Escalator and method for detecting excessive tension at handrail
By installing temperature sensors and reference sensors on the escalator handrails, the temperature changes of the handrails can be monitored in real time, solving the problem of detecting excessive handrail tension and extending the service life of the handrails.
Patent Information
- Application Number
- CN202480044983.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2023-09-13
- Filing Date
- 2024-07-01
- Publication Date
- 2026-01-30
AI Technical Summary
In existing escalators, it is difficult to effectively detect excessive handrail tension, which leads to a shortened lifespan of the handrails.
By installing temperature sensors and reference temperature sensors on the handrails, excessive tension can be detected by utilizing temperature changes. This information is then compared with the data from the processing unit to achieve real-time monitoring and adjustment of the handrail tension.
It effectively detects and prevents wear and aging of handrails caused by excessive tension, thus extending the service life of the handrails.
Smart Images
Figure CN121443546A_ABST
Abstract
Description
Technical Field
[0001] This disclosure generally relates to escalators, including moving walkways. In particular, this disclosure relates to an escalator comprising: a support structure; a plurality of steps or treads or moving belts guided in a circular manner within the support structure and forming a path; at least one first handrail guided in a circular manner and directional about a first upper turning column and a first lower turning column, respectively; and at least one first tensioning device for tensioning the first handrail. The invention also relates to a method for detecting over-tension at the handrail of such an escalator. Background Technology
[0002] Escalators, used for transporting people and goods, are an integral part of modern residential and commercial buildings. A typical escalator includes a supporting structure, such as a welded frame, and steps, treads, or moving belts that provide the path. Thus, the steps, treads, or belts may be connected to or at least interconnected with the travel rails and are steered by two axes at the ends of the path. At least one axis may be a drive shaft, or may be connected to a drive shaft. The path guides upwards, flat, or ascending; the term escalator is understood to also include moving walkways.
[0003] Typically, escalators include devices to protect passengers from danger, such as handrails to prevent falls and handrails for safe gripping. The handrails are usually guided in a circular pattern parallel to the path so that there is no relative speed between the handrail and the components forming the path. Therefore, the handrails are made of rubber or similar materials, allowing them to turn at the ends of the escalator via steering columns. Due to the turning, the handrail bends, thus experiencing wear; if the tensioning device provides too much tension, this wear will increase. At the same time, a certain amount of tension is required for smooth operation of the handrail. While it is easy to detect under-tension during the initial commissioning of the escalator, it is difficult to detect over-tension. Therefore, technicians often accidentally set the tension too high, resulting in a shorter lifespan for the handrails. Summary of the Invention
[0004] In view of the above, the object of the present invention is to provide an escalator in which excessive tension in the handrail can be detected and / or prevented.
[0005] This objective is achieved through the features of the independent claim. Advantageous embodiments are indicated in the dependent claims. Where technically possible, the features of the dependent claims may be combined with features in the independent claim and / or other dependent claims as needed.
[0006] Specifically, this objective is achieved by an escalator comprising: a support structure; a plurality of steps or treads or a moving belt guided in a circular manner within the support structure and forming a path; at least one first handrail guided in a circular manner and turning around a first upper turning column and a first lower turning column respectively; at least one first tensioning device for tensioning the first handrail; at least one first temperature sensor disposed at the first handrail for measuring the temperature of the first handrail; at least one first reference temperature sensor for the first temperature sensor; and at least one processing unit configured to receive measured values from the first temperature sensor and the first reference temperature sensor; wherein the processing unit is configured to compare the measured value of the first temperature sensor with the measured value of the first reference temperature sensor.
[0007] Regarding the designation of elements by number, such as "first component," "second component," and "third component," this numbering is purely for differentiation in reference and does not indicate any dependency between elements or a mandatory order of elements. This specifically means, for example, that an apparatus or method does not necessarily need to have a "first component" in order to have a "second component." The apparatus may also include "first components" and "third components" without necessarily having a "second component." A single-numbered element may also have several units, such as several "first components."
[0008] According to this understanding, an escalator includes a path formed by steps, treads, or a moving belt supported by a support structure. Thus, one or more of the steps, treads, and conveyor belt are connected to or at least interconnected with a travel track, and are deflected at the ends of the path by two shafts. At least one shaft may be a drive shaft, or may be connected to a drive shaft. The escalator path may run upwards, downwards, or only horizontally to form an moving walkway, which is included in the term escalator.
[0009] As long as the handrail is guided in a circular manner on the escalator, it is fixed to a mounting bracket (e.g., partially formed by the escalator's railing) that moves along the circular track. Preferably, the upper part of the track is parallel to the path, such that people on the path reach the handrail in the same distance along the entire path. Furthermore, the handrail moves at the same speed along the circular track as one or more of the steps, treads, and belts moving along the path to avoid speed differences.
[0010] The tensioning device for the handrail can be integrated with one of the steering columns or separate from the steering column. Specifically, the tensioning device is formed by a wheel or another form of guide on which the handrail is turned. The wheel or other guide can be biased, thereby slightly lengthening or slightly shortening the track length. Therefore, if the tensioning device is integrated with one of the steering columns, that steering column can, for example, be biased.
[0011] The temperature of the handrail can be measured directly or indirectly, for example, at the surface of the handrail or through the temperature of a component in contact with the handrail (e.g., a steering column), provided a temperature sensor is provided to measure any other temperature at or around the escalator. This reference temperature sensor can be used in conjunction with the invention described below. In particular, the reference temperature sensor measures the ambient temperature or the temperature of another handrail.
[0012] The processing unit can be integrated with the central control unit of the escalator or it can be a separate unit. Furthermore, those skilled in the art will understand that means are provided for connecting temperature sensors to the processing unit, such as wires, and means for providing power voltage to the sensors, such as a power supply unit. Specifically, the escalator includes at least one gateway connected to the processing unit to serve as a power supply unit for sensor connection. Additionally, the escalator may include a conversion unit for parsing sensor data and providing the processing unit with a data format readable by the processing unit. Therefore, the conversion unit and / or the processing unit can acquire and process data through different communication protocols.
[0013] Comparing two values can include establishing a ratio between the two values or solving / verifying a mathematical equation or multiple mathematical equations that include the two values, each equation containing one value. This can be compared directly to a measured value or any suitable value derived from it.
[0014] The described escalator includes the following teaching: excessive tension in the handrail can be detected by comparing the handrail temperature with a reference temperature, thereby comparing the measurements of a first temperature sensor and a first reference temperature sensor. Excessive tension increases the bending work of the handrail, thus increasing wear and promoting aging and cracking. Therefore, the lifespan of the handrail is shortened. However, the increased bending work is converted into heat; therefore, under excessive tension, the heat input at the handrail increases, and the temperature is expected to be higher compared to a handrail without additional bending work. This difference can be detected by comparing the measurements of the first temperature sensor and the first reference temperature sensor using the previously described escalator. For example, the handrail temperature can be compared to the temperature of another handrail with lower tension, or to the ambient temperature, which is a major influencing factor on the handrail temperature. If an unexpected ratio is determined between the comparison values in either of these cases, this unexpected ratio can be interpreted as an indication of excessive tension in the corresponding handrail. Therefore, excessive tension can be detected, and measures can be taken to reduce the tension to prevent damage.
[0015] In one embodiment of the escalator, a first temperature sensor is disposed at a first upper steering column, and a second temperature sensor is disposed at a first lower steering column for measuring the temperature of the first handrail. A processing unit is configured to receive measurements from the second temperature sensor and to compare the measurements from the second temperature sensor with those from a first reference temperature sensor. By providing temperature sensors at the steering columns, these sensors are advantageously positioned near the areas where bending work and corresponding heat input occur. Therefore, the influence of heat input on temperature is highest in these areas, making them most easily detected. Furthermore, by disposing each of the first and second temperature sensors at one of the steering columns, a significant comparison can be made between the two drive directions of the escalator, as the drive side of the handrail changes with the drive direction, and the main heat input occurs at different steering columns. Additionally, the measurements from the two temperature sensors can be compared, or more specifically, the individual comparisons of the two temperature sensors with the reference temperature sensor can be compared to verify whether excessive tension should be interpreted from the respective measurements.
[0016] In another embodiment, the escalator includes: a first handrail located on a first side of the path and a second handrail located on a second side of the path, wherein the second handrail is guided in a circular manner and steers around a second upper steering column and a second lower steering column, respectively; a second tensioning device for tensioning the second handrail; a third temperature sensor disposed at the second handrail for measuring the temperature of the second handrail and a second reference temperature sensor for the third temperature sensor, wherein a processing unit is configured to receive measurements from the third temperature sensor and the second reference temperature sensor, wherein the processing unit is configured to compare the measurement value of the third temperature sensor with the measurement result of the second reference temperature sensor. Therefore, in this embodiment, the above teachings apply to both handrails of the escalator.
[0017] In the preferred configuration of the escalator described above, a third temperature sensor is located at the second upper steering column, and a fourth temperature sensor is located at the second lower steering column for measuring the temperature of the second handrail. A processing unit is configured to receive the measurement value from the fourth temperature sensor and to compare the measurement value of the fourth temperature sensor with the measurement value of a second reference temperature sensor. Therefore, the temperature sensors are again located at the steering columns, thus close to the area where bending work and corresponding heat input occur. Furthermore, by placing the third and fourth temperature sensors at one of the steering columns, a significant comparison can be made between the two drive directions of the escalator, as the drive side of the handrail changes with the drive direction, and the main heat input occurs at different steering columns. Additionally, the measurement values of the two temperature sensors can be compared, or more specifically, the individual comparisons of the two temperature sensors with the reference temperature sensor can be compared to verify whether the individual measurement values should be interpreted as excessive tension.
[0018] In another preferred configuration of the escalator as described above, the processing unit is configured to use a third or fourth temperature sensor as a first reference temperature sensor and / or use a first temperature sensor as a second reference temperature sensor. In this embodiment, the temperatures of the two handrails are compared. Since the tension is set separately at each handrail, it is unlikely that both handrails will experience over-tension at the same time and level. Therefore, the handrail with over-tension is likely to exhibit a higher temperature than the other handrail. Advantageously, since both handrails—besides the heat input from the potential over-tension—are affected by the same heat source and radiator in their environment, the measurements from the temperature sensor and the reference temperature sensor can be directly compared to detect over-tension.
[0019] In another preferred embodiment of the escalator, in conjunction with the foregoing embodiments, a first reference temperature sensor and / or a second reference temperature sensor are provided on the escalator to measure the ambient temperature. Since the environment, where the ambient temperature exists, is the primary heat source or radiator for the handrail, it can be assumed that under regular tension, at least in sufficiently approximate conditions, the handrail temperature is primarily a function of the ambient temperature and time. Therefore, when the ambient temperature changes, the handrail temperature will follow this change according to a certain time function, caused by the laws of heat transfer. Most advantageously, this is achieved by comparing the temperature of the corresponding handrail with the ambient temperature, a comparison independent of other heat sources or radiators that other components of the escalator may experience. In this embodiment, combined with the foregoing embodiments, two first reference sensors are provided, one on another handrail and one for measuring the ambient temperature, wherein the measured value of the corresponding temperature sensor is compared with the value of one or both first reference sensors.
[0020] In a particular configuration of the escalator embodiment described above, a first reference temperature sensor and / or a second reference temperature sensor are disposed on the comb plate or floor slab. Most preferably, the first reference temperature sensor and / or the second reference temperature sensor are disposed at the center of the comb plate or floor slab. In this location, the reference temperature sensor is placed furthest from other components of the escalator, thus allowing for the measurement of ambient temperature without interference from the temperature of other components. Furthermore, sufficient installation space is provided at the comb plate or floor slab.
[0021] In another configuration of the escalator embodiment described above, the first and second reference temperature sensors are configured as a single sensor. Since the ambient temperature is the same at both ends of the handrail and escalator, a single reference temperature sensor is sufficient to provide a reference measurement of the environment. Alternatively, two reference sensors can be provided, where the measurements from both sensors can be used for each comparison to achieve redundancy.
[0022] In a preferred embodiment of the escalator, the processing unit is configured to record the received measurements. Specifically, when comparing the measurements from the temperature sensor with those from a reference temperature sensor measuring the ambient temperature, the comparison depends on the value changing over time. Therefore, by recording the measurements, these changes over time can be compared to detect excessive tension.
[0023] In one embodiment of the escalator, at least one temperature sensor is a contact sensor and / or at least one sensor is an infrared sensor. These sensors allow for accurate temperature measurement without damaging the handrail. The handrail temperature can also be measured indirectly, for example, at the steering column or another component in direct contact with the handrail.
[0024] In another embodiment, the escalator includes: a first railing, wherein a first handrail is mounted on and guided on the first railing; and / or a second railing, wherein a second handrail is mounted on and guided on the second railing. In particular, upper and lower steering columns are incorporated into or mounted at the ends of the railing.
[0025] This objective is also achieved by a method for detecting excessive tension at the handrail of a pre-described escalator, the method comprising the steps of: receiving measurements from a first temperature sensor, a second temperature sensor, a third temperature sensor, and / or a fourth temperature sensor; receiving measurements from a first reference temperature sensor and / or a second reference temperature sensor; comparing the measurement from at least one temperature sensor with the measurement from its assigned reference temperature sensor; and indicating excessive tension in the corresponding handrail if an unexpected ratio is determined between the compared values.
[0026] The pre-described allocation of reference temperature sensors includes a first reference temperature sensor for the first temperature sensor and a second reference temperature sensor for the second temperature sensor, and a second reference temperature sensor for the third temperature sensor and a fourth temperature sensor. Indications of excessive tension force may include readable notifications in a protocol implemented in the processing unit, but may also include notifications to users, manufacturers, or technicians. Alarm notifications on escalators, such as those displayed on a monitor or audio alarm, may also be included.
[0027] The above method provides a simple way to detect over-tension in handrails, requiring only two sensors: a temperature sensor and a reference temperature sensor. This method is based on the teaching that additional heat input is generated on the handrail due to over-tension. Since the handrail is only affected by known / calculable heat sources and radiators, in addition to the heat input generated by the over-tension, the heat generated by the over-tension can be detected. This method can also be implemented according to pre-described embodiments of escalators. Specifically, to compare the temperatures of the two handrails, a third or fourth temperature sensor can be used as a first reference temperature sensor, and / or a first or second temperature sensor can be used as a second reference temperature sensor. Alternatively or additionally, a reference temperature sensor can be provided to measure the ambient temperature.
[0028] According to one embodiment of the method, at least one of the first, second, third, and fourth temperature sensors is used as a reference temperature sensor, wherein an unexpected ratio is determined because the measured values of the first and second handrails deviate from each other by more than a threshold. That is, since the handrails share the same environment and are affected by the same heat source and radiator in addition to potential over-tension, the handrails are expected to have similar temperatures, or at least small and constant deviations between their temperatures. Therefore, a deviation exceeding the corresponding threshold indicates over-tension on the handrail with the higher temperature.
[0029] According to another embodiment, the method further includes the step of recording measurements from at least one temperature sensor and its assigned reference temperature sensor over at least a first time period. By recording the measurements, time can be considered a variable in the comparison. Specifically, when the recorded measurements from the temperature sensors deviate from a predetermined function that uses the measurements from the assigned reference temperature sensor and time as variables, an unexpected proportion is determined. In particular, in the case where the reference temperature sensor measures the ambient temperature, the temperature of the handrail is expected to lag with changes in the ambient temperature, therefore time should be taken into account in the comparison. Attached Figure Description
[0030] In the following, preferred examples of embodiments are used to explain the invention in more detail with reference to the accompanying drawings. The term "drawings" is abbreviated as "Figures" in the drawings.
[0031] Figure 1a This is a perspective view of an escalator according to an embodiment of the present invention, wherein details are schematically shown; Figure 1b It is based on Figure 1a Detailed view of the end of the escalator and the steering column provided at the end for guiding the handrail; Figure 1c It is based on Figure 1a Detailed view of the floor slabs of the escalator; Figure 2 It is based on Figures 1a-1c A schematic diagram of the sensors, power supply unit, conversion unit, and processing unit of the escalator; and Figure 3 This is a schematic diagram of a method according to one aspect of the present invention. Detailed Implementation
[0032] The described embodiments are merely examples that can be modified and / or supplemented in various ways within the scope of the claims. Any feature described with respect to a particular embodiment may be used independently or in combination with other features in any other embodiment. Any feature described with respect to an embodiment of a particular class of claims may also be used accordingly in embodiments of another class of claims.
[0033] Figure 1a An escalator 1 is shown, having a support structure 2 and a plurality of steps 3 received and guided in a circular manner within the support structure 2. The steps form a path 4 that connects a lower floor slab 5.1 at a first height to an upper floor slab 5.2 at a second height. Furthermore, the escalator 1, mounted on the support structure 2, includes a first railing 6.1, a first handrail 7.1 mounted in a circular manner on and guided on the first railing 6.1; and a second railing 6.2, a second handrail 7.2 mounted in a circular manner on and guided on the second railing 6.2. Figure 1b The upper end of the second railing 6.2 is shown in detail, wherein the second handrail 7.2 turns back from the upper branch of the second railing into the skirt panel 8 of the escalator 1. To guide the second handrail 7.2 during the turn, a turning post 9 is installed on the second railing 6.2, on which the second handrail 7.2 is mounted / guided. The turning post 9 is made of metal and is in direct contact with the second handrail 7.2. Handrails 7.1 and 7.2 are based on... Figure 1b It is installed and guided at all ends of railings 6.1 and 6.2.
[0034] like Figure 1a As schematically shown, a first temperature sensor 11.1 is installed at the upper end of the first guardrail 6.1, i.e., at the first upper steering column 9.1, to measure the temperature of the first handrail 7.1 in the area of the first upper steering column 9.1. Furthermore, a second temperature sensor 11.2 is installed at the lower end of the first guardrail 6.1, i.e., at the first lower steering column 9.2, to measure the temperature of the first handrail 7.1 in the area of the first lower steering column 9.2. Similarly, a third temperature sensor 11.3 is installed at the upper end of the second guardrail 6.2, i.e., at the second upper steering column 9.3, to measure the temperature of the second handrail 7.2 in the area of the second upper steering column 9.3. Furthermore, a fourth temperature sensor 11.4 is installed at the lower end of the second guardrail 6.2, i.e., at the second lower steering column 9.4, to measure the temperature of the second handrail 7.2 in the area of the second lower steering column 9.4. Figure 1b The exemplary and illustrative third temperature sensor 11.3 shown is applicable to all temperature sensors 11.1, 11.2, 11.3, and 11.4. The sensor can be configured as an infrared sensor within the skirt panel 8, pointing towards the corresponding handrail 7.1, 7.2, or steering column 9.1, 9.2, 9.3, and 9.4. Alternatively, but not shown in detail, the temperature sensors 11.1, 11.2, 11.3, and 11.4 can be configured as contact sensors in contact with the steering columns 9.1, 9.3, 9.2, and 9.4 for indirect measurement, or in contact with the handrail 7.1 and 7.2 for direct measurement.
[0035] Figure 1c It shows that according to Figure 1a The upper floor slab 5.2 of the escalator 1 shows the topmost step 3 and the skirt panels 8 on both sides of the step 3. A reference temperature sensor 12 is provided on the upper floor slab to measure the ambient temperature of the escalator 1. The reference temperature sensor 12 serves simultaneously as a first reference temperature sensor 12.1 and a second reference temperature sensor 12.2.
[0036] Figure 2The circuitry for temperature sensors 11.1, 11.2, 11.3, 11.4, and reference temperature sensor 12 in an exemplary configuration is schematically shown. All these sensors 11.1, 11.2, 11.3, 11.4, and 12 are connected via wire 14 to a power supply unit 13, which is configured as a gateway. The power supply unit 13 provides power voltage to the sensors 11.1, 11.2, 11.3, 11.4, and 12, and receives signals from these sensors, such as analog signals. The power supply unit 13 is also connected to a conversion unit 15, which converts the signals into a data format readable by a processing unit 16. Therefore, the conversion unit 15 interprets the data from the sensors 11.1, 11.2, 11.3, 11.4, and 12 and provides it to the processing unit 16 in a data format readable by the processing unit 16. In the processing unit 16, operations can be performed according to… Figure 3 The processing unit 16 also includes a non-volatile memory 16.1 for recording values received from sensors 11.1, 11.2, 11.3, 11.4, and 12. The processing unit 16 may be the central control unit of the escalator 1.
[0037] Figure 3 It schematically shows the following based on Figures 1a to 1c A method 20 for detecting over-tension in one of the handrails 7.1 and 7.2 of an escalator 1. In a first step 21, a processing unit 16 receives measurements from a first temperature sensor 11.1, a second temperature sensor 11.2, a third temperature sensor 11.3, and / or a fourth temperature sensor 11.4. In a second step 22, the processing unit 16 receives measurements from a first reference temperature sensor 12.1 and / or a second reference temperature sensor 12.2. In a third step 23, the measurements of at least one temperature sensor 11.1, 11.2, 11.3, and 11.4, and their assigned reference temperature sensors 12.1 and 12.2, are recorded in a non-volatile memory 16.1 for at least a first time period. In a fourth step 24, the processing unit 16 compares the measurements of at least one temperature sensor 11.1, 11.2, 11.3, and 11.4 with their assigned reference temperature sensors 12.1 and 12.2. In step 5, 25, if the unexpected ratio between the comparison values is determined, the excessive tension in the corresponding handrails 7.1 and 7.2 is indicated.
[0038] List of reference numerals 1 Escalator 2 Support Structure 3 steps 4 paths 5.1 Lower floor slab 5.2 Upper floor slab 6.1 First railing 6.2 Second railing 7.1 First Handrail 7.2 Second Handrail 8 apron boards 9 steering columns 9.1 First upper steering column 9.2 First lower steering column 9.3 Second upper steering column 9.4 Second lower steering column 11.1 First Temperature Sensor 11.2 Second Temperature Sensor 11.3 Third Temperature Sensor 11.4 Fourth Temperature Sensor 12 Reference Temperature Sensors 12.1 First Reference Temperature Sensor 12.2 Second Reference Temperature Sensor 13 power supply units 14 conductors 15 conversion units 16 processing units 16.1 Non-volatile memory 20. Methods for detecting excessive tension in handrails The first step of method 21 is to receive the measurement value from the temperature sensor. The second step of method 22—receiving the measurement value from the reference temperature sensor. The third step of method 23—recording the measurements within the first time period. The fourth step of the 24 method—comparing the measured values The fifth step of the 25 method—indicating excessive tension.
Claims
1. An escalator (1) comprising: a support structure (2); a plurality of steps (3) or tread plates or moving belts guided in a loop-like manner in the support structure (2) and forming a path (4); at least one first handrail (7.1) guided in a loop-like manner and turned around a first upper turnaround column (9.1) and a first lower turnaround column (9.2), respectively; at least one first tensioning device for tensioning the first handrail (7.1); at least one first temperature sensor (11.1) provided at the first handrail (7.1) for measuring a temperature of the first handrail (7.1); at least one first reference temperature sensor (12.1) for the first temperature sensor (11.1); and at least one processing unit (16) configured to receive measurement values from the first temperature sensor (11.1) and the first reference temperature sensor (12.1); wherein the processing unit (16) is configured to compare the measurement values of the first temperature sensor (11.1) with the measurement values of the first reference temperature sensor (12.1).
2. The escalator (1) according to claim 1, wherein, the first temperature sensor (11.1) is provided at the first upper turnaround column (9.1); wherein a second temperature sensor (11.2) is provided at the first lower turnaround column (9.2) for measuring a temperature of the first handrail (7.1); wherein the processing unit (16) is configured to receive measurement values from the second temperature sensor (11.2); and wherein the processing unit (16) is configured to compare the measurement values of the second temperature sensor (11.2) with the measurement values of the first reference temperature sensor (12.1).
3. The escalator (1) according to claim 1 or 2, comprising: the first handrail (7.1) is located at a first side of the path (4) and the second handrail (7.2) is located at a second side of the path (4), wherein the second handrail is guided in a loop-like manner and turned around a second upper turnaround column (9.3) and a second lower turnaround column (9.4), respectively; a second tensioning device for tensioning the second handrail (7.2); a third temperature sensor (11.3) provided at the second handrail (7.2) for measuring a temperature of the second handrail (7.2); and a second reference temperature sensor (12.2) for the third temperature sensor (11.3); wherein the processing unit (16) is configured to receive measurement values from the third temperature sensor (11.3) and the second reference temperature sensor (12.2); wherein the processing unit (16) is configured to compare the measurement values of the third temperature sensor (11.3) with the measurement values of the second reference temperature sensor (12.2).
4. The escalator (1) according to claim 3, wherein the third temperature sensor (11.3) is provided at the second upper turnaround column (9.3); wherein a fourth temperature sensor (11.4) is arranged at the second lower swivel column (9.4) for measuring the temperature of the second handrail (7.2); wherein the processing unit (16) is configured to receive a measurement value from the fourth temperature sensor (11.4); and wherein the processing unit (16) is configured to compare the measurement value of the fourth temperature sensor (11.4) with the measurement value of the second reference temperature sensor (12.2).
5. Escalator (1) according to claim 3 or 4, wherein The processing unit (16) is configured to use the third temperature sensor (11.3) or the fourth temperature sensor (11.4) as the first reference temperature sensor (12.1) and / or to use the first temperature sensor (11.1) or the second temperature sensor (11.2) as the second reference temperature sensor (12.2).
6. Escalator (1) according to any of the preceding claims, wherein The first reference temperature sensor (12.1) and / or the second reference temperature sensor (12.2) is arranged at the escalator (1) for measuring an ambient temperature.
7. Escalator (1) according to claim 6, wherein The first reference temperature sensor (12.1) and / or the second reference temperature sensor (12.2) is arranged at a comb plate or a floor plate (5.1, 5.2).
8. Escalator (1) according to claim 6 or 7, wherein The first reference temperature sensor (12.1) and the second reference temperature sensor (12.2) are arranged as a single sensor (12).
9. Escalator (1) according to any of the preceding claims, wherein The processing unit (16) is configured to record the received measurement values.
10. Escalator (1) according to any of the preceding claims, wherein At least one temperature sensor (11.1, 11.2, 11.3, 11.4) is a contact sensor and / or at least one temperature sensor (11.1, 11.2, 11.3, 11.4) is an infrared sensor.
11. Escalator (1) according to any one of the preceding claims, comprising first balustrade (6.1), wherein The first handrail (7.1) is mounted on and guided on the first balustrade (6.1); and / or a second balustrade (6.2), wherein the second handrail (7.2) is mounted on and guided on the second balustrade (6.2).
12. A method (20) for detecting an excessive tension force at a handrail (7.1, 7.2) of an escalator (1) according to any one of the preceding claims, the method (20) comprising the steps of: receiving a measurement value (21) of the first temperature sensor (11.1), the second temperature sensor (11.2), the third temperature sensor (11.3) and / or the fourth temperature sensor (11.4); receiving a measurement value (22) of the first reference temperature sensor (12.1) and / or the second reference temperature sensor (12.2); comparing (24) the measurement value of at least one temperature sensor (11.1, 11.2, 11.3, 11.4) with the measurement value of its assigned reference temperature sensor (12.1, 12.2); and in case of determining an unexpected proportion between the comparison values, prompting an excessive tension force (25) in the respective handrail (7.1, 7.2).
13. The method (20) of claim 12, wherein, At least one of the first temperature sensor (11.1), the second temperature sensor (11.2), the third temperature sensor (11.3) and the fourth temperature sensor (11.4) is used as a reference temperature sensor (12), wherein an unexpected proportion is determined, which consists in that the measured values of the first handrail (7.1) and the second handrail (7.2) deviate from each other beyond a threshold value.
14. The method (20) according to claim 12 or 13, further comprising the steps of: recording the measured values (23) of at least one temperature sensor (11.1, 11.2, 11.3, 11.4) and its assigned reference temperature sensor (12.1, 12.2) over at least a first time period.
15. The method (20) of claim 14, wherein, determining an unexpected proportion when the recorded measured values of the temperature sensor (11.1, 11.2, 11.3, 11.4) deviate from a predetermined function in terms of the measured values of the assigned reference temperature sensor (12.1, 12.2) and time.