Misalignment monitoring in a people conveyor

Abstract

A people conveyor (1) comprises a truss (2) extending between two landing portions (20, 21); a band (12) of conveyance elements (13) forming a closed loop extending in a conveyance direction between the two landing portions (20, 21); a drive machine (25) configured for driving the band (12) of conveyance elements (13); and at least two magneto-inductive sensors (36a, 36b, 36c) mounted to the truss (2). The at least two magneto-inductive sensors (36a, 36b, 36c) are configured for providing sensor signals which allow determining the position and orientation of the drive machine (25) with respect to the truss (2).

Claims

1. People conveyor comprising: a truss extending between two landing portions; a band of conveyance elements forming a closed loop extending in a conveyance direction between the two landing portions; a drive machine configured for driving the band of conveyance elements; and at least two magneto-inductive sensors mounted to the truss and configured for detecting the position and/or the orientation of the drive machine with respect to the truss.

2. People conveyor according to claim 1 comprising at least two permanent-magnets, wherein each of the at least two permanent-magnets, is attached to the drive machine at a position opposite to one of the at least two magneto-inductive sensors, respectively.

3. People conveyor according to claim 1, wherein the at least two magneto-inductive sensors are spaced apart from each other in a horizontal direction and/or in a vertical direction.

4. People conveyor according to claim 1, wherein the at least two magneto-inductive sensors are arranged at the same height in a vertical direction.

5. People conveyor according to claim 1, wherein the drive machine comprises a drive member configured to be driven by the drive machine and in engagement with a transmission element.

6. People conveyor according to claim 5, wherein the drive member comprises a drive chain configured to drive the band of conveyance elements.

7. People conveyor according to claim 1, further comprising a controller configured for receiving sensor signals from the at least two magneto-inductive sensors and for determining the position and/or orientation of the drive machine from the received sensor signals.

8. People conveyor according to claim 7, wherein the controller is configured for determining a lateral position of the drive machine and/or an inclination of the drive machine with respect to a predefined orientation.

9. People conveyor according to claim 7, wherein the controller is configured for determining a deviation of the determined position/orientation of the drive machine from a predefined position/orientation of the drive machine, wherein the controller is further configured for issuing an alarm signal and/or for stopping the drive machine when the absolute value of said deviation exceeds a predetermined limit.

10. People conveyor according to claim 1, wherein the people conveyor comprises three magneto-inductive sensors attached to the truss and configured for detecting the position and orientation of the drive machine with respect to the truss.

11. People conveyor according to claim 10, wherein the three magneto-inductive sensors are arranged in a common virtual plane.

12. People conveyor according to claim 10, wherein the three magneto-inductive sensors are not arranged on a common straight line.

13. People conveyor according to claim 12, wherein the three magneto-inductive sensors are arranged on the corners of a virtual rectangular triangle.

14. People conveyor according to claim 1, wherein the people conveyor is an escalator (1a) and the conveyance elements are steps, or wherein the people conveyor is a moving walkway (1b) and the conveyance elements are pallets.

15. Method of operating a people conveyor according to claim 1, wherein the method includes determining the position and/or the orientation of the drive machine with respect to the truss based on sensor signals provided by the at least two magneto-inductive sensors.

16. Method of claim 15, wherein the method includes determining a difference between the determined position of the drive machine and a predefined position of the drive machine, wherein the method further includes issuing an alarm signal when the absolute value of said difference exceeds a predetermined alarm limit and/or stopping the drive machine when the absolute value of said difference exceeds a predetermined stop limit.

17. Method of initializing a people conveyor according to claim 1, wherein the method includes determining the distances (.sub.A, .sub.B) of the drive machine with respect to the truss based on sensor signals provided by the at least two magneto-inductive sensors while the drive machine is properly aligned, and storing said distances (.sub.A, .sub.B) as reference distances (.sub.A0, .sub.B0).

Description

DRAWING DESCRIPTION

(1) In the following, exemplary embodiments of the invention are described with reference to the enclosed figures.

(2) FIG. 1 depicts a schematic side view of an escalator;

(3) FIG. 2 depicts a schematic side view of a moving walkway;

(4) FIG. 3 depicts a perspective view of the drive machine; and

(5) FIG. 4 depicts a top view of the drive machine.

DETAILED DESCRIPTION

(6) FIG. 1 depicts a schematic side view of a people conveyor 1, in particular of an escalator 1a, comprising a truss 2 and a band 12 of conveyance elements 13 (steps 13a) extending in a longitudinal conveyance direction between two landing portions 20, 21. The conveyance elements 13 comprise rollers 23 guided and supported by guide rails (not shown). For clarity, only some of the conveyance elements 13 are depicted in FIG. 1, and not all conveyance elements 13/rollers 23 are provided with reference signs.

(7) In turnaround portions 17 next to the landing portions 20, 21, the band 12 of conveyance elements 13 passes from an upper conveyance portion 16 into a lower return portion 18, and vice versa. A conveyance chain 15 extending along a closed loop is connected to the band 12 of conveyance elements 13.

(8) The conveyance chain 15 is configured for driving the band 12 of conveyance elements 13. The conveyance chain 15 is driven by a conveyance sprocket or sheave 32 mounted to a rotating shaft 30. A drive machine 25 comprising a motor 29 is configured for driving the rotating shaft 30 and in consequence the conveyance sprocket or sheave 32 and the conveyance chain 15 via a transmission element 27.

(9) The transmission element 27 may be a drive chain or drive belt engaging with a drive member (drive sprocket or sheave) 26 of the drive machine 25 and the conveyance sprocket or sheave 32 mounted to a rotating shaft 30. In such a configuration, the conveyance sprocket or sheave 32 may comprise two gear rims (not shown), a first gear rim engaging with the conveyance chain 15, and a second gear rim engaging with the transmission element 27. The first and second gear rims may have the same diameter/number of teeth, or the diameters/numbers of teeth of the two gear rims may be different.

(10) Balustrades 4 supporting moving handrails 6 extend parallel to the conveyance portion 16.

(11) FIG. 2 depicts a schematic side view of a people conveyor 1, which is provided as a moving walkway 1b.

(12) The moving walkway 1b comprises a supporting truss (not shown in FIG. 2), and an endless band 12 of conveyance elements 13 (pallets 13b) moving in a longitudinal conveyance direction in an upper conveyance portion 16 and opposite to the conveyance direction in a lower return portion 18. Landing portions 20, 21 are provided at both ends of the moving walkway 1b. In turnaround portions 17 next to the landing portions 20, 21 the band 12 of conveyance elements 13 passes from the conveyance portion 16 into the return portion 18, and vice versa. Balustrades 4 supporting moving handrails 6 extend parallel to the conveyance portion 16.

(13) Similar to the embodiment shown in FIG. 1, the band 12 of conveyance elements 13 is connected with an endless conveyance chain 15. In at least one of the turnaround portions 17, the endless conveyance chain 15 is in engagement with a conveyance sprocket or sheave 32. When the moving walkway 1b is operated, the conveyance sprocket or sheave 32 is driven by a motor 29 of a drive machine 25 via a transmission element 27 for driving the band 12 of conveyance elements 13.

(14) The transmission element 27 may be a drive chain or drive belt engaging with a drive member (drive sprocket or sheave) 26 of the drive machine 25 and the conveyance sprocket or sheave 32 mounted to a rotating shaft 30. In such a configuration, the conveyance sprocket or sheave 32 may comprise two gear rims (not shown), a first gear rim engaging with the conveyance chain 15 and a second gear rim engaging with the transmission element 27. The first and second gear rims may have the same diameter/number of teeth, or the diameters/numbers of teeth of the two gear rims may be different.

(15) FIG. 3 shows a perspective view of the drive machine 25, and FIG. 4 shows a top view thereof. The drive machine 25 may be a drive machine 25 of an escalator 1a as depicted in FIG. 1, or of a moving walkway 1b as depicted in FIG. 2.

(16) The drive machine 25 is mounted to and supported by two bars 3a, 3b of the truss 2. The two bars 3a, 3b are the only components of the truss 2 shown in FIG. 3. No parts of the truss 2 are depicted in FIG. 4.

(17) In the embodiment depicted in FIGS. 3 and 4, the transmission element 27 is a double drive chain engaging with a double drive member 26. The double drive chain is depicted only in FIG. 3, but not in FIG. 4. The skilled person understand that employing a double drive chain is only an example and that alternative transmission elements 27, e.g. a single chain or a toothed belt (not shown), may be used instead.

(18) A plurality of mechanical adjustment mechanisms 34 are mounted to the bars 3a, 3b of the truss 2. The mechanical adjustment mechanisms 34 allow adjusting the position of the drive machine 25 with respect to the bars 3a, 3b in order to align the drive member 26 at the desired position and with the proper orientation allowing a smooth engagement of the transmission element 27 with the drive member 26.

(19) When the drive machine 25 is arranged and oriented properly, a rotation axis R of the drive member 26 extends orthogonally to a plane P in which the transmission element 27 is configured to extend.

(20) Two magneto-inductive sensors 36a, 36b facing a side surface 24 (see FIG. 3) of the drive machine 25 are mounted to the bars 3a, 3b. The magneto-inductive sensors 36a, 36b are configured for detecting the distances .sub.A, .sub.B between the respective magneto-inductive sensor 36a, 36b and the opposing side surface 24 of the drive machine 25, respectively.

(21) The magneto-inductive sensors 36a, 36b in particular are configured for detecting their respective distances .sub.A, .sub.B from corresponding permanent-magnets 38a, 38b attached to the side surface 24 of the drive machine 25 facing the magneto-inductive sensors 36a, 36b.

(22) The magneto-inductive sensors 36a, 36b and the corresponding permanent-magnets 38a, 38b are arranged at the same height in a vertical direction, and they are spaced apart from each other in a distance L.sub.1 in a horizontal direction.

(23) The first magneto-inductive sensor 36a and the corresponding permanent-magnet 38a are arranged in a distance L.sub.2 from the rotation axis R of the drive member 26 in the horizontal direction.

(24) The people conveyor 1 further comprises a controller 40 (see FIG. 4). The controller 40 is electrically connected with the magneto-inductive sensors 36a, 36b by signal lines 39a, 39b for receiving sensor signals from the magneto-inductive sensors 36a, 36b. The controller 40 is configured for determining the position and/or the orientation of the drive machine 25 and/or of the drive member 26 with respect to the truss 2 by analyzing the sensor signals received from the magneto-inductive sensors 36a, 36b.

(25) After the drive machine 25 has been properly aligned, e.g. after installation and/or maintenance of the people conveyor 1, the controller 40 may be initialized by detecting the distances .sub.A, .sub.B between the magneto-inductive sensors 36a, 36b and the corresponding permanent-magnets 38a, 38b in said properly aligned configuration, and by storing said distances .sub.A, .sub.B as reference distances .sub.A0, .sub.B in a memory 42 of the controller 40.

(26) During the following operation of the people conveyor 1, the controller 40 continuously or periodically determines the current actual distances .sub.A, .sub.B between the magneto-inductive sensors 36a, 36b and the corresponding permanent-magnets 38a, 38b from the received sensor signals. Based on this information, the controller 40 determines the current position and orientation of the drive machine 25 and/or of the drive member 26 with respect to the truss 2.

(27) The controller 40 in particular may be configured for calculating deviations (differences) A, B of the actual distances .sub.A, .sub.B from the reference distances .sub.A0, .sub.B0:
A=.sub.A.sub.A0
B=.sub.B.sub.B0

(28) From these deviations A, B, the controller 40 may further determine the angular misalignment of the drive machine from the predefined orientation:

(29) $={\tan }^{-1}\left(\frac{B-A}{L_1}\right)$ and the lateral offset .sub.offset of the drive member 26 along its rotation axis R from the predefined position.
.sub.offset=L.sub.2tan .

(30) The deviations A, B, the misalignment and/or the lateral offset .sub.offset may be compared to corresponding predefined limits stored within the memory 42 of the controller 40. The controller 40 in particular may be configured for issuing an alarm signal in case at least one of the predefined limits is exceeded by the absolute value of at least one of the deviations A, B, the misalignment and the lateral offset .sub.offset, respectively.

(31) For example, issuing a first alarm signal (maintenance signal) may cause a mechanic to visit the people conveyor 1 in order to realign the drive machine 25. Alternatively or additionally, a second alarm signal (stop signal) may stop operating the drive machine 25.

(32) At least two limits may be assigned to at least one of the deviations A, B, the misalignment and/or the lateral offset .sub.offset, respectively. The at least two limits may include a lower limit and an upper limit, which is larger than the lower limit.

(33) A mechanic may be ordered to visit the people conveyor 1 for realigning the drive machine 25 in case at least one of the lower limits (maintenance limits) is exceeded by the absolute value of at least one of the deviations A, B, the misalignment and/or the lateral offset .sub.offset, respectively. Any further operation of the people conveyor 1 may be stopped in order to avoid (further) damage of the people conveyor 1, in particular of the transmission element 27 and/or the drive member 26, in case at least one of the upper limits (stop limits) is exceeded by the absolute value of at least one of the deviations A, B, the misalignment and/or the lateral offset .sub.offset, respectively.

(34) In a further (optional) configuration, the people conveyor 1 comprises at least one additional (third) magneto-inductive sensor 36c and at least one corresponding additional (third) permanent-magnet 38c attached to the side surface 24 of the drive machine 25 facing the additional magneto-inductive sensor 36c (See FIG. 3).

(35) Three magneto-inductive sensors 36a, 36b 36c may be arranged in a common virtual plane extending parallel to a side surface 24 of the drive machine 25.

(36) The three magneto-inductive sensors 36a, 36b 36c may be arranged in a configuration in which they are not arranged on a common straight line, the three magneto-inductive sensors 36a, 36b 36c in particular may be arranged on the corners of a virtual rectangular triangle.

(37) Such a configuration comprising at least three magneto-inductive sensors 36a, 36b 36c allows determining the inclination (angular misalignment) of the drive machine 25 not only in one dimension, in particular in the horizontal dimension, as described before, but also in a second dimension. It in particular allows determining deviation from a vertical plane, which is oriented orthogonally with respect to the first dimensions.

(38) While the invention has been described with reference to exemplary embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adopt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention is not limited to the particular embodiments disclosed, but that the invention includes all embodiments falling within the scope of the claims.

REFERENCES

(39) 1 people conveyor 1a escalator 1b moving walkway 2 truss 3a, 3b bars of the truss 4 balustrade 6 moving handrail 12 band of conveyance elements 13 conveyance elements 13a steps 13b pallets 15 conveyance chain 16 conveyance portion 17 turnaround portion 18 return portion 20, 21 landing portions 23 rollers 24 side surface of the drive machine 25 drive machine 26 drive member 27 transmission element 29 motor 30 rotating shaft 32 conveyance sprocket or sheave 34 mechanical adjustment mechanism 36a, 36b, 36c magneto-inductive sensors 38a, 38b, 38c permanent-magnets 39a, 39b signal lines 40 controller 42 memory L1 distance between magneto-inductive sensors in the horizontal direction L2 distance between the first magneto-inductive sensor and center of the drive sprocket R rotation axis .sub.A, .sub.B distances between the magneto-inductive sensors and the corresponding permanent-magnets .sub.A0, .sub.B0 reference distances .sub.offset lateral offset of the drive machine angular misalignment of the drive machine