Skirt panel for a passenger conveyor

Information

  • Patent Grant
  • 6257390
  • Patent Number
    6,257,390
  • Date Filed
    Wednesday, October 27, 1999
    25 years ago
  • Date Issued
    Tuesday, July 10, 2001
    23 years ago
  • Inventors
  • Examiners
    • Bidwell; James R.
    Agents
    • Ohlandt, Greeley, Ruggiero & Perle, LLC
    • Rauchfuss; George W.
Abstract
A skirt panel for a passenger conveyor, particularly an escalator having a plurality of steps. The skirt panel has a plurality of ball bearings that protrude enough from its surface to give a sliding and/or deflecting action to traveling objects so as to reduce skirt panel surface friction and to minimize side of step entrapments. The skirt panel can be fitted for installation as a skirt panel or as an overlay to an already installed skirt panel.
Description




FIELD OF INVENTION




This invention relates to passenger conveyors and, in particular, to a skirt panel for passenger conveyors.




BACKGROUND OF INVENTION




Passenger conveyors such as escalators and moving walks typically have a frame that supports a passenger moving portion upon which passengers are situated and a drive for causing the moving portion to travel along the frame. The moving portion has a series of steps for the case of an escalator and a flat platform for the case of a moving walk. A pair of balustrades having handrails, skirt panels and balustrade panels is attached to the frame and is substantially vertically disposed on either side of the moving portion.




The skirt panel extends along and adjacent the moving portion, for example escalator steps, and extends vertically upward from the treads of the steps. The skirt panel is generally stationary while the escalator steps are in motion. The skirt panel and moving escalator steps are separated by a skirt/step gap that is usually {fraction (1/16)} inch or more, but may be smaller.




Passenger injuries have occurred by entrapment in the skirt/step gap of objects such as body parts, clothing or accessories. Body parts that have been entrapped include limbs, fingers, feet, toes, hair and the like. Clothing that has been entrapped includes shoes, shoe laces, draw strings, scarves and the like. Accessories that have been entrapped include pocket books, book bags, back packs and the like.




Entrapment occurs as a result of the moving object coming in contact with the stationary skirt panel, being slowed or stopped by the frictional force of the contact and then being forced into the skirt/step gap as the escalator steps continue to move. Entrapment can occur at any point along the skirt/step gap. Any point where entrapment occurs, is known as the pinch point. For example, one point of the skirt/step gap where many entrapments occur is the juncture of the tread of one step and the riser of the next step. Some known skirt panels have deflected away from the moving steps upon heavy contact so that the skirt/step gap and pinch point becomes enlarged, thereby enhancing the chance of an entrapment




The entrapment problem has been addressed in several ways. U.S. Pat. No. 5,695,040 discloses an escalator that has a brush or a wiper disposed in the skirt/step gap as a blocking member. Both the brush and the wiper are flexible so that objects that enter the skirt/step gap are still subject to seizure and entrapment.




A side-of-step entrapment product, available under the SafetyStrip™ trademark from Adams Elevator Company of Niles, Ill. is a continuous brush that is installed along the length of the skirt panel. The brush is supposed to warn passengers of impending danger when they or their clothing contact it and to present a barrier that must be penetrated to reach the skirt/step gap. This may work for some passengers, but not all. There are some passengers whose limbs (for example, their feet) will miss the brush and contact the skirt panel and be forced into the skirt/step gap. Other passengers will bump hard into the brush, penetrate the brush barrier and contact the skirt panel so as to be exposed to entrapment in the skirt/step gap. Some items of clothing may miss the brush and become entrapped. Other items of clothing that contact the brush may still contact the skirt panel and become entrapped.




Another technique has been to coat the skirt panel with a low friction material having a low coefficient of friction (lower than that of stainless steel). However, the materials used have not reduced friction enough to overcome the entrapment problem.




An escalator step guidance system, available under the SureGuide™ trademark from Schindler Elevator Corp. of Morristown, N.J. reduces the skirt/step gap size by means of a screw and wiper pad assembly that is mounted below each step tread. Whether the skirt/step gap is {fraction (1/16)} inch, larger or smaller, there is a skirt/step gap in which objects may be entrapped.




SUMMARY OF INVENTION




An object of the present invention is to provide a new and improved skirt panel for a passenger conveyor.




Another object of the present invention is to provide a skirt panel having a surface that causes a moving object to move or slide along the surface and, thus, reduce the effective friction of the surface.




Still another object of the present invention is to provide a skirt panel that deflects, bumps or pushes a moving object away from the panel surface.




Yet another object of the present invention is to provide a skirt panel that presents a low friction moveable surface to moving objects.




The foregoing and other objects are provided in the present invention by a skirt panel having a structure that has a surface facing the moving portion of a passenger conveyor. For the case of an escalator, the moving portion is the escalator steps. One or more moveable elements is mounted in the surface of the skirt panel so as to provide a low friction moveable surface to moving objects.




In a preferred embodiments the moveable elements are bearings mounted in the structure so that a portion of each bearing protrudes outwardly from the skirt panel surface so as to provide a sliding action for objects that contact the bearings as the steps travel.




The bearings are mounted in holders within the structure. The holders hold the bearings in place and allow the bearings to provide the sliding action. In some preferred embodiments of the present invention, the bearings are ball bearings.




The bearings are scattered about the skirt panel surface in an array and are spaced close enough to provide the sliding action and a reduction in surface friction. In some preferred embodiments of the present invention, the array is a honeycomb pattern.




In one preferred embodiment of the present invention, the structure includes a first layer whose front surface is the skirt panel surface. This layer has a plurality of apertures through which the bearings protrude. The structure also has a second layer that contains the bearing holders. The second layer is disposed behind the first layer with the bearing holders in registry with the apertures of the first layer.




In a preferred embodiment of the present invention, each bearing holder is a cavity that extends through the second layer. A third layer of the structure is disposed behind the second layer for retaining the bearings within the cavities.











BRIEF DESCRIPTION OF DRAWINGS




Other and further objects, advantages and features of the present invention will be understood by reference to the following specification in conjunction with the accompanying drawings, in which like reference characters denote like elements of structure and:





FIG. 1

is a perspective view of a portion of an escalator;





FIG. 2

is a perspective view of a skirt panel in accordance with one preferred embodiment of the present invention;





FIG. 3

is a top view of a first layer of the skirt panel of

FIG. 2

;





FIG. 4

is an elevational view of the first layer of

FIG. 3

;





FIG. 5

is a top view of a second layer of the skirt panel of

FIG. 2

;





FIG. 6

is a cross section view along the lines


6





6


of

FIG. 5

;





FIG. 7

is a perspective view of another skirt panel embodiment of the present invention;





FIG. 8

is a top view of the bearing and plug assembly of

FIG. 7

;





FIG. 9

is a cross sectional view of

FIG. 7

;





FIG. 10

is a cross sectional view of another skirt panel embodiment of the present invention;





FIG. 11

is a cross sectional view of yet another skirt panel embodiment of the present invention; and





FIG. 12

is a cross sectional view of a further skirt panel embodiment of the present invention.











DESCRIPTION OF PREFERRED EMBODIMENTS




The skirt panel of the present invention is useful in passenger conveyors of all types. However, by way of example and completeness of description, the skirt panel of the present invention will be described herein for escalator type passenger conveyors.




Referring to

FIG. 1

, an escalator


20


is generally represented by numeral


20


. Escalator


20


has a frame


21


, a drive (not shown), a pair of balustrades


22


and a plurality of steps


23


. Each balustrade


22


has a handrail


24


, a balustrade panel


25


and a skirt panel


26


. At the interface of skirt panel


26


and steps


23


is a skirt/step gap that for many current designs is typically about {fraction (1/16)} inch, but may be smaller or larger.




Steps


23


are driven by the drive in a generally circuitous path in either the up or down direction. Balustrade panels


22


and skirt panels


26


remain stationary as the steps move. Passenger injuries have occurred by entrapment in the aforementioned skirt/step gap of objects such as body parts, clothing or accessories. The entrapment occurs as a result of the moving object coming in contact with stationary skirt panel


26


, being slowed or stopped by the frictional force of the contact and then being forced into the skirt/step gap as escalator steps


23


continue to move.




With reference to

FIGS. 2 through 6

, there is provided a skirt panel generally represented by numeral


36


according to a preferred embodiment of the present invention. Skirt panel


36


has a structure generally represented by numeral


37


. Structure


37


has first, second, third and fourth layers


38


,


39


,


40


and


41


, respectively. First, second, third and fourth layers


38


,


39


,


40


and


41


are held together in a sandwich fashion by means of any suitable fastening technique as, for example, by bolts


42


that extend downwardly from first layer


38


through layers


39


,


40


and


41


. The sandwich structure


37


is secured by nuts (not shown) applied to the screw thread portions of bolts


42


.




Structure


37


contains a plurality of moveable elements


43


that provide a low friction moving surface for moving objects that contact any of the moveable elements. Although the moveable elements may be any moveable parts such as belts, rotatable cylinders, disks, plates, panels, balls and the like, the moveable elements are preferably bearings that protrude above or are flush with the top surface


44


of first layer


38


. The bearing protrusions are small enough to fit within the skirt/step gap or can contact the steps. Bearings


43


have one or more directions of rotation and in preferred embodiments are ball bearings that have an infinite number of directions of rotation.




Bearings


43


are scattered about top surface


44


in an array that in preferred embodiments is a honeycomb pattern. The spacing of bearings


43


in the array is close enough to impart a sliding and/or deflecting action to moving objects that contact top surface


44


as escalator steps


23


travel by skirt panel


36


so as to provide an effective reduction of surface friction. When such contact is made with bearings


43


, body parts, clothing accessories or other objects can be pulled away with ease and without panic by sliding or deflecting them away and, thus, eliminating frictional force effect, thereby reducing the risk of entrapment. This action also causes a sensation, making a passenger aware of contact with skirt panel


36


that serves as a warning to pull away the object that has made contact. The protruding ball bearings


43


have the effect of reducing the size of the skirt/step gap by the amount of the protrusions of the ball bearings.




First layer


38


contains a plurality of apertures


45


through which bearings


43


protrude. Structure


37


contains a plurality of bearing holders


46


arranged in registry with apertures


45


of first layer


38


. Bearing holders


46


are formed by cavities


47


that extend through second layer


39


. Bearings


43


reside in respective cavities


47


bounded at the bottom by third layer


40


. Third layer


40


has a low coefficient friction so as to provide a smooth low friction surface for bearings


43


. Each cavity


47


has a rim portion


48


that is shaped to closely match the bearing contour and dimensioned so as to minimize entry of contaminants into cavities


47


that can cause interference with bearing providing the moving or sliding action. Each rim portion


48


is an annulus that extends upwardly into a corresponding aperture


45


of first layer


38


.




Skirt panel


36


is preferably made in modular sections that can be fit together to form an entire skirt panel


26


when installed on an escalator. Alternatively, sections of skirt panels


36


can also be disposed in specific problem areas where contact with moving objects is expected. Skirt panel


36


can be dimensioned to fit over the front or back of an existing skirt panel


26


by means of bolts or other fastening techniques such that the bearing surface is the skirt panel surface.




The materials for first, second, third and fourth layers


38


,


39


,


40


and


41


are selected to give strength to skirt panel


36


so that it does not deflect away from the steps and widen the skirt/step gap upon contact with an object and to give low coefficient of friction surfaces for bearings


43


. In one embodiment, first and fourth layers


38


and


41


are stainless steel, second layer


39


is an acetyl plastic available under the DELRIN® trademark from A. L. Hyde Company of Grenloch, N.J. and third layer is a plastic available under model UHMW from A. L. Hyde Company.




Bearings


43


can be made of any low friction coefficient and durable material such as steel, ceramic or plastic. In the aforementioned embodiment, bearings


43


are stainless steel ball bearings.




In some embodiments, the bearings, when spinning and contacting the plastic second and third layers, can emit an audible noise which alerts the passenger to avoid entrapment.




Provision can be made for lubricating bearings


43


as, for example, by use of a lubricant impregnated plastic for layers


39


and/or


40


or by use of a lubricating port and channel system (not shown in

FIGS. 1 through 6

) in structure


37


.





FIGS. 7 through 12

show another group of embodiments of the present invention that employ bearing assemblies in the form of plugs that can be plugged into holes closely spaced about a skirt panel either entirely or just in expected problem areas. The plugs can be installed one by one in an installed skirt panel or can be installed in a separate skirt panel section or module that can be placed over the front or back of or replace an installed skirt panel. The protrusions of the ball bearings is low enough to fit in the skirt/step gap. This enables the step sides to pass and even contact the bearings, leaving little or no clearance in the skirt/step gap.




In

FIGS. 7 through 10

, a bearing assembly is generally designated by numeral


60


. Bearing assembly


60


has a plug


61


that is plugged into an aperture


65


in a skirt panel


66


. Plug


61


has a body


62


of durable material such as stainless steel or plastic. In the illustrated embodiments, body


62


is stainless steel and has a cylindrical shape with screw threads


59


. Body


62


contains a plastic bearing holder


63


for bearing


43


. The region


64


is open and contains air.




A rim


67


fits within the cylindrical top of body


62


. Rim


67


is designed to the contour of bearing


43


to minimize entry of contaminants into body


62


. Rim


67


has holes


68


that serve as grab holes for plug tightening into the skirt panel as well as lube ports for lubricating bearing


43


.




In

FIG. 10

, plug


61


also has a guard ring


69


that serves as a barrier to entry into bearing holder


63


of debris such as dirt, lint and the like. Bearing holder


63


is constructed of two pieces so as to occupy substantially all of the space within plug body


62


.





FIGS. 11 and 12

show another plug type embodiment that has a cylindrical body


72


that has disposed in its bottom


74


an aperture


75


. Body


72


contains a bearing holder


73


for bearing


43


. A portion of bearing


43


extends through aperture


75


. Aperture


75


serves as an exit for debris and allows bearing


43


to roll freely.




In

FIG. 12

, rim


67


has separate lube ports


70


connecting to lube channels


71


that provide lubrication to bearing


43


in body


72


In one design, the channels


71


surround bearing


43


.




Although not illustrated, another plug embodiment of the present invention includes a bearing holder structure of the type shown in

FIGS. 2

through


6


where the bearing holder is bounded on the bottom by a body with a smooth plastic surface, such as the aforementioned model UHMW.




The present invention having been thus described with particular reference to the preferred forms thereof, it will be obvious that various changes and modifications may be made therein without departing from the spirit and scope of the present invention as defined in the appended claims.



Claims
  • 1. An escalator skirt panel having a surface that faces the traveling steps of an escalator, said escalator skirt panel comprising:a structure that includes said surface; a plurality of bearings; and means for mounting said bearings in said structure so that a portion of each said bearing protrudes outwardly from said surface so as to provide a sliding action for objects that contact said bearings as said steps travel.
  • 2. The invention according to claim 1 wherein said means for mounting comprises:a plurality of bearing holders that hold said bearings in place and allow said bearings to provide said sliding action.
  • 3. The invention according to claim 2 wherein said structure further comprises:a first layer having said surface as a front surface and a back surface, said front surface having a like plurality of apertures through which said bearings protrude.
  • 4. The invention according to claim 3 wherein said structure further comprises:a second layer having a front surface containing said bearing holders and situated with respect to said back surface of said first layer so that said bearing holders are in registry with said apertures.
  • 5. The invention according to claim 4 wherein said structure further comprises:said second layer having a back surface; each said bearing holder comprises a cavity that extends through said second layer between said front and back surfaces thereof; and a third layer for retaining and providing a smooth low coefficient of friction surface for said bearings within said cavities.
  • 6. The invention according to claim 5 where said bearings are ball bearings.
  • 7. The invention according to claim 6 wherein said plurality of bearings are situated in an array scattered about said surface.
  • 8. The invention according to claim 7 wherein said array is a honeycomb pattern.
  • 9. The invention according to claim 8 wherein each said bearing holder comprises:a rim portion extending over a portion of said bearing contained therein to minimize entry of contaminants into the bearing holder.
  • 10. The invention according to claim 9 and further comprising:means for holding said layers together.
  • 11. The invention according to claim 10 wherein the first, second and third layers have low enough coefficients of friction to allow said bearings to move.
  • 12. The invention according to claim 11 wherein said first layer is metal, and said second and third layers are plastic.
  • 13. The invention according to claim 1 wherein said plurality of bearings is situated in an array scattered about said surface.
  • 14. The invention according to claim 13 wherein said array is a honeycomb pattern.
  • 15. The invention according to claim 14 wherein said bearings are ball bearings.
  • 16. The invention according to claim 2 wherein each said bearing holder comprises:a rim portion extending over a portion of said bearing contained therein to minimize entry of contaminants into said bearing holder that would interfere with said bearing providing said sliding action.
  • 17. The invention according to claim 2 and further comprising: means for facilitating removal of contaminants from said bearing holders.
  • 18. The invention according to claim 2 wherein at least one of said bearing holders comprises:a plug having a cavity for holding one of said bearings.
  • 19. The invention according to claim 18 wherein said plug contains at least one lubricating port.
  • 20. The invention according to claim 19 wherein said cavity is an open cavity.
  • 21. A skirt panel having a surface that faces the traveling portion of a passenger conveyor, said skirt panel comprising:a structure that includes said surface; a plurality of bearings; and means for mounting said bearings in said structure so that a portion of each said bearing protrudes outwardly from said surface so as to provide a sliding action for objects that contact said bearings.
  • 22. The invention according to claim 21 wherein said means for mounting comprises:a plurality of bearing holders that hold said bearings in place and allow said bearings to provide said sliding action.
  • 23. The invention according to claim 22 wherein said structure further comprises:a first layer having said surface as a front surface and a back surface, said front surface having a like plurality of apertures through which said bearings protrude.
  • 24. The invention according to claim 23 wherein said structure further comprises:a second layer having a front surface containing said bearing holders and situated with respect to said back surface of said first layer so that said bearing holders are in registry with said apertures.
  • 25. The invention according to claim 24 wherein said structure further comprises:said second layer having a back surface; each said bearing holder comprises a cavity that extends through said second layer between said front and back surfaces thereof; and a third layer for retaining and providing a smooth low coefficient of friction surface for said bearings within said cavities.
  • 26. The invention according to claim 25 where said bearings are ball bearings.
  • 27. The invention according to claim 26 wherein said plurality of bearings are situated in an array scattered about said surface.
  • 28. The invention according to claim 27 wherein said array is a honeycomb pattern.
  • 29. The invention according to claim 28 wherein each said bearing holder comprises:a rim portion extending over a portion of said bearing contained therein to minimize entry of contaminants into the bearing holder that would interfere with said bearing providing said sliding action.
  • 30. The invention according to claim 29 and further comprising:means for holding said layers together.
  • 31. The invention according to claim 30 wherein the first, second and third layers have low enough coefficients of friction to allow said bearings to move.
  • 32. The invention according to claim 31 wherein said first layer is metal, and said second and third layers are plastic.
  • 33. A skirt panel having a surface that faces the traveling portion of a passenger conveyor, said skirt panel comprising:a structure that includes said surface; at least one moveable element; and means for mounting said moveable element in said structure so as to provide a low friction moveable surface for objects that contact said moveable element.
  • 34. A skirt panel in accordance with claim 33 wherein said moveable element is one of a plurality of moveable elements; andsaid objects travel with said traveling portion.
  • 35. A skirt panel in accordance with claim 34 wherein said means for mounting includes a plurality of holders to hold said moveable elements in place and allow said moveable elements to provide said low friction moveable surface to said objects that contact any of said moveable elements.
  • 36. A skirt panel in accordance with claim 35 wherein said structure further comprises:a first layer having said surface as a front surface and a back surface, said front surface having a like plurality of apertures through which said moveable elements protrude.
PCT Information
Filing Document Filing Date Country Kind 102e Date 371c Date
PCT/US98/09642 WO 00 10/27/1999 10/27/1999
Publishing Document Publishing Date Country Kind
WO98/51594 11/19/1998 WO A
US Referenced Citations (3)
Number Name Date Kind
3144118 Fabula Aug 1964
3799060 Johnson Mar 1974
5810147 Vanmoor Sep 1998
Foreign Referenced Citations (1)
Number Date Country
2556321 Jun 1977 DE