Elevator system with improved stopping accuracy

Abstract

According to the present invention, an elevator system is provided in which an elevator car is capable of moving between two adjacent floors of a building using a traction pulley drive in an elevator shaft, wherein an elevator control unit for moving the elevator car from one floor to another floor controls the traction pulley drive by means of a control signal using a value of the traction pulley diameter, and the elevator control unit is further designed to: after the initial configuration of the elevator system, control iterative adjustments to the value of the traction pulley diameter used to determine the control signal in order to improve the stopping accuracy of the elevator car.

Description

Technical Field

[0001] This invention relates to an elevator system with improved stopping accuracy. Background Technology

[0002] Elevator systems for transporting people from one floor of a building to another are known. These elevator systems have a car positioned in an elevator shaft and attached to at least one suspension rope, which is driven by a drive unit and connected, for example via an idler pulley, to a counterweight located at the other end of the suspension rope.

[0003] The drive unit has a driver, for example an electric motor, configured to drive a traction pulley. The traction pulley has teeth on its outer circumference that engage with corresponding teeth on the suspension rope for conveying the suspension rope.

[0004] The movement of the elevator car from one floor to another in a building is controlled by an elevator control unit located in a machine room. This machine room may also contain the drive unit and idler pulleys for suspending the ropes.

[0005] The elevator control unit is connected to a device for determining the car's position, which provides the elevator control unit with data containing information about the current car position. The elevator control unit receives this data, evaluates it, and provides control commands for elevator operation, specifically control signals for the elevator system's drive unit.

[0006] The elevator control unit is a computer unit equipped with a memory that stores operating programs. These programs are pre-created based on predetermined characteristic data of the elevator system, and the elevator control unit uses these programs to determine the control signals required during operation. This characteristic data includes information about the length and material properties of the suspension ropes, the height and weight of the elevator car, the diameter of the traction pulley, and other information. Furthermore, specified characteristics include information about the elevator car's travel speed and the time required for the elevator car to move from one floor to another.

[0007] If the building containing the elevator system has more than two floors, the device used to determine the car's position has a so-called absolute positioning system. To achieve this, a code marker pattern and a sensor device are necessary. The code marker pattern is placed along the entire travel distance of the elevator car in the elevator shaft and consists of multiple code markers. Each of these code markers contains a digital code representing the absolute position of the elevator car relative to a reference point in the elevator shaft. The sensor device is attached to the elevator car and scans the code markers non-contactly while the elevator car is moving to provide the elevator control unit with information about the current absolute position of the elevator car.

[0008] However, the installation of such an absolute positioning system involves a significant amount of work and is therefore associated with considerably high installation costs. Summary of the Invention

[0009] The purpose of this invention is to provide a simple and inexpensive method for improving the stopping accuracy of an elevator car at a target floor for a simple elevator system in which the car only needs to move between two floors.

[0010] This objective is achieved by an elevator system having the features indicated in claim 1. Advantageous embodiments and further developments of the invention are given in dependent claims 2 to 15.

[0011] According to the present invention, an elevator system is provided in which an elevator car is capable of moving between two adjacent floors of a building using a traction pulley drive in an elevator shaft, wherein an elevator control unit for moving the elevator car from one floor to another floor controls the traction pulley drive by means of a control signal determined using a stored value of the traction pulley diameter, the elevator control unit being further designed to: after the initial configuration of the elevator system, control iterative adjustments to the value of the traction pulley diameter used to determine the control signal in order to improve the stopping accuracy of the elevator car.

[0012] The advantages of this invention include, in particular, the fact that it eliminates the need for a costly, installation-intensive absolute positioning system to ensure that the elevator car stops at a predefined stopping area during normal operation of the elevator system (i.e., during the transport of people from one floor of a building to a corresponding adjacent floor), and does not stop before or after the initial stop. Specifically, for the implementation of this invention, it eliminates the need for a code-marking pattern consisting of multiple code marks applied along the entire travel path of the elevator car, each code mark containing a digital code of the absolute position of the elevator car relative to a reference point in the elevator shaft. To implement this invention, only two position markers of predetermined length are required, one assigned to the first floor of the building and a second assigned to the second floor of the building. Neither of these position markers requires digital encoding of the absolute position of the elevator car. Attached Figure Description

[0013] Other advantageous features of the invention may be seen from the following exemplary explanation of the invention with reference to the accompanying drawings.

[0014] Figure 1 A block diagram of an elevator system with an elevator car capable of moving between two floors of a two-story building is shown.

[0015] Figure 2 A flowchart illustrating a method for improving the stopping accuracy of an elevator car is shown. Detailed Implementation

[0016] Figure 1 A block diagram of an elevator system 10 is shown, which has an elevator car 1 capable of moving between two floors 40.1 and 40.2 of a two-story building 40.

[0017] In this elevator system 10, the elevator car 1 and the counterweight 2 are suspended from opposite ends of the suspension rope 3 in the elevator shaft 4 of the building 40. The suspension rope 3 crosses the idler sheave 5 and is driven by the drive unit 6.2 via the traction pulley 6.1. The traction pulley 6.1 and the drive unit 6.2 form the traction pulley drive 6. Figure 1 In the illustrated embodiment, the traction pulley drive 6, along with the idler wheel 5 and the elevator control unit 11, is positioned in a separate machine room 4a. In the example embodiment shown, the machine room 4a is located above the elevator shaft 4. However, the traction pulley drive 6, idler wheel 5, and elevator control unit 11 may also be located directly within the elevator shaft 4.

[0018] By turning the traction pulley 6.1 to the left or right, the elevator car 1 moves along the travel path in or against the direction y, and serves the two floors 40.1 and 40.2 of the building 40.

[0019] An apparatus 8 for determining the position of an elevator car is provided, the apparatus 8 including a sensor device 8.1 and an evaluation unit 8.2. The sensor device 8.1 and the evaluation unit 8.2 are attached to and move with the elevator car 1. During the movement of the elevator car 1, the sensor device 8.1 detects position markers 9.1 and 9.2 attached to the elevator shaft 4, wherein position marker 9.1 is assigned to floor 40.1 and position marker 9.2 is assigned to floor 40.2.

[0020] exist Figure 1In the example shown, sensor device 8.1 and evaluation unit 8.2 are mounted on the top of elevator car 1. Position markers 9.1 and 9.2 each have a predetermined length in the direction of travel, for example, 20 cm. The central area of ​​position markers 9.1 and 9.2 in the direction of travel is attached to a height position in elevator shaft 4 where sensor device 8.1 is located when elevator car 1 reaches a predetermined stopping area for the corresponding target floor. If elevator car 1 does not stop precisely in the predetermined stopping area after its journey, but is higher or lower than the predetermined stopping area, sensor device 8.1 is located, for example, in the upper or lower edge area of ​​the corresponding position marker, which can be detected by evaluation unit 8.2 or elevator control unit 11. Evaluation unit 8.2 converts the sensor signal provided by sensor device 8.1 into a data format suitable for use by elevator control unit 11 and forwards this data to elevator control unit 11 via suspension cable 7. The elevator control unit 11 uses this data to provide control commands necessary for the operation of the elevator car according to a predetermined working procedure, such as control commands for the traction pulley drive of the elevator system.

[0021] exist Figure 1 During the installation of the elevator system shown, the memory associated with the elevator control unit 11 is filled with data required by the elevator control unit during the operation of the elevator system. This data includes operating procedures and characteristic data describing the various properties of the various components of the elevator system. These characteristic data specifically include information about the length and material properties of the suspension rope 3, the height and weight of the elevator car 1, and the diameter of the traction pulley. Furthermore, specified characteristic data includes information about the elevator car's travel speed and the time required for the elevator car to travel from one floor to another.

[0022] During elevator system operation, the elevator control unit uses data stored in memory, along with other information, to provide control signals to the traction pulley drive 6. These signals cause the traction pulley 6.1 to rotate in the desired direction, thus moving the elevator car 1 from one floor to another. In practice, using data stored in memory often fails to achieve the required stopping accuracy of the elevator car within the predetermined stopping area of ​​the target floor. This is due to imprecise manufacturing and assembly of elevator system components. Therefore, to achieve the necessary stopping accuracy, additional measures are required to improve the stopping accuracy based on the original data stored in memory to ensure the desired stopping accuracy within the predetermined stopping area.

[0023] According to the present invention, this is achieved by an elevator control unit 11, which is designed to control the iterative adaptation of the value of the traction pulley diameter used to determine the control signal, using data stored in a memory after the initial configuration of the elevator system 10 has been performed, in order to improve the stopping accuracy of the elevator car 1.

[0024] The following is for reference. Figure 2 To explain this, Figure 2 A flowchart illustrating a method for improving the stopping accuracy of an elevator car is shown.

[0025] In step S1, the aforementioned initial configuration of the elevator system is performed, wherein the data mentioned above is stored in the memory of the elevator control unit 11.

[0026] The data includes a predetermined value for the diameter of the traction pulley 6.1, as well as other information, which is used by the elevator control unit 11 in the subsequent step S2 to provide a control signal for the traction pulley drive 6, which causes the traction pulley 6.1 to rotate so that the elevator car moves from one floor to an adjacent floor.

[0027] Then, in step S3, the information about the position of the elevator car provided by the device 8 for determining the car position is evaluated to check whether the elevator car has stopped in the predetermined stopping area of ​​the target floor.

[0028] If the elevator car has already stopped in the predetermined stopping area of ​​the target floor, the system proceeds to step S4.

[0029] In step S4, it is confirmed that the elevator car has stopped in the predetermined stopping area, and it is determined that no adjustment is needed to the value of the traction pulley diameter.

[0030] The process transitions from step S4 to step S5, where the adjustment procedure is completed.

[0031] On the other hand, if it is determined in step S3 that the elevator car has not stopped in the predetermined stopping area, then proceed to step S6.

[0032] In step S6, an inspection is performed to determine whether the elevator car has moved beyond the predetermined stopping area.

[0033] If it is detected in step S6 that the elevator car has moved beyond the predetermined stopping area, the process proceeds to step S7. In step S7, the value specified for the traction pulley diameter is reduced by a predetermined amount. This predetermined amount depends on the length of the position marker and, for example, corresponds to half the length of the position marker. This changed value of the traction pulley diameter is stored in memory, replacing the original stored value of the traction pulley diameter.

[0034] Returning from step S7 to step S2, in which the elevator control unit 11 now provides a modified control signal to the traction pulley drive 6, the modified control signal being determined by a reduced value for the traction pulley diameter. With the aid of this modified control signal, the elevator car moves again between the two floors of the building.

[0035] Following this, the next step is step S3, in which the information about the position of the elevator car provided by the device 8 for determining the car position is evaluated to determine whether the elevator car has stopped in the predetermined stopping area of ​​the target floor.

[0036] If the elevator car has already stopped in the predetermined stopping area of ​​the target floor, the system proceeds to step S4.

[0037] In step S4, it is confirmed that the elevator car has stopped in the predetermined stopping area and that no further adjustment of the traction pulley diameter is required.

[0038] Step S4 is followed by step S5, which ends the adjustment process.

[0039] On the other hand, if it is determined in step S3 that the elevator car does not stop in the predetermined stopping area even when the reduced value of the traction pulley diameter is applied, then proceed to step S6 again.

[0040] In step S6, an inspection is performed to determine whether the elevator car has moved beyond the predetermined stopping area.

[0041] If it is detected in step S6 that the elevator car has moved beyond the predetermined stopping area, the process proceeds to step S7 again. In step S7, a further reduction in the value specified for the traction pulley diameter occurs. This reduction again depends on the length of the position marker and, for example, corresponds to one-quarter of the length of the position marker. The changed value of the traction pulley diameter is stored in memory, replacing the previously stored value of the traction pulley diameter.

[0042] Returning from step S7 to step S2, in which the elevator control unit 11 provides another modified control signal to the traction pulley drive 6, wherein the value of the traction pulley diameter, further reduced, is used to determine this modified control signal. With the aid of this modified control signal, the elevator car moves again between the two floors of the building.

[0043] The next step is step S3, in which the information about the elevator car's position provided by the device 8 for determining the car's position is evaluated again to determine whether the elevator car has stopped in the predetermined stopping area of ​​the target floor.

[0044] If the elevator car has already stopped in the predetermined stopping area of ​​the target floor, the system proceeds to step S4.

[0045] In step S4, the elevator control unit receives confirmation that the elevator car has stopped in the predetermined stopping area and that no further adjustment of the traction pulley diameter value is required.

[0046] The process transitions from step S4 to step S5, where the adjustment procedure is completed.

[0047] On the other hand, if it is detected in step S6 that the elevator car has not moved beyond the predetermined stopping area, then in step S8 it is concluded that the elevator car has stopped before the predetermined stopping area, that is, it has not yet reached the predetermined stopping area.

[0048] The process transitions from step S8 to step S9. In step S9, the value specified for the traction pulley diameter is increased by a predetermined amount. This predetermined amount depends on the length of the position marker and, for example, corresponds to half the length of the position marker. The changed value of the traction pulley diameter is stored in memory, replacing the stored value of the traction pulley diameter.

[0049] Returning from step S9 to step S2, in which the elevator control unit 11 now provides a modified control signal for the traction pulley drive 6, the stored value of the traction pulley diameter being used to determine this modified control signal. With the aid of this modified control signal, the elevator car moves again between the two floors of the building.

[0050] Following this, the process proceeds to step S3, in which an evaluation of the information about the elevator car's position provided by the device 8 for determining the car's position is used to check whether the elevator car has stopped within the predetermined stopping area of ​​the target floor.

[0051] If the elevator car has already stopped in the predetermined stopping area of ​​the target floor, the system proceeds to step S4.

[0052] In step S4, it is confirmed that the elevator car has stopped in the predetermined stopping area and that no further adjustment of the traction pulley diameter is required.

[0053] Step S4 is followed by step S5, which ends the adjustment process.

[0054] Based on the above description and Figure 2As illustrated, the value of the traction pulley diameter used to determine the control signal for the traction pulley drive is iteratively adjusted until the elevator car achieves the desired stopping accuracy based on the control signal used. The adjusted traction pulley diameter value is stored in memory and retained thereafter, and is used by the elevator control unit along with other stored data and sensor signals provided during normal operation of the elevator system to control elevator operation.

Claims

1. An elevator system in which an elevator car (1) is capable of moving between two adjacent floors (40.1, 40.2) of a building (40) using a traction pulley drive in an elevator shaft (4), wherein an elevator control unit (11) for moving the elevator car from one floor to the other floor controls the traction pulley drive by means of a control signal determined using a value of the traction pulley diameter, wherein the elevator system has means (8.1, 8.2) for determining the position of the car, and the means (8.1, 8.2) has a sensor device (8.1) that detects position markers (9.1, 9.2) fastened in the elevator shaft (4) during the travel of the elevator car, characterized in that, The elevator control unit (11) is designed to: after the initial configuration of the elevator system (10), control the iterative adjustment of the value of the traction pulley diameter used to determine the control signal in order to improve the stopping accuracy of the elevator car (1), wherein the position markers (9.1, 9.2) each have a predetermined length in the direction of travel of the elevator car, and the amount by which the value of the traction pulley diameter changes during the iterative adjustment depends on the length of the position markers.

2. The elevator system according to claim 1, characterized in that, The elevator control unit (11) is designed to use the corresponding new available value of the traction pulley diameter to determine the control signal of the traction pulley drive (6) during the iterative adjustment of the traction pulley diameter.

3. The elevator system according to claim 1 or 2, characterized in that, The elevator control unit (11) is designed to terminate the iterative adjustment when the stopping accuracy of the elevator car (1) is within a predetermined stopping range.

4. The elevator system according to claim 3, characterized in that, The elevator control unit (11) is designed to reduce the diameter of the traction pulley by a certain amount when the elevator car (1) moves beyond the predetermined stopping range.

5. The elevator system according to claim 3, characterized in that, The elevator control unit (11) is designed to increase the diameter of the traction pulley by a certain amount if the predetermined stopping range is not reached.

6. The elevator system according to claim 1, characterized in that, The device for determining the position of the car has an evaluation unit (8.2) which is connected to the sensor device (8.1) and converts the sensor signals provided by the sensor device into position information.

7. The elevator system according to claim 6, characterized in that, The evaluation unit (8.2) is connected to the elevator control unit (11) and forwards the location information to the elevator control unit.

8. The elevator system according to any one of claims 6 to 7, characterized in that, The elevator system has two position markers (9.1, 9.2), one of which (9.1) is assigned to one floor and the other (9.2) is assigned to another floor.

9. The elevator system according to claim 1, characterized in that, The predetermined length is 20 cm.

10. The elevator system according to claim 1 or 9, characterized in that, After the initial configuration of the elevator system, the elevator car moves from one floor to another at a predetermined speed, and the car position is determined using information about the predetermined speed.

11. The elevator system according to claim 1 or any one of claims 9 to 10, characterized in that, The limit amount by which the diameter of the traction pulley changes during the iterative adjustment is gradually halved.

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