System and method for measuring tension member elongation
By using a combination of weight sensors, car sensors and machine pulley encoder in the elevator system, the accuracy and repetition of the elongation measurement of suspension components is solved, and automated elongation monitoring and replacement reminders are realized.
Patent Information
- Application Number
- CN202411428774.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2023-10-23
- Filing Date
- 2024-10-14
- Publication Date
- 2025-04-25
AI Technical Summary
During the process of measuring the elongation of a suspended component, it is difficult for the prior art to detect very small scale changes in elongation repeatedly and accurately.
A system is adopted that includes suspension components, machine pulleys, load-to-weight sensors, car sensors, encoders and control systems. By recording the travel amount for the triggering of the load sensor and the car sensor, the travel amount of the suspension member is determined by using the travel amount of the machine pulley.
Accurate measurement and tracking of the elongation of the suspension component is achieved, and the measurement can be performed regularly without mechanic intervention and automatically generate a replacement indication signal when predetermined conditions are met.
Smart Images
Figure CN119873543A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to systems and methods for measuring the elongation of a tension member. Background Art
[0002] For example, elevator systems are widely used to transport passengers between levels in buildings. Some elevator systems are based on traction, where a suspension assembly (sometimes referred to as a sling) suspends the elevator car and counterweight. The suspension assembly also facilitates the movement of the elevator car when needed. Traditional suspension assemblies include round steel ropes. Some elevator systems include other types of suspension components, such as flat belts or other types of ropes, which have tension members enclosed in a compressible polymer sheath. The elongation of the suspension components (especially coated suspension components) is an indicator of the life / retained breaking strength. Because the elongation occurs on a very small scale, it may be challenging to measure repeatedly and accurately. Summary of the invention
[0003] An illustrative exemplary elevator system includes: at least one suspension component that supports an elevator car and facilitates movement of the elevator car in a hoistway; a machine pulley that supports the at least one suspension component; a counterweight that is coupled to the elevator car using the at least one suspension component; a counterweight sensor that detects the presence of the counterweight; a car sensor that detects the presence of the elevator car; an encoder that begins determining travel distance once one of the counterweight sensor or the car sensor is triggered; and a control system that generates a control signal to use the encoder to determine the amount of travel of the elevator car that occurs between triggering one of the counterweight sensor and the car sensor and triggering the other of the counterweight sensor and the car sensor.
[0004] In addition to, or as an alternative to, one or more of the features described above, the counterweight sensor comprises a single discrete sensor positioned at a fixed position in the hoistway.
[0005] In addition to or as an alternative to one or more of the features described above, the single discrete sensor includes a limit switch, a photoelectric sensor, or a proximity sensor positioned on the counterweight side of the hoistway.
[0006] In addition to or in the alternative to one or more of the features described above, the car sensor comprises a single discrete sensor positioned at a fixed location in the hoistway.
[0007] In addition to or as an alternative to one or more of the features described above, the single discrete sensor includes an extreme limit switch, a photoelectric sensor, or a proximity sensor positioned on the car side of the hoistway.
[0008] In addition to or as an alternative to one or more of the features described above, the car sensor includes a door landing zone sensor.
[0009] In addition to or alternatively to one or more of the features described above, the encoder includes a machine encoder associated with a machine pulley and wherein the amount of travel is recorded between triggering of one of the counterweight sensor and the car sensor and triggering of the other of the counterweight sensor and the car sensor.
[0010] In addition to or in the alternative to one or more of the features described above, the encoder comprises a car encoder associated with an elevator car.
[0011] Additionally or alternatively to one or more of the features described above, the distance between the counterweight sensor and the car sensor remains fixed.
[0012] In addition to or as an alternative to one or more of the features described above, a control signal is generated only if the elevator car is empty and traveling at a constant speed between triggering of one of the counterweight sensor and the car sensor and triggering of the other of the counterweight sensor and the car sensor.
[0013] Additionally or alternatively to one or more of the features described above, the control system monitors the amount of travel over time to determine elongation of at least one suspension component and generates an indication signal when one or more predetermined conditions are met indicating that the at least one suspension component should be replaced.
[0014] In addition to or as an alternative to one or more of the features described above, when the elevator car travels downward, the counterweight sensor first detects the presence of the counterweight and then the car sensor detects the presence of the elevator car, or the car sensor first detects the presence of the elevator car and then the counterweight sensor detects the presence of the counterweight.
[0015] In addition to one or more of the features described above, or as an alternative, when the elevator car travels upward, the counterweight sensor first detects the presence of the counterweight and then the car sensor detects the presence of the elevator car, or the car sensor first detects the presence of the elevator car and then the counterweight sensor detects the presence of the counterweight.
[0016] An illustrative exemplary method includes an elevator car supported by at least one suspension member for movement within a hoistway, a counterweight coupled to the elevator car by the at least one suspension member, and the at least one suspension member supported on a machine pulley at a location between the elevator car and the counterweight, the method further comprising: detecting the presence of one of the counterweight or the elevator car as an initial detection; subsequently detecting the presence of the other of the counterweight or the elevator car as a subsequent detection; and determining an amount of travel of the elevator car that occurs between the initial detection and the subsequent detection to determine an amount of extension of the at least one suspension member.
[0017] In addition to or alternatively to one or more of the features described above, the method further comprises positioning a single discrete sensor at a fixed location in the hoistway to detect the presence of a counterweight, and positioning a single discrete sensor at a fixed location in the hoistway to detect the presence of an elevator car.
[0018] Additionally or alternatively to one or more of the features described above, the method further comprises providing a machine encoder associated with the machine pulley, and recording an amount of travel of the machine pulley between an initial detection and a subsequent detection.
[0019] Additionally or alternatively to one or more of the features described above, the method further includes providing a car encoder associated with the elevator car, and determining an amount of travel of the elevator car between an initial detection and a subsequent detection.
[0020] In addition to or alternatively to one or more of the features described above, the method also includes monitoring the amount of travel over time to determine elongation of at least one suspension component, and generating an indication signal to indicate that the at least one suspension component should be replaced when one or more predetermined conditions are met.
[0021] In addition to or as an alternative to one or more of the features described above, the method comprises, when the elevator car is travelling downwards, first detecting the presence of a counterweight and then detecting the presence of the elevator car; or first detecting the presence of the elevator car and then detecting the presence of the counterweight.
[0022] In addition to or as an alternative to one or more of the features described above, when the elevator car is travelling upwards, the method comprises: first detecting the presence of a counterweight and then detecting the presence of the elevator car; or first detecting the presence of the elevator car and then detecting the presence of the counterweight.
[0023] The various features and advantages of the exemplary embodiments will become apparent to those skilled in the art from the following detailed description.The drawings that accompany the detailed description can be briefly described as follows. BRIEF DESCRIPTION OF THE DRAWINGS
[0024] Figure 1 Selected portions of an elevator system incorporating the measurement system of the present disclosure are schematically shown in a first position.
[0025] Figure 2 Selected portions of an elevator system incorporating the measurement system of the present disclosure are schematically shown in a second position.
[0026] Figure 3 is a flow chart describing a method of monitoring tension components in an elevator system. DETAILED DESCRIPTION
[0027] Embodiments of the present disclosure provide a simple and cost-effective system and method for measuring the elongation of a suspension component.
[0028] Figure 1 Selected portions of an elevator system 20 are schematically shown. An elevator car 22 is supported by a roping arrangement or suspension assembly 24 that includes one or more suspension members 26. The elevator car 22 is coupled to a counterweight 28 by the suspension members 26. In one example, the suspension members 26 include coated ropes or coated steel belts with tension members enclosed in a compressible polymer jacket.
[0029] The machine pulley 30 is associated with a machine encoder 32. The machine pulley 30 facilitates movement of the elevator car 22 within a hoistway 34. The elevator car 22 and the counterweight 28 move vertically when the suspension member 26 moves in response to the rotation of the machine pulley 30. The suspension member 26 may move about additional pulleys (not shown) when the elevator car 22 moves between landings or levels.
[0030] In one example, a machine pulley 30 supports a suspension member 26 at a location between a counterweight 28 and an elevator car 22. The measurement system includes at least a first sensor 36 that detects the presence of the counterweight 28 and a second sensor 38 that detects the presence of the elevator car 22. The control system includes a driver / controller 42 that generates a control signal to use the encoder 32 to record the amount of travel between the triggering of the first sensor 36 and the triggering of the second sensor 38.
[0031] In one example, the first sensor 36 includes a single discrete sensor positioned at a fixed position 44 in the hoistway 34. In one example, the single discrete sensor is positioned on the counterweight side of the hoistway 34. In one example, the single discrete sensor includes an extreme switch, a photoelectric sensor, a proximity sensor, or a similar sensing device; however, other types of detection sensors may also be used. In one example, the second sensor 38 includes a single discrete sensor positioned at a fixed position 46 in the hoistway 34. In one example, the single discrete sensor is positioned on the car side of the hoistway 34. In one example, the single discrete sensor includes an extreme switch, a photoelectric sensor, a proximity sensor, or a similar sensing device; however, other types of detection sensors may also be used. In one example, the sensor 38 includes a door landing zone sensor. The door landing zone sensor is an existing sensor used to determine when the elevator car arrives at the associated landing. The positions of the first sensor 36 and the second sensor 38 remain unchanged, so that the distance between the sensors 36 and 38 remains fixed and constant.
[0032] In one example, the encoder includes a machine encoder 32 associated with the machine pulley 30. Based on the fixed dimensions of the machine components, the machine encoder 32 records the travel between the triggering of the first sensor 36 and the triggering of the second sensor 38, and the linear distance traveled can be calculated.
[0033] In one example, the first sensor 36 is to be placed in a position so that the first sensor 36 detects the presence of the counterweight 28 when the elevator car 22 approaches the second sensor 38 from a given direction (event 1). The direction of the car motion during this period may be upward or downward depending on the relative positioning of the sensor 36 and the sensor 38. In one example, the second sensor 38 is an existing door landing zone sensor, the designated floor is the lobby, and the given direction is downward.
[0034] Once the first sensor 36 is triggered, the driver / controller 42 causes the travel of the machine pulley 30 to be recorded via the machine encoder 32 until the second sensor 38 is reached (Event 2). The travel of the machine pulley 30 is proportional to the distance A traveled by the elevator car 22 between triggering the first sensor 36 and triggering the second sensor 38. As the suspension member 26 stretches over time, this distance A will decrease in proportion to the elongation; therefore, the change in the travel of the machine pulley 30 between Event 1 and Event 2 is proportional to the elongation of the suspension member 26. Therefore, as the distance A decreases, the travel of the machine pulley 30 will decrease proportionally.
[0035] While the example shows the use of a machine encoder 32, the encoder may be positioned / configured in a variety of ways where the purpose is simply to have the ability to record distance traveled. In an alternative configuration, the encoder may include a car-mounted encoder 50 associated with the elevator car 22. In this example, the amount of travel is recorded between the triggering of the first sensor 36 and the triggering of the second sensor 38 via the car encoder 50.
[0036] While the example includes a first sensor 36 positioned on the counterweight side of the hoistway 34 and a second sensor 38 positioned on the car side of the hoistway 34, the order of inputs from the sensors may be reversed. In an alternative configuration, the first sensor 38 is on the car side of the hoistway 34 and the second sensor 36 is on the counterweight side of the hoistway 34. As previously mentioned, the direction of car motion during an "event" may be upward or downward. As a result, the method can be used in four sensor / motion arrangements: (1) the elevator car 22 travels downward, where sensor 36 first detects the presence of counterweight 28, followed by sensor 38 detecting the presence of elevator car 22; (2) the elevator car 22 travels upward, where sensor 36 first detects the presence of counterweight 28, followed by sensor 38 detecting the presence of elevator car 22; (3) the elevator car 22 travels downward, where sensor 38 first detects the presence of elevator car 22, followed by sensor 36 detecting the presence of counterweight 28; or (4) the elevator car 22 travels upward, where sensor 38 first detects the presence of elevator car 22, followed by sensor 36 detecting the presence of counterweight 28.
[0037] The driver / controller 42 is part of the control system and includes one or more processors that are used to initiate the recording of the travel of the pulley, receive input from the sensors 36, 38, and determine the elongation-based data generated by the encoder. In one example, the processor includes one or more computing devices and associated memory. The processor is programmed or otherwise configured to use different types of information to quantify the proportional relationship between the change in travel of the machine pulley over time and the elongation of the suspension component 26 between event 1 and event 2.
[0038] In one example, to minimize errors, the drive / controller 42 will cause measurements to occur only if the load load cell 52 detects a certain load condition, such as an empty elevator car 22, and if the elevator car 22 is traveling at a constant speed. The determination of speed may be made via known motion control parameters or via input from existing elevator system sensors, including existing encoders. Measuring only under these conditions allows the measurements to be unaffected by possible anomalies in car loading and speed, both of which may affect the forces acting on the suspension components and therefore the amount of extension experienced by the suspension components.
[0039] like Figure 3 As shown in FIG. 1 , the subject disclosure proposes a method for automatically measuring and tracking the elongation of a suspension component over its service life. First, a sensor detects the presence of one of the counterweight or elevator car from a given direction, as shown at 100 (event 1), to provide an initial detection. Once event 1 is triggered, it triggers the recording of the travel amount T ( Figure 2) steps, such as R1( Figure 1 ). Subsequently, another sensor detects the presence of the other of the counterweight or elevator car, as indicated at 200 (Event 2), to provide subsequent detection. Once Event 2 is triggered, the recording of the travel amount is stopped, as indicated at R2 ( Figure 2 ) is indicated at . Next, determine the travel distance T ( Figure 2 ), as indicated at 300. The travel of the machine pulley during this period is proportional to the distance the car travels between triggering of the sensors (i.e., distance A). As the suspension components stretch over time, this distance A will decrease in proportion to the elongation; thus, the change in travel of the machine pulley is proportional to the elongation of the suspension components. Thus, elongation can be determined based on the changing amount of travel over time, as indicated at 400.
[0040] The subject disclosure proposes a method of measuring and tracking elongation without adding expensive measuring devices, but rather by utilizing the high resolution available from an encoder (such as a machine encoder) combined with two inexpensive discrete sensors (one or more of which may be existing within the hoistway, such as existing door zone sensors). Since the drive / controller performs this function, the measurement can be performed regularly without mechanic intervention. The elongation can be monitored remotely, and when one or more predetermined conditions are met, an alarm or indication signal can be automatically generated so that the suspension component can be replaced as needed. Those skilled in the art, having the benefit of this description, will be able to determine the one or more predetermined conditions to be applied for these purposes.
[0041] The foregoing description is exemplary rather than limiting in nature. Variations and modifications to the disclosed examples may become apparent to those skilled in the art that do not necessarily depart from the essence of the invention. The scope of legal protection afforded this invention can only be determined by studying the claims.
Claims
1. An elevator system, comprising: at least one suspension member that supports the elevator car and facilitates movement of the elevator car in the hoistway; a machine pulley supporting the at least one suspension member; a counterweight coupled to the elevator car using the at least one suspension member; a counterweight sensor, the counterweight sensor detecting the presence of the counterweight; a car sensor, the car sensor detecting the presence of the elevator car; an encoder that begins determining distance traveled once one of the counterweight sensor or the car sensor is triggered; as well as A control system generates a control signal to use the encoder to determine an amount of travel of the elevator car that occurs between triggering one of the counterweight sensor and the car sensor and triggering the other of the counterweight sensor and the car sensor.
2. The elevator system according to claim 1, wherein: The counterweight sensor comprises a single discrete sensor positioned at a fixed location in the hoistway.
3. The elevator system according to claim 2, wherein: The single discrete sensor comprises a limit switch, a photoelectric sensor, or a proximity sensor positioned on the counterweight side of the hoistway.
4. The elevator system according to claim 1, wherein: The car sensor comprises a single discrete sensor positioned at a fixed location in the hoistway.
5. The elevator system according to claim 4, wherein: The single discrete sensor includes a limit switch, a photoelectric sensor, or a proximity sensor positioned on the car side of the hoistway.
6. The elevator system according to claim 1, wherein: The car sensor includes a door landing area sensor.
7. The elevator system according to claim 1, wherein: The encoder includes a machine encoder associated with the machine pulley, and wherein travel is recorded between triggering of one of the counterweight sensor and the car sensor and triggering of the other of the counterweight sensor and the car sensor.
8. The elevator system according to claim 1, wherein: The encoder includes a car encoder associated with the elevator car.
9. The elevator system according to claim 1, wherein: The distance between the counterweight sensor and the car sensor remains fixed.
10. The elevator system according to claim 1, wherein: The control signal is generated only if the elevator car is empty and traveling at a constant speed between triggering of one of the counterweight sensor and the car sensor and triggering of the other of the counterweight sensor and the car sensor.
11. The elevator system according to claim 1, wherein: The control system monitors the amount of travel over time to determine elongation of the at least one suspension component and generates an indication signal when one or more predetermined conditions are met indicating that the at least one suspension component should be replaced.
12. The elevator system according to claim 1, wherein: When the elevator car travels downward, the counterweight sensor first detects the presence of the counterweight and then the car sensor detects the presence of the elevator car, or the car sensor first detects the presence of the elevator car and then the counterweight sensor detects the presence of the counterweight.
13. The elevator system according to claim 1, wherein: When the elevator car travels upward, the counterweight sensor first detects the presence of the counterweight and then the car sensor detects the presence of the elevator car, or the car sensor first detects the presence of the elevator car and then the counterweight sensor detects the presence of the counterweight.
14. A method, wherein: An elevator car is supported by at least one suspension member for movement within a hoistway, a counterweight is coupled to the elevator car using the at least one suspension member, and the at least one suspension member is supported on a machine pulley at a location between the elevator car and the counterweight, the method comprising: detecting the presence of one of the counterweight or the elevator car as an initial detection; subsequently detecting the presence of the other of the counterweight or the elevator car as a subsequent detection; and An amount of travel of the elevator car that occurs between the initial detection and the subsequent detection is determined to determine an amount of extension of the at least one suspension member.
15. The method of claim 14, comprising positioning a single discrete sensor at a fixed location in the hoistway to detect the presence of the counterweight, and positioning a single discrete sensor at a fixed location in the hoistway to detect the presence of the elevator car.
16. The method of claim 14 including providing a machine encoder associated with said machine pulley and recording the amount of travel of said machine pulley between said initial detection and said subsequent detection.
17. The method of claim 14, comprising providing a car encoder associated with the elevator car and determining an amount of travel of the elevator car between the initial detection and the subsequent detection.
18. The method of claim 14, comprising monitoring the amount of travel over time to determine elongation of the at least one suspension component, and generating an indication signal to indicate that the at least one suspension component should be replaced when one or more predetermined conditions are met.
19. The method according to claim 14, wherein: When the elevator car is traveling downward, the method comprises: Firstly detecting the presence of the counterweight and subsequently detecting the presence of the elevator car; or First the presence of the elevator car is detected, followed by the presence of the counterweight.
20. The method according to claim 14, wherein: When the elevator car is traveling upward, the method comprises: Firstly detecting the presence of the counterweight and subsequently detecting the presence of the elevator car; or First the presence of the elevator car is detected, followed by the presence of the counterweight.