US2189432A - Stepladder - Google Patents

Description

Feb. 6, 1940. H. T. MOORE ET AL S TEPLADDER Filed Dec. 17, 1958 INVENTOR.

,7%0 ORE l l ZZ ATTORNEYS a will! Patented Feb. 6, 1940 f' 'f UNITED STATES ATENT OFFICE STEPLADDER Henry T. Moore and Frank F. W. Perrott,

Greenfield. Mass.

Application December 17, 1938, Serial No. 246.309

1 Claim. (Cl. 228-15) This invention relates to a stepladder attach- The stepladderfshown in the drawing comment. prises a top plank 5, and vertical supports 6, 1, An object of the present invention is the pro- 8, and 9. Which are interconnected by the IOClS v vision of simple, inexpensive, and effectively opl and il. f A tOlO Stell' i8 and lOWeI' Steps l2 t0 l5 5 erable means for propelling `a stepladder while are Carried by the Slippeits 8 and 9, While a red 5 the latter is in use, H extends between the supports and 1.

Another object, is the provision of a, device 'A horizontal frame lil used for carrying the imthrough the use of which a painter or any other Diements of the Operator is carried by the Supoperator may conveniently move a ladder from Ports 5 and 'i andiS ccnnected tc .the Step |5- place to place without having to descend there- The Supports 8 t0 8 are carried by the WheelS 10" from. l I i9 to 22. The wheels I9 and 20 are mounted A further object is the provision of a stepupon the wheel axle 23, while the wheels 2| and ladder having propelling means operable from a 22 are rotatable along with the wheel axle 24.

position on top of the ladder. The attachment usedfor driving the wheel Other objects will become apparent in the axle 24 comprisesl a crank 25 having a handle 26 15 course of the following specification. which is situated close to the top plank 5 of the The objects of the present invention may be ladder and which may be easily grasped by the realized through the provision of a stepladder Workman While he iS Situated On the tOD 0f the attachment having a crank or handle situated ladder. The Crank 25 iS made 0f a Single piece close to the top of the ladder at the place where with the shaft 21, which is rotatably mounted in 20,

the operator is positioned while he is working on bearings 23. 29, and 38. The bearings 28 and the. ladder, so that the crank can be easily turned 30 extend through the Supports 8 and 9, respecby the operator without it being necessary for tively. While the bearing 29 iS attached by the bal him to leave his position or disturbing him in his 3l to the upper Plank 5- work. Any suitable transmission means may be A bevel gear 32 is mounted upon the shaft 21 25 used for transmitting the movement of the crank and is rotatable therewith. The bevel gear 32 to the wheels of the ladder for the purpose of meshes with the bevel gear 33, which is rotatable propelling the latter. Preferably, this transmisalong with an .elengated Shaft 34. The Shaft 34 sion consists of two pairs of bevel gears which are eXtendS through Openings provided in the Steps interconnected by a rotary shaft and which transl2 t0 I6 and iS carried by SleeVeS 35 and-36, Which 30 mit the rotation of the crank to a wheel axle of are attached to the Support 9. the ladder. The ladder is stopped by a brake The lower end of the shaft 34 is rmly conhaving a brake handle, which is also located close nected with a bevel gear 3T, meshing With a bevel to the workman, while the latter is in his workgear 38 which is mounted upon the shaft 24 and ing position upon the ladder. The movement of iS rotatable along with that shaft. 35

the brake handle is transmitted by means of a Due to the described arrangement, the workbrake rod to a brake shoe which may be brought man may easily drive the wheel axle 24 by rotattobear upon the same wheel axle. ing the crank 25 without leaving his position The invention will appear more clearly from upon the top of the ladder. 40 the following detailed description when taken in The braking device used for stopping the move- 40 connection with the accompanying drawing, ment of the ladder comprises an elongated brake showing by way of example a preferred embodirod 39 having a brake shoe 40 situated close to ment of the inventive idea. a sleeve 4I rotatable along with the wheel axle In the drawing: 24. The brake shaft 39 extends through open- Figure 1 is a perspective View of a stepladder ings provided in the steps I2 to I 6. 45

provided with an attachment constructed in ac- The upper end of the rod 39 is preferably procordance with the principles of the present invided with a rounded knob or head 42 (Figs. 3 vention; and 4), which is screwed upon the threaded end Figure 2 is a vertical section through the top of the rod. A coil spring 43 surrounds the rod portion of the ladder along a plane indicated by 39 and is situated between the head 42 and the 50 the line 2-2 of Figure 1 on a larger scale; step I6. The spring 43 tends to maintain the Figure 3 shows in section and on a larger scale rod 39 in the raised position shown in the a portion of the brake handle; and drawing.

Figure 4 is a view along the line 4-4 of Fig- A brake handle 44 is provided with two downure 3. wardly extending projections 45 and 46, which 55 CII Cab

are pivotally mounted upon a pin 41 carried by the angle irons 48 and 49. The angle irons 48 and 49 are attached to the step I6 by the screws 50. The projections 45 and 46 are provided with bent flanged portions 5l and 52.

When an operator who is seated upon the top plank 5 of the ladder desires to move the ladder, he turns the handle 26, thereby rotating the crank 25 and the shaft 21. The bevel gear 32 rotates along with the shaft 21 and transmits its rotation to the bevel gear 33 and the shaft 34. The bevel gear 31 rotatable along with the shaft 34 transmits the rotation to the bevel gear 38, which is rotatable along with the wheel axle 24. Consequently, a rotation of the crank 25 will result in the rotation of the wheels 2| and 22, so that the stepladder will move in the desired direction.

In order to stop the ladder, the operator moves the brake lever 44 downwardly. Since the brake rod 39 is provided with a head 42 which is in engagement with the lever 44, the rod 39 will also move downwardly and the brake shoe 40 will press against the sleeve 4|, thereby stopping the rotation of the shaft 24.

As soon as the manual pressure upon the brake lever is released, the spring 43 will return the rod to its original inoperative position shown in the drawing. The rod 39 will be maintained this inoperative position by the projections 5I and which engage the side surfaces of the supports 'i3 and 49.

It is apparent that the specific illustration shown above has been given by way of illustration and not by way of limitation, and that the structure above described is subject to wide variation and modication without departing from the scope or intent of the invention, all of which variations and modifications are to be included within the scope of the present invention.

What is claimed is:

In combination with a ladder having a top step, supports carrying said top step and having outer and inner sides, and lower steps carried by said supports; a rotatable wheel axle carried by said supports, and wheels carried by said wheel axle; a shaft extending through openings formed in said lower steps, a gear drive operatively connecting one end of said shaft with said wheel axle to drive the latter, a manually operable crank situated below said top step and at an outer side of one of said supports, a second shaft connected with said crank and driven thereby, the second-mentioned shaft being carried by said supports and extending below said top step, a second gear drive operatively connecting the second-mentioned shaft with the other end of the first-mentioned shaft to drive the latter, a ring carried by said wheel axle and rotatable therewith, a movable brake shoe adapted to engage said ring to stop the rotation of said Wheel axle, a brake rod movable with said brake shoe and extending through openings formed in said steps, a brake lever, means connected with said brake rod and engaging said brake lever for pressing said brake shoe against said ring when said brake lever is actuated, means connected with the first-mentioned means for returning said brake shoe to an inoperative position when said brake lever is released, and means supporting said brake lever below said top step.

HENRY T. MOORE. FRANK F. W. PERRO'I'I.

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