US1582794A - Telescoping extension ladder - Google Patents

Description

April 27 1926. v 1,582,794

C. W. SMITH ET AL TELESCOPING EXTENSION LADDER Original Filed p 7 1924 2 Sheets-Sheet 1 mgmgm gwventots April 27 1926. 1,582,794

C. W. SMITH ET AL TELES COPING EXTENS ION LADDER Original Filed pt. 2'7. 2 2 Sheets-Sheet 2 Patented Apr. 27, 1925.

UNITED STATES PATENT OFFICE.

CHARLES W. SMITH, OF BLUFFTON, AND EARNESI L. THOMIPSON, 0F FORT WAYNE,

INDIANA.

TELESCOPING EXTENSION LADDER.

Griginal application filed September 27, 1824, Serial No. 740,236. Divided and this application filed March 8, 1928.

To (ZZZ 207mm 714' may concern:

Be it known that we, CHARLES 1V. SMITH and Ennnrsr L. THOMPSON, citizens or the United States, residing, respectively, at Blutlton, in the county of Wells and State of Indiana, and Fort Jayne, in the county of Allen and State of Indiana, have invented certain new and useful Improvements'in Telescoping Extension Ladders; and we do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

Our invention relates to power-driven fire trucks, but more particularly to motor actuated ladders mounted upon such trucks, and to means whereby the main and extension ladder sections may be quickly and ace ratcly elevated into operative position when desired or required.

The present application is adivision or our co-pending application Serial No. 740,- 236, iiled September 27, 1924-,

An object of our invention is the production or fire-fighting apparatus of the character indicated, wherein is combined extreme simplicity of construction, durability and etliciency of the highest obtainable degree, the same power plant being employed for locomotion and for ladder manipulation with speed, accuracy and precision.

With the foregoing and other objects in view the present invention ill be hereinafter particularly described and then pointed out by the claims following.

In the accompanying drawings which form part of this application for Letters- Patent, and whereon corresponding numerals indicate like parts in the several views:

Figure 1 is a top plan view of this invention showing the major part of the truck chassis, the ladder sections, and ladder operating mechanism;

Figure 2 is a fragmentary view showing in side elevation the ladder sections in a raised vertical position, but still nested or collapsed;

Figure 3 is also a fragmentary vertical sectional View taken onthe line 33 of Figure 2, showing thelower end of the lower- Serial No. 93,162.

most ladder section raised to a vertical position;

Figure 4: is a horizontal sectional view tlniough one ladder section; and

Figure 5 is a fragmentary view also in horizontal section of one side of a series of ladders when nested or collapsed into the position indicated by Figure 2.

Reference being had to the drawings and numerals thereon, 1 indicates a truck chassis, which may be of any suitable construction or proportions, mounted upon wheels 2, only two of which are shown by the. drawings, and provided with a suitable power and propulsion plant such as shown diagrammatically at 3. fit as side of the main driving shaft 1 and bracketed to the truck frame 1 in suitable bearings is a power transmission shaft 5, driven from the engine 3 by agency of a sprocket 6 and chain 7, and provided at its other inner end with two fixed beveled pinions 8 and 9. The former of these pinions 8 meshes constantly with a beveled gear 10 carried by a short stub shatt mounted in a journal box 11, the said shat't having at its opposite end a fixed beveled pinion or spur wheel 12. This spur pinion l2 meshes constantly with two oppositely disposed driven gears 13 and 1% mounted loosely upon a worm-shaft 15, separated by the spacing sleeve 16, and provided upon their outer tacos with clutch members 17 and 18, respectively, which rotate constantly in opposite directions with the said gears, the while constituting a reversible clutch.

Splined upon the said worm-shaft 15, so to permit of slight longitudinal movement, are the movable clutch members 19 and 20, arranged and adapted to be actuated by a rectangular frame or compound lever 21, pivoted as at 22, and provided with a handle 23 by which controlled, to move one or the other of the clutch members 19 or 20, into cooperating engagement with its particular clutch member 17 or 18 according to the requirements as will more clearly appear in connection with a description of operation to follow.

The shaft 15 rotatably journalled atits ends in transverse frame members'Qt, 25, is provided upon its innermost end with a worm 2G meshing with a segmental rack 2'4", the latter keyed to a shaft 29 which in turn is supported in uprights 29, 29, rising from the side sills of the truck chassis 1 as best shown by Figures 2 and 3. Rigidly secured to the said transverse .shaft 28 also are the side rails of a main ladder section 30, which normally occupies the horizontal position indicated by dotted lines in Figure 2 of the drawings, but is capable of being rotated into vertical position as will later appear.

By preference the main ladder section 30, as also the co-acting fly ladders 31, 32 and 33, are made of sheet metal substantially as indicated by Figures 4 and 5 of the draw ings. That is to say, their side rails are of tubular form made up of reversely arranged channels 34 and 35, the latter enclosing the former, and connected by through bolts 36 surrounded by tubular spacing membersv 37, as clearly shown by Figure 4. Between the inner sides of ladder members and the outer surfaces of the members 34 of each ladder section, there is provided acontinuous longitudinal clearance or space 38, into which is loosely and slidably fitted the member 35 of the adjacentladder sections, and in this manner the several ladder sections 30, 31, 32 and 33 are interlinked as shown by Figure 5, in telescopic relation. At suitable intervals between the tie rods or bolts 36 the side rails of all ladder sections are also connected by ladder rungs 39, while near opposite ends of all ladder sections, upon their outer faces, are pivotally mounted inner and outer hoisting pulleys or sheaves and 41 respectively, for purposes that will later appear. The uppermost of the fly ladders 33, has no upper sheaves 41, nor are there sheaves 40 at its opposite end, but in place of the latter at both sides of this ladder section 33, there are openings through the ladder sides and in these are journalled pulleys 41 occupying positions; at right angles to the sheaves 41.

Journalled in opposite sides of the truck chassis 1 as at 42, 2, is a double Windlass or hoisting reel 43, 43, mounted loosely upon a transversely positioned driven shaft 44 having keyed upon one end a driven gear constantly in mesh with the driving pinion 9 hereinbefore mentioned. At its opposite end the Windlass or hoisting reel 43 is provided with a clutch 46, and a clutch lever 47, by which said reel can be temporarily locked to its constantly revolving shaft 44, or instantly released therefrom as occasion requires. and upon one side of reel 43 is a brake drum 48 over which runs a band brake 49, operated by a brake-lever 5O pivotally mounted upon the truck frame for retaining the ladder sections in a distended position or for lowering them back to their Adjacent the reel clutch 46- normal nested position, the brake lever being fitted with an ordinary pawl and cooperating rack, indicated diagrammatically at 51 for holding the fly ladders in Opera tive position after raising.

This being a description of our present invention in one form of embodiment, its use and operation in the form shown and described will now be briefly set forth as follows:

The truck having been driven to its point of service in the usual manner under the power of its engine, the brakes are applied, and the engine de-clutched or disconnected from its driving or propelling mechanism. Power now transmitted to the auxiliary shaft 5, by agency of such means as chain and sprocket 7, 6, drives the gears 13 and 14 in reverse directions by agency of pinions 3 and 1.2 and the intermediate gear 10. Normally the said gears 13 and 14 run idly upon the shaft 15, but when now the clutch members 13 and 20 are interlocked by a throw of handle 23 in a rearward direction, the said shaft 15 and its worm 26 operate to rock segment 27 on its center from the position indicated by dotted lines of Figure 2, to that indicated by full lines, thereby elevating the main and fly- ladder sections 30, 31, 32 and 33, still clustered, nested or withdrawn, to the vertical position shown by full lines in said Figure 2.

The fly ladders 31, 32 and 33 may now be quickly extended or shot upward from the main ladder 30, by agency of the ladder extension clutch 46, and its controlling lever 47. A throw of this lever 47 instantly couples the double hoisting reel 43, 43 to its supporting shaft 44, the latter constantly rotated by drive shaft 5 through pinion 9 and the gear 45.

This accomplished, both ends of the continuous hoisting wire cable 52 are quickly coiled upon the power driven reels 43, 43, from which they pass over guide sheaves 53, adjacent the main ladder section 30, thence over oppositely disposed sheaves 41, 41, at the upper end of ladder 30, thence over sheaves 40, 40 and 41, 41, upon opposite ends of fly-ladder 31, over similar sheaves 40, 40 and 41, 41 upon opposite ends of ladder section 32, and finally over sheaves 41, 41 located in openings near the bottom and through the side rails of the outermost ladder section 33.

By this means the ladder sections are quickly extended, flanges 35, 35 of each guided and running freely in the spaces or grooves 38, 38 provided in adjacent sections for their interconnection. Upon reaching the desired elevation or extension, clutch 43 is disconnected, and the hand brake 4849 being simultaneously set by a throw of the brake lever 50, is there retained by action of the pawl and ratchet mechanism 51, until manually released for the purpose of returning the ladder sections to normal positions.

When thus released the ladder sections are lowered or returned to a clustered vertical position by gravity under control or" the brake lever 50, the operator preventing too rapid return by agency of the brake band i9 applied to the brake drum 48 with more or less pressure according to circumstances, and thus gradually paying out the hoisting cable from the reels e3, as required.

Having reached the position indicated by Figure 2, the ladders are next returned to their normal horizontal position in the following manner A throw of the reversible clutch lever 23 in a forward direction now serves to interlock the clutch members 17 and 19 thereby rotating the worm-shaft 15 in the opposite or reverse direction from that hereinbefore described, at the same time rocking the scg mental rack 27 from the position indicated by full lines, to that indicated by dotted lines, in Figure 2 of the drawings, thus lowering the ladder sections upon the transverse shaft 28 as a center into their normal horizontal position.

Having thus described our invention in one operative form of construction, what we new claim and desire to secure by Letters Patent is:

1. In an extension ladder, a series of ladder sections, each section consisting of side rails and connecting rungs, each side rail consisting of a pair of channel iron strips of different widths, the strips of each rail being reversely arranged with the wings of the strips spaced apart to form parallel grooves at the opposite edge portions of the rail, the wings of one of the strips of one rail extending into the grooves of two adjacent rails to provide a sliding connection between the rails.

2. In an extension ladder,a series of ladder sections slidably interconnected and each consisting of a pair of side rails and cross rungs, each side rail consisting of a large channel iron strip and a small channel iron strip, the Webs of the strips being spaced apart and the wings of the strips extending in opposite directions to provide at opposite sides of each rail a pair of flanges and a pair of grooves, the flanges and grooves of adjacent ladder sections being slidably interconnected to permit the ladder to be extended.

3. An extension ladder comprising main and extension sections having tubular side rails, each rail formed of reversely arranged members of substantially U-shape held in fixed relation by through bolts connecting opposite sides of each ladder section, in combination with longitudinal flanges upon each of said side rails arranged and adapted to run in. grooves upon the corresponding side rails of adjacent ladder sections.

l. An extension ladder including in combination a series of slidably interconnected ladder sections, each section consisting of side rails and rungs, each rail consisting of channel irons of different sizes with the wings of the smaller channel iron extending into the larger channel iron and abutting against the web of the latter, the wings of the two channel irons being spaced apart to provide grooves at the opposite edge portions of the rail.

In testimony whereof we afiix our signatures.

CHARLES SMITH. EARNEST L. THOMPSON.

Images