Escalator Defective Roller Detector

1. Field of Invention

The present invention relates in general to testing equipment and more specifically to a portable device for the correct testing and marking of escalator step height variations.

2. Discussion of Prior Art

In the field of escalators, an escalator which has good step rollers, good rack axle rollers, and good rack axle hubs, there is no discernable variance of vertical height from the leading edge to the trailing edge of one step to the next. However, in an instance where an escalator step roller has lost diameter surface area, from approximately 1/16" to a maximum of the radius of a roller, improper operation may occur. The danger represented by a bad roller is very clear when considering the meshing of an escalator step with the comb finger sections is dependant on the proper diameter of escalator step rollers and rack axle rollers or rollers related to insuring proper step height at comb area.

The patent to Bartman (U.S. Pat. No. 5,236,075) discloses an escalator broken roller detector 10. The device utilizes proximity sensors 18, 20 in order to detect the diameter of each roller 22. The sensors 18, 20 emit a symmetrical signal which, when interrupted due to a roller 22 falling off its spool 32, will automatically trigger an alarm 38 and an escalator stop switch 40. See FIGS. 1, 2 and col. 2, lines 6-53.

The patent to Wente et al. (U.S. Pat. No. 5,096,040) discloses a device for detecting missing steps in an escalator. The system comprises a detector 12 having a pair of rollers 16 mounted on a carriage 20 that engage a side 28 of the steps 6. The carriage 20 is biased by a spring 42 such that if a step 6 is missing, the carriage 20 moves toward the steps 6 which in turn moves the switch button 34 thus shutting off the power to the escalator. See FIGS. 1, 2 and ABSTRACT.

The patent to Zaharia et al. (U.S. Pat. No. 5,316,121) discloses a system for detecting missing steps utilizing a proximity sensor 26. The system will cause the escalator to stop if the sensor 26 detects a missing or misaligned step 14, 16 by cutting off power to the motor 38 and activating the brake 40. See col. 2, lines 60+.

The patent to Nurnberg et al. (U.S. Pat. No. 5,255,771) disclose a complete safety device 34 that is mounted directly onto the combplate frame 40. See FIG. 2.

In today's escalator maintenance field, defective escalator rollers are typically found in one of the following ways. A maintenance mechanic may provide power to the escalator and walk the escalator, either at the landing (flat) area and step between the leading edge and trailing edge of two consecutive steps on the ball of his or her foot while attempting to "feel" differences in vertical distances as small as 1/16". Generally, this method is unreliable and physically tiring. Another method is to barricade the top and bottom of an escalator and open the top or bottom floor plate and visually inspect each of the rollers. However, unless a mechanic were to put a caliper on each roller, they will most likely not notice a roller which has lost 1/8" of diameter surface area. Most mechanics generally look for "flat" spots on rollers caused by roller bearing defects, which cause the wheel to drag thereby causing excessive wear to the roller. Both of the above described ways of detecting rollers are laborious, time consuming, and unreliable.

Each of the above methods fails to provide a low cost, portable device which will provide an immediate indication to a service repairman of not only that an roller and/or height error exists with one of the steps, but also exactly which step(s) has produced the error.

The present invention can be attached to an escalator in minutes, is totally self contained, can be attached to the escalators of various manufacturers and is effective in detecting bad step and axle rollers with a loss of 1/16" of diameter surface area or more. The device can further mark the step in question and do all this in a fraction of the time of conventional methods.

The present invention is a device which is attached to the combfinger section of one side, right or left, of an escalator and extends onto the moving steps of the escalator. The device, once attached, gauges vertical differences from one step to another. On detecting a low escalator step the present invention emits an audible tone, actuates a light and marks the low spot on the step in question. The low spot on the step in question will, by location of the mark left on the step, indicate a bad escalator step roller, a rack axle roller, and in instances where the present invention is adjusted to extreme sensitivity may detect bad rack axle hubs. The small thin mark, its intensity indicating the extent of error, will wear off the step during normal traffic use in a relatively short time period or could be wiped off after repair is made.

FIG. 1 illustrates a perspective view of the present invention.

FIG. 2 illustrates a side view of the present invention.

FIG. 3 illustrates a top view of the present invention.

FIG. 4 illustrates the present invention marking a selected escalator step.

FIG. 1 shows the main body 1 which is a long rectangular beam. The main body 1 is attached to a stationary pedestal 3 by pivot pin 14. The stationary pedestal 3 is attached to platform 11, and the combfinger thru-bolt plate 4. The main body 1 is a pivoting boom which rides the step surfaces by attachment of the step surface rollers 9 and axle pedestal 2 by bolt 15. Tensioner springs 16 are attached to the platform 11 by the main body spring retainer 12. A spray actuating pedestal 5 is attached to the platform by a 3/8".times.1" bolt and lock washer (not shown). Spray actuating arm 7 is attached to the main body 1 with a 8/32".times.11/4" allen bolt (not shown). The spray linkage arm 6 is then attached to spray actuating pedestal 5 and spray actuating arm 7 by pivot pins and cotter pins 18 & 21. A spray can saddle 8 and paint can load device bracket 10 are attached to main body 1 with (1/4.times.1/4" steel rivets). The paint can load device 19 is attached to bracket 10. A spray adjustment screw 20 is screwed into spray actuating arm 7 through a 10/32" threaded hole. Sensor adjustment screw 13 is attached to platform 11 by screwing into a 8/32".times.5/16" tapped hole (not shown) in the platform.

In operation the device operates as follows:

First, remove bolts/screws from the combfinger section nearest to skirt pane (side) of escalator to be tested. Next, a visual and/or manual inspection of the closest step to the escalators platform should be performed to accurately calibrate the testing unit. A first step should be chosen that is within a 1/16" error in vertical height displacement then position this step under the wheels 9. With bolts provided and combfinger section still in place, the testing device is attached to one side of an escalator, through combfinger thru-bolt plate 4. Defective roller sensory device 22, which provides audible and visual indications, is actuated to monitor the testing procedure. The microswitch connection of element 22 (17) is mounted inside element 1 and actuated by element 13 upon 1 moving downward. Sensor adjustment screw 13 is adjusted upwards toward the underside of the main body 1 until a light emitting diode is activated and a tone sounds from defective roller sensory device 22. Then the sensor adjustment screw 13 is reversed using knob 26 until the light goes out and the tone stops sounding then the sensor locking wing nut 29 is secured. A spray can 24 (FIG. 4) is installed in the spray can saddle 8 with its nozzle tube 27 pointed downwardly through a hole (not shown) in the main body 1. The can is inserted and secured by pulling back on the knob 23 provided on the paint can load device 19 and released against the can of spray paint. Then, with paper or rag under spray tube, the user adjusts the spray adjustment screw 20 until spray begins, then reverses the screw 20 until spray stops and then locks wing nut 25. Now the escalator may be started. Please note that the stair unit should always be run in an up direction when the test unit is mounted at the bottom of the escalator. When the escalator is running and a low spot is detected, the device will sound tone and/or light indicators on the defective roller sensory device 22 and make a spray mark (FIG. 4) on the low spot of the step by vertical displacement of wheel 9 actuating a mechanical coupling of elements as follows: element 1 will pivot downward through elements 14 and 3; element 11, being a stable non-moving platform creates a geometrical coupling of elements 7 and 6 and 5 to then cause the spray actuator 20 to press on spray can nozzel and spray from the can 24 paint downwardly directed through the nozzle 27 creating mark 28.

A system and method has been shown in the above embodiments for the effective implementation of a portable device for the testing and recording of errors of vertical height or depth found in steps of escalators. While various preferred embodiments have been shown and described, it will be understood that there is no intent to limit the invention by such disclosure, but rather, is intended to cover all modifications and alternate constructions falling within the spirit and scope of the invention as defined in the appended claims.

The testing unit of the present invention may be used with any combination of the audible, visual and/or marking indicators or equivalents thereof to indicate a repair is needed. In addition the device may be used to test either side of a perspective escalator or may be modified, within the spirit of the specification, to simultaneously test both sides.

The device should not be limited by materials composition, size and/or specific connection details. The device could further use known equivalent motion detection system, attachment methods and/or marking methods without departing from the spirit and scope of the present invention. The device could be permanently built in to the escalator system itself.

The device should not be limited to the escalator art but could be used to test any equivalent structures (e.g. people movers, conveyor belts and the like.).