GB2235428A - Variable-angle escalator - Google Patents

Abstract

An escalator which is devised to operate within a range of different angles of inclination has a number of separate step members (1) upon the upper surface (2) of which a user of the escalator may stand. At at least one end of each step member a pair of guide wheels or rollers (4, 5) are mounted, the pairs of wheels or rollers on the different step members being spaced apart by a common vertical distance. The wheels or rollers engage a pair of parallel guide tracks (6, 9) which are spaced apart by that common vertical distance and a drive means (12) causes a corresponding wheel or roller in each pair to move along one of the tracks. The guide tracks are pivoted about a pair of vertically-aligned parallel pivots (15, 16) and are linked together so that they remain mutually parallel and spaced apart by a constant vertical distance as they pivot. The escalator may be mounted on a mobile carriage. <IMAGE>

Description

Variable-Angle Escalator The present invention is an escalator of which the angle of inclination can be varied. Such an escalator is of value in providing access between two locations of which the relative vertical height may change, or for affording access between different pairs of positions.

Thus, for example, access for passengers to a ship's deck from the quayside is conventionally provided by an accorrinadation ladder pivoted, for example, at the deck and resting with its other end upon the adjacent quayside. Relative vertical movement of the ship and shore is oompensated by rttveeent of the ladder about its pivot. As the angle of the ladder changes during pivoting, the individual steps of the ladder are maintained horizontal by means of one or more parallel-notion linkages.

Since the vertical distance from deck level to shore level may be substantial and passengers are of different degrees of agility or mobility, it would be highly desirable to provide an escalator instead of the conventional accommodation ladder. However the problem of maintaining the individual steps in a horizontal position, which is readily solved in the case of a pivotally- mounted ladder, becores much mDre difficult when applied to a variable-angle escalator.

An attempt to solve this problem is described in sited States Patent Specification No. 3834514, wherein an escalator is illustrated in which each step is of crescent-shaped crosssection. That is, as the angle of orientation of each step changes, a different portion of its craved surface is presented to the pedestrian user. Etwever the result is that the user trust always stand upon a curved surface rather than a flat step, which may leave an uncertain user with an imagined or actual lack of security and/or stability.

It is therefore an object of the present invention to provide an improved escalator, of which the angle of use may be varied and in which the steps remain level throughout the range of its available angles of use.

The escalator according to the present invention comprises a number of separate step IrEèrs each having an upper surface to support at least a part of the foot of a user of the escalator, a pair of guide wheels or rollers mounted upon at least one end of each step merrbet, the wheels or rollers of each pair being spaced apart by a common predetermined vertical distance, at least two parallel guide tracks, spaced apart vertically by said cortrrcn distance, and drive means to cause a corresponding wheel or roller in each of said pairs thereof to move along one of said guide tracks, said guide tracks being pivoted about verticallyaligned horizontal pivots and linked together such that they remain mutually parallel and spaced apart by a constant vertical distance as they pivot about their respective pivots.

In the escalator according to the invention, the steps are notionally free individually to assume a range of different orientations relative to the vertical. However, the orientation is controlled by the parallel guide tracks. Thus, as the tracks are pivoted, the actual distance apart of the tracks changes with their angle of pivoting but their spacing measured in a vertical direction remains constant. The only way in which the two wheels or rollers of a pair may continue to remain in engagement with the respective tracks, since the vertical spacing apart of the wheels or rollers is fixed is by the step mEsnbers maintaining their orientation with their upper surfaces level.

The step merrbers are preferably of at least substantially constant cross-section throughout their lengths and therefore they lend themselves to being produced by extrusion. Thus, for exarrple, each step aber may be an extruded length of aluminium.

Preferably the upper surface of each step member is generally flat. To enable the escalator to adopt either an upwardlyinclined or a downwardly-inclined operating orientation, the step eribers are preferably of symretrical cross section, preferably tapering sorrewhat from their upper surface downwards.

At at least one end of each step member are mounted the guide wheels or rollers. Preferably there is a pair of guide wheels or rollers at each end of each step member. For succinctness, they are referred to hereinafter simply as "wheels". The wheels of each pair at a given end are spaced apart by a predetermined vertical distance, which is a imn distance for all the pairs at the corresponding ends of the step members.

At one side of the escalator, that is at one end of the step zribers, and preferably at both said sides or ends, two mutually parallel guide tracks are located. The guide tracks are intended to receive the guide wheels and are therefore sized, shaped and spaced apart accordingly. Each guide track preferably takes the form of a channel defined by parallel edges or flanges, between which the corresponding guide wheels are constrained to move.

The vertical spacing apart of the two tracks at either or both sides of the escalator should be the sarge as the spacing apart of the two wheels of a pair, so that the individual step members adopt an orientation in which the upper surface is generally level.

Dverrent of the steps, that is operation of the escalator to convey people or goods up or down its slope, is effected by driving the guide wheels along the tracks. A particularly convenient way of driving these wheels is to provide a continuous chain or similar drive band which is engaged by or otherwise secured to a corresponding end of each step member. For example, axles carrying lower or upper guide wheels of each pair may engage such a continuous chain. Preferably there is such a drive means at each side of the escalator.

The two guide tracks at one or each side of the escalator are linked together so that they may together pivot about respective horizontal pivots. These pivots are aligned vertically and are conveniently spaced apart by the sarre distance as the distance apart of the guide wheels in each pair. As explained above, the guide tracks are in this way kept at a constant mutual vertical distance apart when their angular orientation with respect to the horizontal or vertical changes.

Preferably a platform affording access to the escalator is provided at one end, and preferably at both ends, of the escalator To assist such access, the step sibers preferably move along a generally horizontal linear path towards and away from the inclined length of the escalator within the region of the platform or platforms. This itovement is readily achieved in the escalator according to the present invention by providing horizontal sections of the guide tracks in this region. Transition of the guide wheels from the inclined to the horizontal sections of the guide tracks and vice versa may be assisted by the provision of one or more idler sprockets, around a part of the circumference of which the drive means, for example the continuous drive chain, may pass.

The escalator will normally be secured at one end and free at its other. For example, the escalator may be mounted at a quayside or jetty and extend to a ship's deck or, less preferably, be carried by the ship and extend to the shore. Preferably the escalator is designed to extend either upwardly or downwardly fran its fixed end as required, from which fixed end the drive means may conveniently operate. In one form of the escalator, the whole assembly is mounted upon a mobile carriage, which may be provided with road wheels to allow it to be moved around generally or may be arranged to run along fixed tracks, for example along a quayside. The escalator, especially in its mobile form, may also be used at an airport to provide access to and from aircraft of different heights above ground level.

The angle of operation of the escalator may initially be set by mechanical or manual methods operated from its fixed end. However, once the escalator is operating, with its "free" end now temporarily secured at, say, an access point to a ship, it is intended that the angle of operation will vary in response to the rising and falllng of the ship, both as a result of tide changes and also as loading or unloading of the ship progresses.

This varying of the angle of the escalator may be achieved mechanically or by the operation of, say, a lifting crane in response to instructions from electronic sensors. By virtue of the present invention, the escalator steps will remain level as the angle of the escalator varies.

The invention will now be further described with reference to the acccanpanying drawing, which illustrates, by way of example, the structure and operation of the driving end of one eml=odinnt of escalator according to the invention. The illustration shows the end of the escalator and associated platform, partly in vertical crossectional view.

The illustrated escalator carprises a nurrber of step members 1, each of which is formed from a length of extruded aluminium section, closed at its ends. Each step member 1 has a flat upper surface 2 and curves downwardly in section to a flat lower surface 3. For clarity, only seven of the step manbers are shown.

Each step member 1 has at each of its ends a pair of guide wheels 4, 5, mounted for rotation about axes parallel to the length of the step rrember. Guide wheels 4 engage in turn in guide tracks 6, 7 and 8 and guide wheels 3 engage in guide tracks 9, 10, 11, which are mounted parallel to the respective guide tracks 6, 7 and 8. Thus if, in the illustrated embDdim nt, the escalator is runing in a downward direction (clockwise overall as indicated by the arrows), then the wheels 4 traverse the track 6, enter successive linear, curved and linear sections of the track 7 and finally move upwardly along the track 8. Guide wheels 5 follow the tracks 9, 10 and 11 in a similar manner.In fact, the guide wheels 5 are mounted upon a continuous chain 12 which at its lower end is driven by a drive sprocket 13 and passes round an idler sprocket 14. Two idler sprockets corresponding to the sprockets 13 and 14 are also provided at the upper end of the escalator (not shown).

The vertical spacing between tracks 6 and 9, 7 and 10, and 8 and 11 respectively has a constant value, equal to the distance apart of the guide wheels 4 and 5 of each step member. Thus, when the drive sprocket 13 is rotated, the escalator functions in the manner of a conventional escalator, operating in a descending node as illustrated.

Guide track 6 is mounted for pivoting about a horizontal axis indicated by the numeral 15 and guide track 9 is similarly mounted for pivoting about an axis 16. The axes 15 and 16 are spaced apart by the sane amount as the distance between each pair of guide wheels 4 and 5. The tracks 6 and 9 are linked together so that when the angle of inclination to the horizontal of one of the tracks is changed by pivoting abut its axis, the angle of the other track changes by the sane amount. In the course of thds pivoting, the cFfiuGl shç,rtest dlst3rlce apart cf the tracks 6 and 9 changes.However, their distance apart in a vertical direction remains constant and thus the individual steps 1 are constrained by the guide wheels 4, 5 to remain level throughout pivoting of the guide tracks. Thus the angle of operation of the escalator can be adjusted to take account of the relative positions of the two locations to be linked by the escalator and the step niters 1 will remain level at all such angles.

The step members becarbe inverted in passing along the tracks 7, 10 and then follow an inverted return route up the guide tracks 8, 11 to the top of the escalator. The lower end of the escalator is enclosed within a box 17, the upper surface of which forms an access platform closely aligned with the surfaces 2 of step members 1 entering or leaving the box.

The illustrated escalator is designed to operate at any angle between an upwardly inclined angle of 40 degrees and a downwardly inclined angle of the sane amount. When the tracks 6, 9, 8 and 11 are pivoted to extend dovrnwards from the platform 17, then the guide chain 12 passes over an idler sprocket 18 (shown in broken line in the drawing), which then fur.ctions instead of idler sprocket 14.

Claims (12)

1. A variable-angle escalator which comprises a number of separate step mnbers each having an upper surface to support at least a part of the foot of a user of the escalator, a pair of guide wheels or rollers mounted upon at least one end of each step member, the wheels or rollers of each pair being spaced apart by a ccrnrron predetermined vertical distance, at least two parallel guide tracks, spaced apart vertically by said common distance, and drive means to cause a corresponding wheel or roller in each of said pairs to movie along one of said guide tracks, said guide tracks being pivoted about vertically-aligned horizontal pivots and linked together such that they remain mutually parallel and spaced apart by a constant vertical distance as they pivot about their respective pivots.

2. An escalator as claimed in claim 1, wherein each step member is of at least substantially constant crosssection throughout its length.

3. An escalator as claimed in claim 1 or 2, wherein each step member is of symnetrical cross-section.

4. An escalator as claimed in any of the preceding claims, having a said pair of guide wheels or rollers nounted upon each end of each step member.

5. An escalator as claimed in claim 4, having at least two said guide tracks located at each end of said step meCibers.

6. An escalator as claimed in any of the preceding claims, wherein the guide tracks are in the form of channels defined by parallel edges or flanges.

7. An escalator as claimed in any of the preceding claims, wherein said drive means comprises a continuous chain or similar drive band, which is engaged by or otherwise connected to a corresponding end of each step member.

8. An escalator as claimed in any of the preceding claims, having an access platform at one or both ends.

9. An escalator as claimed in claim 8, wherein the guide tracks have horizontal sections within the region of said platform or platforms.

10. An escalator as claimed in claim 9, having, within the region of said horizontal sections of the guide tracks, one or more idler sprockets, around a part of the circumference of which the drive means may pass.

11. An escalator as claimed in any of the preceding claims, mounted upon a mobile carriage.

12. A variable-angle escalator, substantially as hereinbefore described with reference to, and as illustrated in, the accowarlying drawing.