GB2205803A

GB2205803A - Passenger conveyor system

Info

Publication number: GB2205803A
Application number: GB08812536A
Authority: GB
Inventors: Alan Randle; Malcolm Gregory Hewitt
Original assignee: Dunlop Ltd
Current assignee: Dunlop Ltd
Priority date: 1987-06-19
Filing date: 1988-05-26
Publication date: 1988-12-21
Anticipated expiration: 2008-05-26
Also published as: KR890000337A; GB2205803B; JPS6417792A; GB8714457D0; GB8812536D0

Abstract

A pasenger conveyor system (10) of the kind incorporating an endless belt (15) in which the drive mechanism for the belt is reduced in size by the use of terminal drums (16, 17) having diameters of less than 350 millimetres, enabling the system to be surface-mounted on an existing floor, eliminating the need for excavation. Alternatively, a shallow excavation may be employed so that the conveyor height is at or near to normal floor level. <IMAGE>

Description

PASSENGER CONVEYOR SYSTEM This invention relates to passenger conveyor systems of the kind in which a moving belt is provided, passengers stepping on to one end of an upper run of the belt and being transported thereby to the other end.

Systems of this kind, which are commonly installed in airports and similar locations, normally require substantial excavation to accommodate the necessary machinery below floor level : this tends to restrict the installation of such systems to new buildings, and even when the necessary accommodation can be provided in the building design there is inevitably a substantial cost incurred in providing the necessary underfloor installation. Further, maintenance of the belt and its associated drive mechanism is difficult to arrange when the machinery is below floor level and access is, as a result, difficult.

One object of the present invention is to provide a passenger conveyor system in which the problems discussed above are reduced or eliminated.

According to the invention, a passenger conveyor system comprises an endless belt having an upper belt run supported for longitudinal movement of the belt by support rollers carried on a support structure, the belt passing around a pair of terminal drums, one of the terminal drums being drivable to move the belt so as to convey passengers on the upper belt run, wherein the terminal drums are each less than 350 millimetres in diameter.

Hitherto, passenger conveyor systems of the kind described above have always employed terminal drums having a diameter of the order of 600 millimetres. By drastically reducing the drum diameter it has now been found that the possibility is opened up of reducing the vertical dimensions of the drive mechanisms and belt supporting structure, to such an extent that the entire system can be mounted above a floor with no part having to be recessed into the floor. Alternatively, the system could, in a compromise situation, be accommodated with relatively smaller recessed portions in situations where this may be advantageous.

Passenger conveyor systems must normally make provision for a moving handrail on each side, and in the system in accordance with the invention this may conveniently be achieved by coupling the handrail drive for the terminal drum to a pair of sFrcdets carried on the drum drive shaft.

One embodiment of the invention will now be described, by way of example, with reference to the accompanying drawings, in which Figure 1 is a diagrammatic side elevation showing one end portion of a passenger conveyor system in accordance with the invention; Figure 2 is a similar view to Figure 1 showing the other end portion; Figure 3 is a cross-sectional elevation on the line III-III of Figure 2; Figure 4 is a cross-sectional elevation on the line IV-IV of Figure 2; Figure 5 is a similar view to Figure 1 showing more detail of the conveyor belt tensioning arrangement, and Figure 6 is a vertical section on the line VI-VI of Figure 5.

The passenger conveyor system 10 illustrated in the drawings is intended to be mounted with its lower surface 12 supported on a suitable floor, the whole system thus standing above floor level. The passengers are conveyed on the upper run 14 of an endless belt 15 which passes around a driven drum 16 at one end of the conveyor and a freely rotatable drum 17 at the other end, the drum 17 being adjustable in position as indicated by dotted lines in Figure 1 to hold the belt at a desired longitudinal tension.The belt 15 is a flexible reinforced rubber belt of the transversely rigid type, comprising a reinforcement having transversely extending steel cords in vertically separated layers which provide sufficient beam stiffness to enable the belt to be supported on edge support rollers 20, whilst retaining sufficient flexibility in the longitudinal direction to enable the belt to bend around the drums at the ends of the conveyor. The longitudinal reinforcement of the belt may be provided by a layer of longitudinally-extending steel cords. Access to the conveyor is provided by a ramp 22 at one end and passengers leave the conveyor by a ramp 24 at the other end, an entrance platform 25 and an exit platform 26 being provided.

The belt 15 is longitudinally grooved, and comb assemblies 27 and 28 are provided.

The platforms 25 and 26 are constructed integrally with a longitudinally extending support structure 30 comprising side supports 32, 34 which extend for the whole length of the conveyor between the platforms. Cross members 36 hold the side supports at fixed spacing from one another, and suitably braced side frames 40, 41 support inner and outer panels 44, 45; 46, 47 respectively, fixed balustrades 50, 51 providing support for moving handrails 52, 54 of conventional type.

The lower run 60 of the belt 15 is supported along its length by rollers 61, with larger rollers 63, 64 adjacent the terminal drums 16 and 17.

Drive for the drum 16 is provided by an electric motor 70 coupled to the drum 16 by sprockets 72, 73, 74 and 75, and associated chains 76 and 77. Drive for the handrail 54 is transmitted via sprockets 80 carried one at each end of the shaft supporting the drum 16, chains 81, and sprockets 82 secured to drive wheels 83, the chains 81 also passing around freely rotatable sprockets 85, 86. The other ends of the handrail runs are supported on similar non-driven wheels 84.

Handrail guide rollers 87, 88, 89, 90 are provided at opposite ends of the conveyor respectively, and a series of tensioning rollers 92 - 96 is provided adjacent the non-driven handrail support wheel 84 and mounted on a suitable mechanism to enable the rollers 92 - 96 to be moved e.g. as shown in dotted lines to tension the handrail.

In order to provide means for tensioning the conveyor belt 15, the bearings for the drum 17 are mounted so as to be slidable in a substantially horizontal direction to move the drum 17 as indicated in dotted lines in Figure 1.

This arrangement creates a potential difficulty in accommodating the comb 27 which has been overcome as illustrated in Figures 5 and 6.

The comb assembly 27 comprises a comb plate 101 pivotted about a horizontal axis on pivot bearings 103, 104. secured to the respective side supports and mounted above the level of the conveyor belt within spaces enclosed by the side panels 106, 107 of the support structure (known as 'kick strips'). The plate 101 is also guided for horizontal movement transversely with respect to the belt surface by bearings 109, 110 which are also mounted above the level of the conveyor belt.

Thus the comb plate 101 may be deflected upwardly if any object is trapped between its teeth 112 and the belt 15, operating a limit switch (not shown) which stops the conveyor.

By allowing horizontal transverse movement of the comb its teeth are enabled to track the belt grooves and maintain their engagement in the grooves when any sideways belt movement occurs.

The tensioning means for the belt comprises a pair of draw bars (not shown) adjustably mounted by screwed connections at their rear ends in the support structure and secured at their other ends to journals (not shown) for the drum 17 which are slidable along rails (not shown) to move the drum 17 in a substantially horizontal direction.

The comb plate segment incorporating the teeth 112 is designed to taper longitudinally as shown in Figure 5 in order to reduce, so far as possible, the extent to which the upper surface of the comb plate is elevated above the belt surface.

It will be noted that even when the drum 17 is in its furthest forward position (for minimum tension), the teeth of the comb need to extend for some distance over the upper belt surface in order to meet the upper belt surface at the line where it starts to descend around the final support roller 120. This places a considerable constraint on the design of the comb teeth, which are therefore provided with a long tapering profile as shown in Figure 5, and the need to provide for longitudinal movement of the drum 17 also involves the need for the whole of the comb plate 101 to be of shallow depth in order to clear the belt upper surface in all positions of the drum 17. The positioning of the pivot bearings 103, 104 and bearings 109, 110 above the belt surface is an important factor in enabling the comb plate structure to be positioned near to the belt surface.

It will be noted that the whole of the drive mechanism is contained within a vertical space bounded by the platform 26 and the lower surface 12 of the conveyor system : in a practical example employing a drum diameter of 300 millimetres this enables a platform height of 400 millimetres to be achieved and with a drum diameter of 250 millimetres the platform height may be further reduced to 335 millimetres. These heights are sufficiently low to permit the installation of the system on the surface of an existing floor in most locations, avoiding the necessity for excavation. Alternatively, a shallow excavation may be employed so that the conveyor height is at or near to normal floor level.

Where full advantage is taken of the avoidance of the need to recess the drive mechanism below floor level, the drive mechanism is freely accessible for maintenance purposes by the simple removal of a side panel.

In an alternative handrail drive arrangement, the motor may be arranged to drive a layshaft immediately below the handrail drive wheels 83 to provide a more direct drive through short vertically-aligned chains. Conveniently, the motor may then be positioned between the handwheel drive layshaft and the drum 16.

Claims

CLAIMS:

1. A passenger conveyor system comprising an endless belt having an upper belt run supported for longitudinal movement of the belt by support rollers carried on a support structure, the belt passing around a pair of terminal drums, one of the terminal drums being drivable to move the belt so as to convey passengers on the upper belt run, wherein the terminal drums are each less than 350 millimetres in diameter.

2. A passenger conveyor system according to Claim 1 mounted above a floor.

3. A passenger conveyor system according to Claim 1 having a portion thereof recessed into a floor.

4. A passenger conveyor system according to any of the preceding claims wherein the belt is of the transversely rigid type, supported by edge support rollers.

5. A passenger conveyor system according to any of the preceding claims wherein the system is mounted above a floor having ramps to provide access to the conveyor.

6. A passenger conveyor system according to Claim 5 wherein entrance and exit platforms are provided.

7. A passenger conveyor system according to any of the preceding claims comprising a pair of moving handrails and wherein a drive for the terminal drum from an electric motor is transmitted by a series of sprockets and chains, the terminal drum being supported on a shaft carrying handrail drive sprockets and handrail drive chains being provided to transmit the drive from the handrail drive sprockets to handrail drive wheels.

8. A passenger conveyor system according to Claim 7 wherein a series of movable tensioning rollers is provided for each handrail.

9. A passenger conveyor system according to any of the preceding claims wherein the terminal drums each haye a diameter of about 300 millimetres.

10. A passenger conveyor system according to any of the preceding claims wherein the terminal drums each have a diameter of about 250 millimetres.

11. A passenger conveyor system according to any of the preceding claims wherein tensioning means is provided, one of the terminal drums being movable in a substantially horizontal direction, and means being provided for moving the said terminal drum.

12. A passenger conveyor system according to Claim 11 wherein the belt passes over a final support roller before passing around the movable terminal drum and wherein a comb assembly having teeth engaging longitudinal grooves in the belt is positioned over the final support roller and extends over the terminal portion of the belt, the comb assembly having a shallow tapering profile to permit horizontal movement of the drum.

13. A passenger conveyor system according to Claim 12 wherein the comb assembly comprises a plate supported so as to pivot about a horizontal axis in bearings secured to the support structure above the belt.

14. A passenger conveyor system according to Claim 13 wherein the bearings for the comb assembly are mounted within spaces enclosed by side panels of the support structure.

15. A passenger conveyor system according to Claim 13 or Claim 14 wherein a limit switch is positioned so as to be actuated by upward deflection of the comb assembly to stop the conveyor.

16. A passenger conveyor system constructed and arranged substantially as described in the Description and illustrated in the Drawings.