US545643A - Extension fire-ladder and truck - Google Patents

Description

(No Model.) E 2-Sheet sSheet 1f A. B. OAIRNES.

EXTENSION FIRE LADDER AND TRUCK.

No. 545,643. Patented Sept. 3,1895.

2 Sheets-Sheet 2.

(No Model.)

A. B. GAIRNBS. EXTENSION FIRE LADDER AND TRUCK.

UNITED STATES PATENT OFFICE.

ALEXANDER B. CAIRNES, OF SAN DIEGO, CALIFORNIA.

EXTENSION FIRE-LADDER AND TRUCK.

SPECIFICATION forming part of Letters Patent No. 545,643, dated September 3, 1895. Application filed January 2, 1895- Serial No. 533,609. (No model.)

To aZZ whom it may concern.-

Be it known that I, ALEXANDER B. CAIRNES, a citizen of the United States, residing at San Diego, county of San Diego, State of California, have invented an Improvement in Extension Fire-Ladders and Trucks; and I hereby tion, which will be more fully explained by reference to the accompanying drawings, in which Figure l is a side elevation of the truck, showing the ladders partly raised and a mechanism for raising them. Fig. 2 is a section through the turn-table on the line y'y of Fig. 3. Fig. 3 is a plan of the same. Fig. l is a detail section of the braces and connections.

The object of my invention is to provide a ladder which is capable of being raised to any desired angle between the horizontal and per-' pendicular, and it may be extended to any practicable. distance by means of two or more supplemental ladders slidable upon the lowermost one, a. mechanism by which they are raised, extended, and turned about so as to reach any point with relation to the original position of the truck without changing the ladder, and also means for more rapidly performing these operations and steadying and bracing the ladders after they have been raised and turned to the desired position.

A is the frame of my apparatus, made of sufficient length to properly support the ladders B, O, and D, which are carried and operated thereon. This frame is mounted upon wheels E, properly arranged to turn to place the truck wherever it is desired. The ladders are preferably braced by truss-frames F, which strengthen and steady them against vibration. The foot of the lowermost ladder is pivoted to blocks G, which are slidable horizontally in a guide H, so that when the ladders are to be raised the sliding blocks will move along this guiding-track until the foot of the ladder is brought upon the turn-table, as will be hereinafter described.

In order to first raise the ladders from their horizontal position to stand at such an angle that they may be afterward brought to a vertical position by the proper mechanism, I have shown vertical racks I, which are slidable in guides J, fixed upon the sides of the truck-frame at a suitablepoint with reference to the foot of the ladders when they are lying flat. In the present case the racks and guides are somewhat nearer to the front of the frame and foot, of the ladder than the rear.

K are pinions fixed upon a shaft suitably journaled across the frame, and these pinions engage the racks I. Upon the upper ends of the racks I are forks or crotches L, and when the racks are raised these crotches engage stout projecting pins M upon the sides of the ladder, and thus raise the ladder about its foot as a fulcrum-point until it stands at a considerable angle with the horizontal, the foot of the ladder moving back along the guides. The pinion-shaft is operated by means of a socket wrench or handle, which is applicable to all the shafts that are to be turned during the operation of setting the ladders, and when theracks are raised they are retained at any point by means of a pawl N, which engages the teeth.

0 is a shaft, having upon it drums 0, about which ropes or cables P are adapted to wind, and also pawl and ratchet-wheels, as shown at p. This drum-shaft is journaled upon a turn-table Q, which is pivoted to turn in a horizontal plane at the rear end of the truckframe. In its normal position this turn-table is in line with the guides H, so that when the foot of the ladder has been moved to the rear to a sufficient distance to bring the foot of the ladder to an approximately vertical position thefoot of the ladder will then be upon the turn-table and clear of the stationary tracks upon the main frame. The ropes or cables P, which coil upon the drums of the drum shaft, have their opposite ends connected with oyebolts suitably fixed to the lower end of the ladder B or the movable blocks G. After the racks I have been raised and the rear end of the ladder partially raised in this manner the socket-wrench is trans ferred to the end of the shaft 0, and by turn- I it the foot of the ladder is'drawn toward the rear, and finally transferred to the turn=tabl'e, when the latter may be rotated so as to place the ladders in any desired position. The braces which hold the ladder while the foot is thus being drawn toward the rear consist 1 of screws R, the upper ends of which are connected with the pins M upon the sides of the ladder. The screw-threaded portion of these shafts enter long tubular sleeves S, and these sleeves have upon their upper ends nuts T, within which the screws are'turnable. The lower ends of the tubes S are pivoted toturn upon stout eyebolts U, which enter corresponding sockets "in the lower ends of the tubes, and have nuts or collars to, which prevent end motion, but allow the tubes to turn freely about them. The bolts U have eyes at the lower end, and these eyes fit loosely upon a horizontal shaft V on the rear endof the turn-table, so that the tubular shafts S may be raised or'depressed about this shaft V, While being turnable upon their own axis around the bolts U.

To the foot of each of the tubular shafts S is fixed a pinion W, and upon the shaft V are fixed corresponding bevel-gears a, which engage with the bevel-pinions WV, so that by transferring the socket-wrench to the end of the shaft V the latter and the bevel-gears a may be rotated and thus turn the tubes S. This operation is not performed until 'after the ladders have been raised into an essen= tiall y vertical position by means of thecables, as before described, the screw-shafts R and tubes S serving up to this time as braces to raise the ladders into that position, while the foot of the ladders is being drawn rearwardly until it arrives upon the turn-table. The braces and ladders then being entirely upon the turn-table, the angle of the ladders is regulated to suit requirements by turning the shaft V, and through the bevel-gears a and l W the tubes S are rotated, so that the nutsT will advance the screw-shafts R to lengthen or shorten the braces and thus adjust the position of the ladders to the desired angle. They may thus be moved from nearly fortyfive degrees on one side to beyond a perpendicular on the other side, the screws being right and left threaded. The turn-table Q has a stout central king-bolt b, by which it is united to a lower plate Q, which is permanently fixed upon the truck-frame and serves as a bed about which the upper table Q is turnable. The upper table has arms a, projecting to the rear, and theseserve as handles by-which it may be turned around, so as to place the ladders at any desired angle with the position of the truck. This may be done after the ladders are first raised into their essentially vertical position, and the adjustments by the screw shaft R may be made after the ladders are turned to stand in the proper direction, so as to allow them to rest against the building or other desired point of support.

and thus steady the apparatus when the ladders have been turned to an angle with the truck-frame and relieve the frame. The ladders maybe extended after having been raised to the vertical position, as shown in my former patent, N0. 527,94c 2, or in any other suitable or desired manner.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is-- 1. In an extension ladder, a wheeled truck frame having guides extending horizontally along it, a ladder adapted to normally lie in a horizontal position on the truck frame, with its foot end provided with blocks or travelers adapted to engage and move upon the guides, vertical guides on the sides of the truck frame at a point between the opposite ends of the ladder, when the latter is in its normal position, rack bars movable in said guides and supporting the ladder upon their upper ends and pinions engaging the racks whereby the latter are moved in vertical planes to lift the ladder out of its normal horizontal position to an inclined position to permit its being subsequently moved into a vertical or approximately vertical position, substantially as described.

2. In an extension ladder,a frame mounted upon wheels having longitudinal guides upon it, a ladder having blocks or travelers connected with its foot and movable in said guides, a vertically moving rack by which the ladders are raised to an inclined position about said travelers, a drum shaft journaled across the turn-table, ropes adapted to coil upon the drum having their opposite arms connected with the foot of the ladder, and braces having the lower ends fulcrumed upon the turn-table, and the upper ends connected with the ladder at points above its base whereby the moving of the foot of the ladder along the guides will raise it into an approximately vertical position.

3. In an extension ladder, the truck frame having longitudinal guides, blocks or travelers upon the foot of the ladder movable 'on said guides, a means comprising vertically movable rack bars at the sides of the truck frame and engaging the ladder at points between its extremities for first raising the ladders to an angle, winding drums and cables extending therefrom to the foot of the ladders and braces connected with the ladder so as to raise it to a vertical position when the foot is drawn toward the braces, a turn-table pivoted upon the opposite portion of the truck frame having the winding drum shaft journaled across the front end of it, said table having tongues continuous with the guides upon the main frame whereby the foot of the 545,643 g a a ladder may be transferred from the main frame to the turn-table when it has been raised to the vertical position.

4. In an extension ladder, a truck frame having longitudinal guides, a ladder having blocks or travelers at its lower end movable upon said guides, a turn-table pivoted at the opposite end of the frame having tracks adapted to stand in line with the guides of the main frame, a drum shaft journaled across the turn-table, cables extending from the drums to the foot of the ladder, a mechanism comprising vertically movable rack bars engaging the ladder at points between its ends and pinions for actuating the bars by which the ladder is first-raised about said blocks or travelers to an angle with the truck frame, means for rotating the drum shaft so that the foot of the ladder and its connected blocks or travelers are drawn along the guides and transferred therefrom to the turn-table, braces fulcrumed upon a shaft at one end, having the other ends connected with the ladder so as to raise it when the foot is moved toward the turn-table, said braces consisting of screw-shafts extending into tubular sleeves, with nuts which advance the screw shaft in either direction when the sleeves are rotated, means for rotating the sleeves consisting of bevel pinions fixed to their lower ends and corresponding bevel gears fixed upon the shaft journaled upon the turn-table, and engaging the pinions, so that the rotation of the shaft will turn the tubes, and'thus advance the screw shafts in either direction to lengthen or shorten the braces and change the angle of the ladder.

5. In an extension ladder, a truck frame having longitudinal guides, travelers connected with the foot of the ladder and movable on the guides, a turn-table pivoted to the opposite end of the frame with braces attached thereto and connected with the ladders, winding drums upon the turn-table and ropes extending therefrom to the foot of the ladder, whereby the latter maybe drawn upon the turn-table and raised by the braces into a vertical position, said turn-table being revoluble about its central king bolt so as to f change the position of the ladders with reference to the truck after they have been transferred to the turn-table, and extension arms .or braces extending from the turn-table to the ground as herein described.

In witness whereof I have hereunto set my hand. J

ALEXANDER B. GAIRNES. Witnesses:

L. 0. MIX, J NO. P. BURT.

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