Belt-driven escalator

Abstract

A belt-driven escalator 2 is provided that includes a plurality of escalator steps 4 arranged to travel along an inclined conveyance path 101; a drive belt 10, 1010 connected to the plurality of escalator steps 4; a drive system 24 arranged to drive the drive belt 10, 1010 so as to propel the plurality of escalator steps 4 along the inclined conveyance path 101; and a belt support structure 22, 1022 including at least one belt wheel 206, 1206 arranged to support the drive belt 10, 1010 so as to support the plurality of escalator steps 4.

Claims

1. A belt-driven escalator (2) comprising: a plurality of escalator steps (4) arranged to travel along an inclined conveyance path (101); a drive belt (10, 1010) directly and rotatably connected to the plurality of escalator steps (4); a drive system (24) arranged to drive the drive belt (10, 1010) so as to propel the plurality of escalator steps (4) along the inclined conveyance path (101); a belt support structure (22, 1022) comprising at least one belt wheel (206, 1206) arranged to support the drive belt (10, 1010) so as to support the plurality of escalator steps (4); a step track (18) along which the steps (4) are arranged to travel during passenger conveyance; wherein the belt support structure (22, 1022) is arranged to unload the step (4) and/or a support track (20) at at least one point on the conveyance path (101); wherein the belt support structure (22, 1022) is arranged to lift the steps (4) entirely away from the step track (18) and/or the support track (20) at at least one point on the conveyance path (101).

2. The belt-driven escalator (2) as claimed in claim 1, wherein the conveyance path (101) comprises an upper transition region (110) between an inclined region (106) and a non-inclined landing region (104), and the belt support structure (22, 1022) is arranged to provide support to the steps (4) in the upper transition region (110).

3. The belt-driven escalator (2) as claimed in claim 2, wherein the belt support structure (22, 1022) is arranged to provide curved support to the drive belt (10, 1010) in the upper transition region (110).

4. The belt-driven escalator (2) as claimed in claim 3, wherein the belt support structure (22, 1022) is arranged to provide curved support to the drive belt (10, 1010) with a curve that matches a curve of the upper transition region (110).

5. The belt-driven escalator (2) as claimed in claim 4, wherein the curve of the upper transition region (110) comprises a radius of curvature of at least 0.5 m.

6. The belt-driven escalator (2) as claimed in claim 1, wherein the belt support structure (22, 1022) comprises a single belt wheel (206, 1206).

7. The belt-driven escalator (2) as claimed in claim 1, wherein the belt support structure (22, 1022) comprises a plurality of coplanar belt wheels (206, 1206).

8. The belt-driven escalator (2) as claimed in claim 1, wherein the at least one belt wheel (206, 1206) is mounted via a ball bearing.

9. The belt-driven escalator (2) as claimed in claim 1, wherein the drive belt (10, 1010) is toothed and the at least one belt wheel (206, 1206) comprises a sprocket arranged to engage with the toothed drive belt (10, 1010).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Certain examples of the present disclosure will now be described with reference to the accompanying drawings in which:

(2) FIG. 1 shows an escalator according to an example of the present disclosure;

(3) FIG. 2 shows a cross-section view of an upper part of the escalator;

(4) FIG. 3 shows a partial cutaway view of the escalator;

(5) FIGS. 4 to 7 show further partial cutaway views of the escalator;

(6) FIG. 8 shows a belt support structure according to an example of the present disclosure;

(7) FIG. 9 shows a partial view of the belt support structure;

(8) FIG. 10 shows a side view of the belt support structure;

(9) FIG. 11 shows a belt support structure according to another example of the present disclosure; and

(10) FIG. 12 shows a partial view of the belt support structure of FIG. 11.

DETAILED DESCRIPTION

(11) FIG. 1 shows a belt driven escalator 2 comprising a plurality of escalator steps 4 arranged to travel along an escalator conveyance path 101 to convey passengers. The conveyance path 101 comprises a lower landing region 102, an upper landing region 104 and an inclined region 106 located between the landing regions 102, 104. The conveyance path 101 comprises a lower transition region 108 between the inclined region 106 and the lower landing region 102 and an upper transition region 110 between the inclined region 106 and the upper landing region 104. In the upper transition region 110, the steps 4 transition from travelling at an incline in the inclined region 106 to travelling parallel to the ground in the non-inclined upper landing region 104.

(12) FIGS. 2-7 show various partial cutaway views of the escalator 2 in the upper transition region 110. Each step 4 comprises a tread surface 6 and a front surface 8. Each step 4 is rotatably connected to two parallel drive belts 10, although only one (e.g. centrally located) belt may be used in other examples. The belts 10 are driven by a drive system 24 to propel the plurality of escalator steps 4 along the conveyance path 101.

(13) Each escalator step 4 comprises a pair of step rollers 12 and a pair of support rollers 14. The tread surface 6 extends from the front surface 8 to a rear edge 16. The step rollers 12 are connected to the step 4 near the rear edge 16, with one step roller 12 at each side of the rear edge 16 (not all step rollers are shown in FIGS. 2-7). The support rollers 14 are connected to the step 4 near the bottom of the front surface 8, with one support roller 14 on each side of each step 4. The drive belts 10 are connected to each step 4 such that the axes of rotation of the support rollers 14 pass through the drive belts 10 when they are connected, to reduce the application of off-axis forces (i.e. a moment) to the support rollers 14.

(14) As the steps are propelled along the conveyance path 101, the step rollers 12 travel along two parallel step tracks 18 and two parallel support tracks 20. The step tracks 18 and support tracks 20 are arranged such that the tread surface 6 of each step 4 remains horizontal (i.e. parallel to the ground) throughout passenger conveyance. For example, in the curved upper and lower transition regions 108, 110 the step tracks 18 and support tracks 20 diverge from one another and are similarly curved to keep the steps 4 level.

(15) As mentioned above, in the upper transition region 110 the steps 4 transition from travelling at an incline to travelling parallel to the ground (when the escalator 2 is operated in an upwards direction; an opposite transition occurs when the escalator 2 is driven in a downwards direction). The tension force in the drive belts 10 in the upper transition region 110 thus has a component which urges the steps 4 (via the support rollers 14) into the support tracks 20. It will be appreciated that in other examples in which the belt is connected to a different location on the step, the tension forces may be applied through the step rollers 12 against the step tracks 18 or indeed through both the step rollers 12 and the support rollers 14 against both the step tracks 18 and support tracks 20.

(16) The step tracks 18 and support tracks 20 (and the step rollers 12 and support rollers 14) could simply be engineered to be strong enough to withstand this additional force in the upper transition region 110. However, this would either cause them to be unnecessarily strong in other regions, or require them to have a complex structure with different levels of strength in different regions. Instead, in this example the escalator 2 comprises a belt support structure 22 in the upper transition region 110 that is arranged to support the escalator steps 4 via the drive belts 10. The belt support structure 22 is arranged to at least partially unload the support tracks 20 (and consequently the support rollers 14) in the upper transition region 110, and may even be arranged to fully unload, i.e. entirely lift the support rollers 14 away from the support tracks 20 in the transition region. The support rollers 14 and support tracks 20 may thus be designed to provide only the support required in other regions of the conveyance path 101, with the belt support structure 22 providing additional support in the upper transition region 110. As discussed above, sections of the support tracks 20 may be omitted in the region where full support is provided by the belt support structure 22. Again, it will be appreciated that in other examples where the belt connection is made to a different part of the step 4, the support provided by the belt support structure 22 may instead partially or fully lift the step rollers 12 from the step tracks 18 or may partially or fully lift both sets of rollers 12, 14 from both tracks 18, 20.

(17) The belt support structure 22, which is shown in more detail in FIGS. 8, 9 and 10, comprises a frame 204 on which six belt wheels 206 are mounted. The belt wheels 206 of the belt support structure 22 are arranged in two parallel groups of three belt wheels 206 for supporting the two drive belts 10 of the escalator 2 (i.e. one group of three belt wheels 206 for each belt 10). However, other configurations are possible, e.g., comprising a single belt wheel 206 or group of belt wheels 206 for supporting a single drive belt 10. As shown in FIGS. 8, 9 and 10, the belt wheels 206 are all the same size (i.e. the same radius), and are mounted to the frame 204 which is curved so as to match the curve of the transition region 110. Therefore the envelope of the belt wheels 206 also matches the curve of the transition region 110 and therefore provides the appropriate support shape for the drive belt 10 in the transition region 110 even though the support rollers 14 are not in contact with the support tracks 20 in this region. Accordingly the steps 4 are maintained in their appropriate horizontal orientation as required.

(18) The belt wheels 206 are toothed (i.e. they comprise sprockets) to engage with and provide even support to the toothed drive belts 10. In each group of three belt wheels 206, the belt wheels 206 are coplanar (i.e. they are aligned in a common plane perpendicular to their axes of rotation), to provide support over a greater length of the drive belt 10 than could be provided by a single belt wheel 206 of the same radius. However, in some examples a single belt wheel 206 may be used (e.g. with the same and/or a larger radius).

(19) The belt wheels 206 in each group are arranged to provided curved support to a drive belt 10, i.e. the points at which the drive belt 10 contacts the belt wheels 206 when being supported thereby defines a curve. The curve of the belt wheels 206 matches the curve of the transition region 110 of the conveyance path 101 to ensure even support of the belts 10 as the steps 4 travel through the transition region 110 and thus provide a smooth ride for passengers of the escalator 2. For example, the transition region 110 and the curve of the belt wheels 206 may both comprise an arc 208 of a circle with radius R (shown in FIG. 10).

(20) As shown in FIG. 9, each belt wheel 206 is rotatably mounted to the frame 204 by a pair of bearings 208.

(21) In this example, all of the belt wheels 206 have the same width (in a direction parallel to their axes of rotation) and the same radius. Because the belt wheels 206 in this example have the same radius, their axes of rotation also define a curve matching arc 208.

(22) FIGS. 2-7 show various partial cutaway views of the belt driven escalator 2, in which many of the components of the escalator 2 (e.g. including the steps 4 and the drive belts 10 in FIGS. 6 and 7) have been omitted to allow the depiction of other components. The escalator 2 further comprises a truss 28 that provides the overall structure of the escalator 2. The step tracks 18 and support tracks 20, and the belt support structure 22 are rigidly attached to the truss 28. The escalator 2 also comprises a drive system 24. The drive system 24 comprises a motor 26 that is coupled to two drive sprockets 30. The drive sprockets 30 are configured to engage the drive belts 10. The motor 26 drives the drive sprockets 30 to rotate, thus driving the drive belts 10 to propel the steps 4 along the conveyance path 101. The drive system 24 is a direct drive system, compact enough to be located underneath the upper landing region 104 of the conveyance path 101. This reduces the footprint of the escalator 2.

(23) FIGS. 11 and 12 show an alternative belt support structure 1022. The belt support structure 1022 comprises a frame 1204 on which six belt wheels 1206 are mounted. The belt wheels 1206 of the belt support structure 1022 are arranged in two parallel groups of three belt wheels 1206 for supporting two drive belts 1010 (only one belt 1010 is shown in FIG. 11) of an escalator (i.e. one group of three belt wheels 1206 for each belt 1010). Each drive belt 1010 comprises two parallel sub-belts 1011, separated by and joined together via a series of belt rollers 1013. Each belt wheel 1206 comprises a central groove 1250 to accommodate the belt rollers 1013 as the belt 1010 passes over the belt wheels 1206.

(24) As shown in FIG. 12, each belt wheel 1206 is rotatably mounted to the frame 1204 by a pair of bearings 1208.

(25) While the disclosure has been described in detail in connection with only a limited number of examples, it should be readily understood that the disclosure is not limited to such disclosed examples. Rather, the disclosure can be modified to incorporate any number of variations, alterations, substitutions or equivalent arrangements not heretofore described, but which are commensurate with the scope of the disclosure. Additionally, while various examples of the disclosure have been described, it is to be understood that aspects of the disclosure may include only some of the described examples. Accordingly, the disclosure is not to be seen as limited by the foregoing description, but is only limited by the scope of the appended claims.