US2312833A - Fire escape elevator ladder - Google Patents

Description

March 2, 1943. LGRAHAM FIRE ESCAPE ELEVATOR LADDER Filed Dec. 4, 1941 8g saiah Graham.

attorney Patented Mar. 2, 1943 UNHTED STATES T @FHQE 2,312,333 ems ESCAPE ELEVATOR LADDER Isaiah Graham, ()maha, Nebr.

Application December 4, 1941, Serial No. 421,678

1 Claim. (Cl. 2278) This invention relates to ladders and more particularly to fire escapes.

It is an object of the invention to provide a fire escape which may be readily leaned against an exterior wall of a burning building useful for a plurality of purposes including ordinary use as a ladder and use for readily lowering occupants of upper floors of a burning building safely to the ground, the means for said latter use also including means for elevating firemen to the upper end of said ladder.

Another object of the invention is to provide braking means for regulating a lowering of an escape car employed.

Other and further objects and advantages of the invention will be understood from the following detailed description thereof.

In the drawing:

Figure l is a front vertical elevation of a fire escape elevator ladder depicting the preferred embodiment of the invention, certain portions thereof being broken away and others showing partially in section.

Figure 2 is a side elevation of the said embodim'ent.

It is well known that heretofore it has often happened, at times when a conventional ladder is leaned against a wall of a burning building, such as the upper floors of a hotel or the like for providing a means of escape of occupants, that the latter are often too excited or otherwise incapacitated to avail themselves of said ladder for escape and without the assistance of firemen, whereby it has often happened that a fireman must first climb the ladder for carrying an occupant of a burning building down the ladder. For said carrying purposes most firemen are equipped with snap hooks attached to their belts and convey a similar harness to the top of said ladder which they secure around occupantslater attaching said snap'hooks to said harnesses whereby firemen can use both hands for descending the ladder while people are securel'y attached to said belts. The said present practice requires firemen whose said rescue efforts often could be better utilized for other purposes. Also it has often happened that where a person is being transported by a fireman down a ladder without said harness that in instances where said ladder is covered with ice both the fireman and said person have slipped from the ladder and become injured. Also it has happened that a fireman upon reaching the top of the ladder intending to harness a person, as above described, has found that through inadvertence he is not provided with said harness whereby numerous accidents have been occasioned.

It has also happened that at times when persons have been strapped or attached to firemen in the above described manner that said persons during the excitement of fire and descent of a ladder cling to the ladder or impede firemens efiorts on their behalf, and the present invention aims to obviate said undesirable prior practice by providing an escape means assembled with a particular ladder construction whereby the combination may be used advantageously for rescuing people fro-m the upper fioors of burning buildings, the ladder of which may, at desired times be used in a conventional manner and solely for ladder purposes.

Referring now to the drawing for a more particular description it! indicates generally an elongated ladder having oppositely disposed side 'rails H and I2 secured together by means of transversely disposed spaced apart rung steps [3. As best shown in Figure 1, the lower ends of the side rails are spaced apart a greater distance than the upper ends thereof'whereby said rails converge towards each other from the lower wider end of the ladder toward its upper end. The ladder H] is of any selected 1ength,.sufiicient to extend from the ground indicated at fate and above the windows of one or more floors of a building.

The upper end of the ladder is provided with oppositely disposed arms 15 suitably secured to the top of the ladder, said arms being connected together by a transversely disposed strut 16, the latter being adapted to contact with the wall of a building for holding the upper end of the ladder a suitable distance away from said wall.

Between the rails H .and I2 and secured to the ladder by any suitable means, such as the U-bolts H, a guide track rail I8 is provided, said rail preferably being L-shaped in cross section and having at the lower end thereof a detent IQ for purposeslater described.

Adjacent the upper end of the ladder between and carried by the side rails II and i2 thereof a shaft 2!) is provided, said shaft being journalled in sockets 2!, the latter being oppositely disposed and carried bysaid rails. Medially disposed between said rails upon the shaft 29 a pulley wheel 22 is pivotally mounted.

A rope, cable or similar flexible strand 23 eX- tends over the pulley 22, one end thereof being provided with a hook 24 shown in dotted l'ines'in Figure 1, said hook being attached to an eye 24" secured to a later described escape car. The opposite end of the cable 23 is coiled around a winding-drum 25, the latter being horizontally disposed and axially secured to a shaft 26 which extends through said drum. One end of said shaft 26 is journalled in a socket 21, the latter being secured to the side rail I2 adjacent the lower end of the ladder. The other end of the shaft 26 is journalled through said side rail ll.

One end of the drum 25 is provided with a toothed wheel 28 rigidly and axially secured thereto. or to the shaft 26, the teeth of said wheel being adapted to engage with a detent dog 29 the latter being pivotally mounted as at 38 to the side rail l I and it will be understood that at times when said dog is in a raised position that the drum is then free from said dog and that at times when said dog is engaged with a tooth of the wheel 28 revoluble movements of the drum in one direction and corresponding movements of the cable 23 are prevented. 7

The outer end of the shaft 26 is provided with a crank 3| for revolving the drum 25 at times when said dog permits the same and it will be understood, for long ladders and heavy equipment that a worm gear'and an electric motor may also be employed for revolving the shaft 26 and said drum.

Between the crank 3| and the rail ll braking means are provided for further governing movements of the drum 25, cable 23 and said escape car, said means including a brake-drum 32 axially disposed about and rigidly secured to the shaft 26. A flexible brake band 33 extends about the perimeter of the brake drum 32 having an end which is attached as'at 34 to the rail H and a. free end 35 which is'pivotally attached as at 36 to a bell-crank-lever 31, the latter being pivotally mounted as at 38 onv the side rail l I.

An operator may place his hand or foot on the outer end of the bell-crank-lever 31 and apply pressure thereto for contracting the brake band 33 and causing the latter to snugly engage with the brake-drum 32 for governing movements of the winding-drum 25, cable 23 and said escape whereby said car is attached to the cables 23, 42 and 43 during use.

To the back wall 5i vertically spaced apart notched guide blocks 52 are secured, by any suitable means, which, as best illustrated by the dotted lines in Figure 1, receive within the notches thereof the guide track l8 whereby dur-- ing ascending and descending movements of the escape car the latter is prevented from transverse movements with respect to the ladder l0.

Also secured to said back wall, by any suitable means, and adjacent to the upper and lower ends of said car, four journal bolsters 53 are provided, being oppositely disposed and spaced apart in pairs.

Between and journalled through the lowermost pairs of bolsters 53 a shaft 54 is disposed and a similar shaft 55 is provided between and through the uppermost pairs of bolsters.

As shown in Figure 1, the escape car is wider than the Width of the ladder l8 and since the side rails of the ladder are convergent, elongated pairs of rollers 56 are oppositely disposed and pivotally mounted on the lower shaft 54. Similarly oppositely disposed elongated pairs of rollers 51 are provided on the upper shaft 55, said rollers being of sufficient length whereby some portions of the perimeters thereof bear against the side rails of the ladder In at all times during ascending and descending movements of the escape car, said elongation of the rollers being complemental to the convergence upwardly of said side rails for engagement with said side rails during said movements of the escape car.

The car is provided with a bottom 58, oppositely disposed side walls 59, a front wall 68, the lower portion of the latter being provided with a door 6| which, as best shown in Figure 1, is hingedly secured as at 62 to said car, said door being provided with a latch 63 and a notched latch-strike nals, the latter being secured to the oppositely disposed side rails H and I 2 for permitting rotary movements of the shaft 39.

Oppositely disposed pulleys 40 and 4| are keyed to the shaft 39 and flexible cables 42 and 43, respectively, extend over the pulleys 40 and 4|, the ends of said cables'each'being provided with a hook, the latter in use being engaged with complemental eyes '45. The eyes 45 are, as best shown in Figure 2, secured to the escape car by any suitable means. The other ends of the cables 42 and 43 are secured to rings 46.

A platform 41 isprovided preferably in the form of an iron slab whereby the mass and weight thereof serves to, counterbalance the Weight of the escape car. Opposit'e ends of the platform are attached to inverted V- shaped sling elements 48 and 49. the latter being respectively attached to the oppositely disposed rings as and to the cables 43 and 42, respectively.

The escape car is of rectangular oblong configuration being generally indicated at fiil, having a back wall 5! to the upper end of which the eyes 45 an 24 are secured by any suitable means Y or keeper 64.

The car further preferably includes a trans versely disposed partition platform 65 approximately midway between the upper and lower ends ,ing 66 which permits entrance to the lower compartment of the car through said opening.

The upper'end of the escape-car is provided with a cover 61, the latter being pivotally secured to said end by means of hinges 68.

Within the car a step-rung 69 is provided for facilitating entrance of occupants into the lower compartment thereof from said upper compartment and through the opening 66 of the platform 65.

Within the car and above the platform '65 oppositely disposed treadles 18 are provided, the latter being pivotally attached by means of suitable hinges or the like H to the platform 65. The free ends of the treadles 10 are each provided with a rod 12, the lower ends of which are pivotally attached as at 13 to said treadles, the

- upper ends of said rods being similarly pivot- Adjacent the hinges H and underneath eachtreadle 10 there is secured, by any suitable means, to each of said treadles a rod 15, said rods extending horizontally outwardly from said treadles and through elongated slots 16 provided through the side walls 59 of the car, said slots permitting said rods 15 to move upwardly and downwardly at times when the treadles are moved. The outer ends of each of the rods 15 are provided with reach-rods H, the lower ends of the latter being provided with eyes for pivotally attaching said reach rods to said rods 15, as best shown in Figure 2.

The upper ends of the reach rods 11 are similarly provided with eyes for a pivotal attachment to one of the arms of bell-crank-levers 18. The bell-crank-levers are connected together, as best illustrated by the dotted lines in Figure 1, whereby said cranks move in unison with respect to the reach rods 11 and treadles Ill at times when a weight is applied to either one of the treadles 10. The connection between the bellcranks consists of a crank-throw 19, the latter extending across the major portion of the upper end of the rear wall of the car and as thus described it will be understood that at times when a treadle H1 is moved downwardly that said crank throw I9 is thereby moved from the normal position thereof as shown in Figure 2 toward the guide-rail 8.

Adjacent the upper end of the side rails I I and I2 and pivotally attached as at 88 to the inner surfaces of said rails vertically swingable detents 8| are provided, said detents normally being urged outwardly by means of springs 82 carried by the upper portions of said rails as shown in Figure 2.

The outward movement of the detents 8| is limited by means of stop lugs 83 which contact with upper notched portions of said detents at times when the latter move sufliciently outward.

Secured to the rear wall 5| and closely adjacent to the upper end of said wall, a pair of oppositely disposed stationary detents 84 are provided which are in vertical alignment with the above described swingable detents 8| carried by the ladder whereby at times when the escape car is raised vertically sufiiciently said stationary detents 84 engage with the vertically disposed swingable detents 8| and press the latter towards their springs 82 and against the urge of said springs in a manner whereby at the time said stationary detents 84 become disposed above the swingable detents 8| the latter then become urged outwardly away from said ladder by their springs 82 and disposed at said time under the stationary detents 84 for detaining the escape car at the top of the ladder until it is released for descent.

At the time it is desired that the escape car 5|] be freed from the swingable detents 8| and for said purpose either one or both of the treadles I0 are actuated, said actuation causing the crank-throw 19 to be moved towards the ladder and against the swingable detents 8| for forcing the latter towards the ladder and against the urge of their springs 82 in a manner whereby said stationary detent 84 become freed from said swingable detents 8| for permitting the escape car to descend.

In operation at times when the ladder I8 is placed inclinedly and th upper end thereof is held away from th wall of a building by the arms I5 there is an appreciable space between the lower end of the ladder and said wall which permits the platform 41 to freely ascend correspondingly with respect to descending movements of the escape car. Assuming that the escape car has been raised by the above described means to the top of the ladder and that the swingable detents 8| are engaged with the Stationary detents 84, the cover 69 at said time being open, occupants enter said car and upon disengagement of said detents the car then is permitted to descend gradually or fast as occasion may require, said movement being governed by the brake means including the brake band 32 and when the car reaches the lower end of the guide track IS the detent I9 at said lower end engages with said car for preventing further downward movement thereof; whereupon the door BI is opened and egress of the occupants permitted. During said descending movement of the car additional firemen may be readily elevated by weight of said car and descending occupants, said firemen standing on the platform l5 for said purpose.

As thus described it will be understood that during loading of the escape car that in the event occupants of said car prematurely actuate either one or both of the trip treadles 10 thereby releasing the car for a descent that, at times when the firemen stationed at the bottom of the ladder do not desire said car to descend, said firemen may prevent the same by means of employing the braking bell-crank lever 31.

From the foregoing description it is thought to be obvious that an escape ladder constructed in accordance with my invention is particularly well adapted for use by reason of the convenience and facility with which it may be assembled and operated, and it will also be obvious that my invention is susceptible of some change and modification without departing from the principles and spirit thereof and for this reason I do not wish it to be understood as limiting myself to the precise arrangement and formation of the several parts herein shown in carrying out my invention in practice except as claimed.

I claim:

A fire escape apparatus comprising a ladder adapted to be leaned against an outer wall of a building, said ladder having side rails convergently disposed toward the top thereof, a guide track disposed between said side rails, a pulley at the upper end of said ladder, an escape car having guide blocks for sliding engagement with said guide rail, a winding drum at the lower end of said ladder, a cable disposed over said pulley having an end attached to said drum and an opposite end secured to said car for raising said car, an axle at each end of said car, an elongated roller at each end of each axle for engagement with said convergent side rails during sliding movements of said car, and means for governing th speed of a descent of said car along said ladder.

ISAIAH GRAHAM.

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