anchor remote from the carriage; a brake member pivotally mounted on the front end of said frame and normally urged by gravity into braking engagement with both of said front wheels; a brake member pivotally mounted on the rear end of said frame and normally urged by gravity into braking engagement with bothv of said rear wheels; and a line accessible from an elevated position on the ladder and connected to said front and rear brake members, andto said anchor for pivoting said brake members out of engagement with said wheels and for thereafter moving said carriage toward said anchor in response to a pull on said line.

a 4;. In;a;-. supported ladder assemblage; a1;shittable carriage; comprising: a; turntable, for: supporting the, base of saidv ladder; a main frame for. supporting said turntable; anauxiliary frame pivotally connectedto the front. end of said: main frame, and rotatable: in a horizontal plane; a;

pair of -spaced coaxial wheels rotatably mounted on said-auxiliary frame; a pair of. spacedcoaxial wheelsrotatably mounted at the rear endofsaid main frame; an anchor remote. from the carriage; a: brake member pivotally mounted on said. auxiliaryframeand; normally urged by gravity into braking engagement with both of said front. wheels; a brake member pivotally' mounted on the rear end of said main frame and normally urged by gravity into, braking engagement with both of said rear, wheels; and a line accessible, from. an elevated position on the ladder and con-- nectedato. said front and rear brake members and tosaid anchorfor pivoting said brake membersi out1 of. engagement. with said Wheels and for thereafter moving said carriagev toward saidanchor in response-to a pull on said: line:

FRANK MEI-IRINGER.

REFERENCES. CITED;

The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 972,001 Holdorf. .Oct. 4', 1910.- 1,004,284 Lehmann Sept; 26, 1911. 1,447,092 Larson Feb. 27, 1923- l,503,58l Fleming Aug..5j, 1192 1, 576,695 Weber Mar. 16, 1926 1,926,697 Murphy- Sept. 12., 1933 1,997,462 Hansen M Apr. 9, 1935 2,046,5l6 Johnson July 7,1936- 2-,27-2,642 Owen Feb. 10, 1942' 2,499,091 Brubaker Feb. 28, 1950

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