US2071813A - Moving stairway - Google Patents

Description

Feb. 23, 1937. E. M. BOUTON ET AL 2,071,313

' MOVING STAIRWAY Filed Jan. 11, 1935 INVENTORS WITNESSES:

E cigar M. Baufon a? BMW/M Patented Feb. 23, 1337 PNEENT OFFICE MOVING. STAIRWAY" Edgar M. Bouton, Chicago, Ill., and GeorgeC.

Saltzman, Edgewood,

Pa assignors to West'- inghouse Electric Elevator Company; Chicago, 111., a corporation of Illinois Application January 11, 1935,'Serial No. 1,282

2 Claims.

Our invention relates to moving stairways in which the steps are operated by endless gear chainsandmore particularly to means for operating the handrails usually associated with such stairways.

In constructing moving stairways, it is customary to provide movable flexible handrails and means for causing the handrails to travel with. the stairway steps, so that persons riding the stairway may grasp the handrail as they ascend or descend the stairs.

One object of our invention is to provide for so operating such handrails that they will always travel at substantially the same speed as the steps.

Another object is to provide means for automatically indicating to the attendants in charge of moving stairways when the operating mechanism for the handrails has reached such a 0 condition that it should receive attention and be adjusted for better operation.

It is also an object to provide a means for first giving such attendants a visible warning signal that the handrail needs adjustment and then giving them an audible warning signal if the handrail is not adjusted in response to the first warning signal.

Other objects of the invention will be apparent from the following description taken in conjunction with the accompanying drawing, in which Figure 1 is a skeleton-like view, in side elevation, taken from the interior of a moving stairway provided With a handrail constructed in accordance with our invention,

Fig. 2'is an enlarged view, in side elevation, looking from the interior of the stairway, of the means for operating the handrail included in Fig. 1, and

Fig. 3 is a view in cross section of the upper steps and the handrail tightening means of a moving stairway corresponding to the line IIIIII of Fig. 2.

Referring more particularly to the drawing, we have illustrated a moving stairway as comprising an endless series of movable steps I disposed to be moved along tracks by a pair of gear chains 3- between an upper landing 5 and a lower landing-6. The gear chains may be supported at the lower landing and at the upper landing by suitable sprocket wheels 1 and 8. Any suitable truss or frame (not shown) may be provided for supporting the moving steps between the upper landing and the lower landing. The upper sprocket wheels l may be driven in any suitable fifi manner as by a motor (not shown) connected to the shaft l0 upon which the wheels are mounted.

Each of the chains for operating the steps comprises a plurality of inner links M: (Fig. 2) and outer links [2 connected by pivot pins t3. A roller I4 is disposed upon each of the pivot pins to increase the ease of operation of the chains in passing over the sprocket wheels.

Each of the steps I (Fig. 3) comprises, a frame: l5 and a stair tread l6 mounted thereon. The front end ofthe frameis provided with an axle H, the outer ends of which extend through hol low pivot pins in the chain into position to be supported by leading rollers l8; operating'upon track rails it! while the stepis running upon the upper side ofthe stairway. The rear portion of the step frame is provided with a pair ofjournals 2!, in each of which is mounted a stubshaft 2;2

for atrailing roller 23. The trailing rollers run along track rail 2!! while the step moves along the upper side of the stairway.

The track rails l9 and 20 may be welded or otherwise secured to'a channel iron 24 supported upon an upwardly projecting portion of a bracket member 25. A suitable angle iron guardrail 213 may be mounted above each of the track rails ii! in a position to prevent the leading rollers fromleaving the tracks. With this construction, the steps will be moved along the tracks, by reason of their front axles extending through the gear chains in such manner that any movement imparted to the gear chains will be imparted to the steps. It will also be apparent that the gear chains and steps will be supported to a greater or less extent, while between the upper and lower terminals, by the step rollers following the tracks.

A suitable channel iron 21 is also mounted upon the bracket 25., a short distance beneath each of the gear chains for the purpose of pre-. venting the chains from sagging or' dropping beyond a predetermined distance.

As usual in moving stairways. a traveling handrail v30 isprovided at each side of the steps to move with the steps and at substantially the same speed as the steps. The handrail 3,0 at the right.- handside of the steps is mounted upon a newel wheel 3| (Fig. 1) at the lower landing and upon a pair of newel'wheels 32 and 33. at the upper landing. Aguide strip 34 (Fig. 2) is'provided-for supporting and guiding the handrail'between the upper and the lower landings.

Inasmuch'as'the handrail is longand flexible, it is necessaryto provide some means for keep: ing'it under'te'nsion at all times; In the present system this is accomplished looping the handrail over a reversing wheel 35 and a tightener wheel 36. The reversing wheel is mounted beside the newel wheel 32 and parallel therewith. The tightener wheel 36 is rotatably mounted upon a stub axle 3! at an angle to, and between, the newel wheel 32 and the reversing Wheel 35. The stub axle is carried by a movable carriage 38 supported by a pair of angle irons 39. The carriage is provided with grooves in its opposite sides to receive the inner edges of the angle irons, thus permitting the carriage to slide along the irons. The outer sides of the angle irons 39 are welded or otherwise secured to the flanges of a. channel iron 46 which, in turn, is mounted upon the main support (not shown) for the stairway. The movable carriage 38 and its supporting angle irons 39 are mounted parallel to the upper side of the stairway so that the carriage and its tightener wheel may move toward or away from the reversing wheel 35 in accordance with the tension on the handrail.

It is desirable to operate the handrail under a predetermined tension, therefore, the tightener wheel carriage 36 is provided with a rod 4| which extends away from the side of the carriage opposite the reversing wheel and passes freely through an aperture in a channel iron 42 which may be firmly affixed to the stairway frame (not shown) by welding or in any other suitable manner. The projecting end of the rod M is screw threaded to receive a cooperating threaded nut 43.

A compression spring 44 is concentrically disposed upon the rod between the outer side of the channel iron 42 and the nut 43. By adjusting the nut 43, the spring 44 may be compressed to exert a predetermined tension upon the carriage 38 and thereby cause the tightener wheel 36 to exert a corresponding tension upon the handrail 30 by expanding the loop in the handrail disposed over the tightener wheel and the reversing wheel. Hence, with this construction the handrail may be maintained at any desired tension by adjusting the nut 43.

Any suitable means may be provided for causing the handrail to move at the same speed as the movement of the steps. In the present system we have indicated a driving chain 46 (Fig. 2) passing over a sprocket wheel 41 attached to the newel wheel 33, thence over a sprocket wheel 48 attached to the newel wheel 32, and thence around a sprocket wheel 49 attached to the driven shaft l0. Consequently, when the shaft [6 is driven to operate the steps, the sprocket wheel 49 is driven .to operate the chain 46 over the driven sprocket wheels 4? and 48, thereby causing the newel wheels 32 and 33 to rotate for the purpose of moving the handrail in accordance with the movement of the steps.

In practice it is found that the handrails usually lengthen considerably in use. This causes the tightener wheel to move away from the reversing wheel and it ultimately reaches a point where the spring tension on the tightener wheel decreases to a point such that the handrail slips and does not move in synchronism with the movement of the steps. In view of the fact that the attendant of the stairway does not have to adjust the tightener wheel every day, it is usually forgotten and this condition is not discovered until it is observed that the handrail fails to move with the steps. This occurs when the friction between the handrail and the driven newel wheels becomes so low that the handrail slips or fails to move at all.

In practicing our invention we prevent a situa:

tion of this kind from arising by providing a means for giving the attendant a visible warning signal when the tightener wheels should be readjustedand an additional audible warning signal if the attendant does not respond to the Visible Warning means and the handrail tightener wheel slides still further toward the limit of its movement. The visible warning means comprises a pair of electric lamps 50 and 5| and the audible warning means comprises a pair of electrically operated buzzers or bells 52 and 53. The lamps and bells may. be mounted in any suitable location, but we prefer to mount one lamp and its associated bell in the engine or driving compartment which the attendant frequents in attending to the driving motor, etc. The other warning lamp 5| and its associated audible warning means 53 are preferably located at the lower terminal of the stairway where they may be seen and heard by any one associated with the operation of the building. The lamps 5i] and 5| are preferably red in color and are electrically connected in a circuit including a battery 54 or other suitable source of electric energy.

A normally open switch 55 mounted in a switch box 56 (Fig. 2) is provided for controlling the circuit. The switch box 56 is slidably disposed on a pair of supporting rails 6| mounted on the stairway frame (not shown). The position of the switch box may be adjusted by operating a pair of adjusting nuts 62 on a rod 63, the inner end of which is attached to the switch box and the outer end of which passes through a stop member 64. This adjusting means is provided so that the warning signal means may be set to operate at any predetermined position of the tightener wheel carriage.

The switch 55 is normally maintained in open position by a trigger handle 51 pivotally mounted in the upper part of the switch box. A projecting catch 58 is firmly affixed to the front portion of the carriage 38 in such position that when the stretching of the handrail permits the tightener wheel and its carriage to slide beyond a predetermined distance from the reversing wheel, the catch 58 strikes the upper portion of the trigger handle 5? and thereby permits the switch 55, which is biased to a closed position, to close its contact members and thereby complete a circuit for lighting the warning signal lamps 56 and 5|. The lighting of these lamps indicates to the attendant that the adjustment of the handrail and its tightener wheel need attention. After the attendant notes the lighting of a signal lamp, he may take the first favorable opportunity, as when the stairway is shut down at night, to shorten the handrail or he may adjust the nut 43 to increase the tension of the spring 44 and thereby cause the handrail to operate as usual without stopping the stairway.

If the nut 43 is adjusted, the switch box 56 should be moved forward by adjusting the nuts 62 on the rod 63 and the trigger lever 5'! should be restored to its upright position to hold the switch 55 open. After the switch box is moved forwardly to relocate the switch 56, the warning lamps will be lighted again when the handrail becomes so loose that it permits the tightener carriage to move toward its outer limit to again engage the trigger 51, thereby again warning the attendant of the necessity of adjusting the tension of the handrail. The lighting of the signal lamps 5| and 52 will also call attention to the fact that the tightener wheel has reached its limit of travel and that the handrail must be shortened and the mg.

tion of the carriage readjusted to secure the proper operation of the tensioning means.

If the attendant fails to respond to the signal given by the warning lamps, by adjusting the compression spring 44 by means of the compression screw 43 or by shortening the handrail, a further stretching of the handrail will permit the tightener wheel carriage to continue its outward movement to such an extent that the catch 58 will then engage the trigger handle of a switch 66, and move it to such an extent as to permit the switch 66 to close and thereby complete a circuit for energizing the signal bells 52 and 53. Inasmuch as the signal bells 52 and 53 will be heard over the section of the building at the foot of the stairway and also by any one entering the driving motor compartment, the attendants will be constrained by the continued noise to the necessary adjustment of the handrail or the tensioning means and prevent the handrail leaving the newel wheels and guides on which it is mounted.

It is to be understood that when the handrail tension is adjusted and the position of the switch box 56 is readjusted, the distance between the catch 58 and the trigger 5'! represents apermissible stretch in the handrail to a point where an adjustment must be made as soon as practicable without stopping the stairway. The moving stairway may still be operated with safety to passengers until the handrail stretches to an extent to cause the trigger 65 to be engaged, thereby operating the audible signals. At this point adjustment of the spring is imperative and a stretch much beyond this point may cause the handrail to leave its driving wheels with resultant danger to the passengers. When the audible signal is energized, therefore, the stairway should be stopped to make the required adjustments, but such stopping should not occur until the stairway has been cleared of passengers in order to avoid the confusion and danger of suddenly stopping it while loaded.

By the foregoing means, it will be seen that we have provided for indicating to the attendants of a stairway when the handrail should be adjusted for tension before it reaches an unworkable condition and also for warning the attendants when the tensioning means has closely approached the limit of its operation, thereby permitting repairs and adjustment to be made at convenient periods before the tensioning means ceases its operation.

It will also be seen that our improvement provides for taking care of such adjustment of the handrail as may be necessary without waiting until the apparatus suddenly stops while the stairway is in passenger carrying operation and that it thereby avoids possible injuries which might occur to the passengers from such sudden stopping.

Although we have illustrated and described only one specific embodiment of our invention, it is to be understood that many changes and modifications may be made therein without departing from the spirit and scope of the invention.

We claim as our invention:

1. In a moving stairway having a plurality of movable steps, a plurality of newel wheels, an endless flexible handrail disposed on the newel wheels for operation in accordance with the movement of the steps, a device for applying a predetermined tension to the handrail to maintain it in a taut condition over the newel wheels, a signal device, a circuit for connecting the signal device to a source of electrical energy, a switch for controlling said circuit, means responsive to a predetermined decrease in such tension, prior to the time when the tension device should be readjusted, for closing the switch to energize the signal device for indicating that the tensioning device requires adjustment, and means for readjusting the position of the switch afterthe tension device has been adjusted whereby a further decrease in the tension will again operate the switch to energize the signal device to indicate that the tension de- ,vice again needs adjustment.

2. In a moving stairway having a plurality of movable steps, a plurality of newel wheels, an endless flexible handrail disposed on the newel wheels for operation in accordance with the operation of the steps, a tightener wheel disposed in engagement with the handrail, a movable carriage for supporting the tightener wheel, a spring for applying a predetermined tension on the tightener wheel carriage to cause the tightener wheel to effect a tensioning action against the handrail, means for adjusting the tension of the spring, a signal device, a circuit for connectng the signal device to a source of energy, a switch for controlling the circuit, means responsive to movement of the tightener wheel carriage, prior tothe time when the tension of the spring should be readjusted, for operating the switch to energize the signal device for giving a warning indicating that the adjustment of the spring requires attention, and means for readjusting the position of the switch after the spring has been adjusted whereby a further predetermined movement of the tightener carriage will again operate the switch to energize the signal device to indicate that the spring again needs adjustment.

' EDGAR M. BOUTON.

GEORGE C. SALTZMAN.

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