US2902110A

US2902110A - Ladder construction

Info

Publication number: US2902110A
Application number: US733641A
Authority: US
Inventors: Lawrence A Eickholdt
Original assignee: HOMER C WIXSON
Current assignee: HOMER C WIXSON
Priority date: 1958-05-07
Filing date: 1958-05-07
Publication date: 1959-09-01
Anticipated expiration: 1976-09-01

Description

Sept. 1, 1959 Filed May 7, 1958 A. 4 E'ICKHOLDT 2,902,1 10

LADDER CONSTRUCTION 2 Sheets-Sheet 1 38 v E J INVENTOR.

IAWRENCE A. EICKHOLDT mw m ATTORNEYS Sept. 1, 1959 L. A. EICKHOLDT LADDER CONSTRUCTION 2 Sheets-Sheet 2 Filed May 7. 1958 INVENTOR.

LAWRENCE A. EICKHOLDT Y ATTORNEYS LADDER CONSTRUCTION 'Lawrence A. "l'lickholdt, Inkster, Mich, assignor of fifty percent to Homer C. Wixson, Livonia, Mich. Application -May 7, 1958, Serial No. 733,641 Claims. (Cl. 182-13) sisting of two ladder sections which'are slidably joined together so that the upper ladder section may be raised 'or lowered relative to'the other section, to thereby adjust the overall height of the ladder. Where such a ladder is used along a wall or the like, the user must constantly climb down the ladder, pick it up, and move it from one spot to another along the' wall.

Thus, it is an object-of this invention to form a two sec- 'tion extensible ladder, 'wherein the ladder may be moved sideways along the side of the wall against which the ladder is rested, 'and wherein the movement may be actuated and controlled by a person who is located at the very top of the ladder. p

A further object of this invention is to provide a track system wherein the ladder is supported upon a track which track tilts and .holds the ladder tilted against a vertical surface. 7 r p Yet a further objeet of this invention is to provide an r mr dv 41 115. vv o movin nd ee s t m ments-of. azladder in a direction transverse tofthe-iladder, which means is operable at all times regardless of the relative position of the t'wo laddersect ions' of which the ladder ii s cbn rposed... 1-

Still a further object of this invention is to provide a wheeled carriage for supporting a ladder and for moving the ladder transversely.

These and other objects and advantages will become apparent upon reading the following description of which the attached drawings form a part.

With reference to the attached drawings, in which:

Fig. l is a perspective view of the ladder construction hereof.

Fig. 2 is an enlarged view, taken in the direction of arrow 2 of Fig. 3, showing the rear elevation view of the ladder.

Fig. 3 is a perspective view of the carriage, per se.

Fig. 4 is an enlarged fragmentary side view taken in the direction of arrow 4 of Fig. 1.

Fig. 5 and Fig. 6 show the sprockets for moving the ladder and are taken in the direction of arrow 5 and arrows 66 of Fig. 2, but as if looking down from the front of the ladder.

Fig. 7 and Fig. 8 show fragments of the top of the leg of the lower ladder section and the bottom of the leg of the upper ladder section and their sprocket supporting brackets, respectively.

With reference to the drawings, the construction consists generally of a ladder 10, a support carriage 11 for the ladder, tracks 12 upon which the support carriage may ride, and a control and operating means 13. Each of these elements will be separately described.

The ladder consists of a lower ladder section 15 and United States Patent 0 "ice hold the two ladder sections in face to face contact and permits the upper ladder 16 to be adjusted relative to the lower ladder 15 for extending and adjusting the height of the ladder. This type of construction, including the brackets 17 for interconnecting and holding the two ladder sections are conventional, and thus, no further description; will be given for these parts since they, per se, form no part of this invention.

As illustrated in Fig. 3, the-carriage consists of a backing strip 20 upon which a pair of sockets 21 'are permanently secured. The-sockets are mounted on the backing s'trip by means of sleeves 21a, and thus rotate relative to theaxis of the backing strip. The two legs-of the lower ladder 15 are removably fitted into the sockets 2'1 and held in place by pins 2Tb (see Fig. 2) so that the ladders are removably mounted upon the carriage. Suspended below-the backing strip 20 are a pair of axles '22 and 23 upon which wheels 24 are mounted. The axle 22 rotates with the wheels 24 and is rotatably supported 'by means of the braces 25. The axle '23 is likewise supported by braces 26.

As shown in Figs. '1 and 4, the track 12 consists of an inside rail 30 and an outside rail 31 connected by cross strips 32. The inside rail is considerably lower in height than the outside rail 31 so that when the carriage wheels 24 ride upon the rails, the carriage is tilted at an angle to the vertical and the ladder, which is mounted in the sockets-'21, is likewis'e til-t'ed at angle to the vertical.

At the top of the ladder a pair of rollers 33 are mounted. These rollers rotate in a direction transverse to the plane -of the ladder, so that the ladder can move sideways withth'e rollers 33 bearing againstasupport wall 54 and rolling along the wall.

In order to move the ladder sideways, -e.g. parallel to the support wall, means consisting of four sprockets interconnected by an endless chain is provided. The top sprocket 35 is connected to theitop of one leg of the upper ladder 16 by means of a bracket 35a connected to said leg. A SCOTld sprocket 36 is connected by bracket 36a to the :other leg but at the bottom thereof- A third sprocket T37 .is oarriedzbybracket 3711*01141161019013 the leg of *the lower section 1*5v :be'n'eath sprocket 36. The tourth sprocket .38

is mounted upon axle 22 for rotation therewith so that rotation of the sprocket 38 rotates the axle 22 and the wheel 24.

A chain 39 interconnects the four sprockets by passing over the top of the sprocket 35 around the outside of the sprocket 36 over the top of the sprocket 37 and around the sprocket 38. A handle 40 is connected to the upper sprocket 35 so that the handle may be manually rotated to rotate sprocket 35, to move the chain and thereby cause rotation of the sprocket 38 and the wheels 24.

To adjust the chain tension,

sprocket brackets

36a and 37a are movably mounted on their respective ladder sections, as follows:

The top ofleg 15a of the lower ladder section 15 and the bottom of the leg 16a of the upper ladder section 16, are indented with channels 44. Lugs 46, formed on the brackets, fit within the indentations 44 and a pin 47 may be removably secured in one of a number of openings 48 in the ladder legs.

Note that bracket 36a is similar to bracket 37a, with the exception that bracket 36a is provided with an extension 52 arranged to pass around the leg of the lower ladder section 15, whereby the

sprockets

35, 36, and 37 are all positioned in the same plane.

In operation, the two ladder portions are arranged with the legs of the lower ladder portions in the sockets of the carriage and with the carriage upon the track 12. The track 12 may be permanently mounted near a wall where the ladder is frequently used or may be formed in a number of sections and assembled in front of any wall.

The ladder is adjusted to the desired height and, because of the tilt of the carriage due to the different height rails, the ladder leans against the wall with the chain 39 being substantially in one plane. The worker using the ladder may then move the ladder in a direction parallel to the wall, as he desires, by simply turning the crank 40.

This invention may be further developed within the scope of the following attached claims.

Accordingly, this description should be read as being merely illustrative of an operative embodiment of this invention and not in a strictly limiting sense.

I claim:

1. A ladder construction comprising a lower base ladder and an upper ladder, both arranged in face to face relationship with the upper ladder being carried by and being extensible from the lower ladder; means for moving the ladders in a sidewise direction, said means comprising a wheeled carriage upon which the lower ladder is mounted, the wheels of the carriage being mounted upon axles, at least one of the axles being rotatably mounted upon the carriage with the wheels mounted upon said one axle being fixed thereto and the axles being arranged approximately normal to the plane of the ladders, and also comprising a chain and sprocket type mover in the form of a pair of sprockets rotatably mounted on the upper ladder, one at the top of one leg and the other at the bottom of the other leg thereof, and a sprocket rotatably mounted on the leg of the upper end of the lower ladder corresponding to said one leg of the upper ladder, all three sprockets being on the same face of the ladder, and a fourth sprocket fixed to said one of the wheel axles, the sprockets being interconnected by an endless chain which runs over the top sprocket of the upper ladder, then under the upper ladder bottom sprocket, then over the top of the lower ladder sprocket, and finally under the wheel axle sprocket, and handle means connected with the top sprocket of the upper ladder for rotating the sprocket and thereby rotating the wheel axle to thus rotate the carriage wheels and move the ladders.

2. A construction as defined in claim 1 and said carriage comprising two spaced axles and a transverse backing, each axle carrying a pair of Wheels, the axles being connected to said transverse backing, said backing having attached sockets for removably receiving the legs of the lower ladder.

3. A construction as defined in claim 2 and including a double rail track upon which the wheels ride, with one rail being higher than the other, thereby tilting the carriage and the ladder at an angle to the vertical,

4. A construction as defined in claim 1 and wherein the bottom sprocket of the upper ladder is carried by a bracket which is movably connected to said other leg of the upper ladder and the sprocket of the lower ladder is likewise carried by a bracket which is movably connected to the lower ladder and which positions. its sprocket in the same plane as said bottom sprocket, the brackets including means allowing for their adjustment along the length of their respective ladders for adjusting the tension of the chain.

5. A ladder construction comprising a lower ladder and an upper ladder arranged in face to face contact with and forwardly of the lower ladder, and secured thereto for movement relative thereto for adjusting the combined length of the two ladders, means for moving the ladders transversely, said means comprising a carriage and an operator, the carriage consisting of a plurality of wheels mounted upon axles rotatably connected to the legs of the lower ladder, and the operator consisting of four sprockets: a top and bottom sprocket rotatably mounted at the top and bottom of the upper ladder on opposite legs thereof and on one face thereof, and a sprocket connected to the top of the leg of the lower ladder corresponding to the upper ladder top sprocket leg, and positioned in the plane of the afore mentioned sprockets, and a sprocket fixed to one of said axles; an endless chain interconnecting the sprockets as follows: first, around the upper ladder top sprocket and then around the bottom sprocket, then over the top of the lower ladder sprocket and finally around the axle sprocket, and manual crank means for rotating the top sprocket to thereby rotate the axle sprocket and move the wheels and ladder.

References Cited in the file of this patent UNITED STATES PATENTS 1,142,806 Fenton June 15, 1915 1,969,628 Skeenes Aug. 7, 1934 FOREIGN PATENTS 537,641 Germany Nov. 6, 1931