Dust mitigation for optical position reference system of elevator system

Abstract

The invention relates to dust mitigation for an optical position reference system of an elevator system. Specifically, a position reference system of an elevator system includes a reference element having a fixed position in a hoistway of the elevator system, and an optical sensor configured to move along the hoistway with an elevator car of the elevator system and configured to transmit a signal to the reference element to determine a position of the elevator car. The airflow conduit is configured to move along the hoistway with the elevator car. The airflow conduit is configured to passively direct airflow toward the reference element to prevent particles from accumulating on the reference element.

Description

Technical Field

[0001] Exemplary embodiments relate to the art of elevator systems, and in particular to a position reference system (PRS) for an elevator system. Background Art

[0002] Elevator systems typically include a position reference system (PRS) that is used to determine the position of the elevator car in the hoistway. In some elevator systems, the PRS is an optical system in which an information tape is mounted vertically in the hoistway and is read by an optical sensor mounted on the elevator car to determine the position of the elevator car in the hoistway. However, the hoistway environment can be dusty, which interferes with the function of the optical sensor. Summary of the invention

[0003] In one exemplary embodiment, a position reference system for an elevator system includes a reference element having a fixed position in a hoistway of the elevator system, and an optical sensor configured to move along the hoistway with an elevator car of the elevator system and configured to transmit a signal to the reference element to determine the position of the elevator car. An airflow duct is configured to move along the hoistway with the elevator car. The airflow duct is configured to passively direct airflow toward the reference element to prevent particles from accumulating on the reference element.

[0004] Additionally or alternatively, in this or other embodiments, the airflow duct includes a duct body, one or more duct inlets located at one or more of the first duct end and the second duct end, and one or more duct outlets located along the duct body between the first duct end and the second duct end. The one or more duct outlets are configured to direct the airflow out of the airflow duct and toward the reference element.

[0005] Additionally or alternatively, in this or other embodiments, the one or more duct inlets face vertically downward when in a mounted position on the elevator car.

[0006] Additionally or alternatively, in this or other embodiments, one or more duct inlets face upward when in a mounted position on the elevator car.

[0007] Additionally or alternatively, in this or other embodiments, the reference element is a coding strip.

[0008] Additionally or alternatively, in this or other embodiments, the airflow duct is positioned vertically above the optical sensor.

[0009] Additionally or alternatively, in this or other embodiments, the airflow duct is positioned vertically below the optical sensor.

[0010] In another exemplary embodiment, an elevator system includes a hoistway, an elevator car positioned in the hoistway and movable along the length of the hoistway, and a position reference system located in the hoistway and configured to determine the position of the elevator car in the hoistway. The position reference system includes a reference element having a fixed position in the hoistway, and an optical sensor configured to move along the hoistway with the elevator car and configured to transmit a signal to the reference element to determine the position of the elevator car. An airflow duct is configured to move along the hoistway with the elevator car. The airflow duct is configured to passively direct the airflow toward the reference element to prevent particles from accumulating on the reference element.

[0011] Additionally or alternatively, in this or other embodiments, the airflow duct includes a duct body, one or more duct inlets located at one or more of the first duct end and the second duct end, and one or more duct outlets located along the duct body between the first duct end and the second duct end. The one or more duct outlets are configured to direct the airflow out of the airflow duct and toward the reference element.

[0012] Additionally or alternatively, in this or other embodiments, the one or more duct inlets face vertically downward when in a mounted position on the elevator car.

[0013] Additionally or alternatively, in this or other embodiments, one or more duct outlets face vertically upward when in a mounted position on the elevator car.

[0014] Additionally or alternatively, in this or other embodiments, the reference element is a coding strip.

[0015] Additionally or alternatively, in this or other embodiments, the airflow duct is positioned vertically above the optical sensor.

[0016] Additionally or alternatively, in this or other embodiments, the airflow duct is positioned vertically below the optical sensor.

[0017] In yet another exemplary embodiment, a method of operating an elevator system includes moving an elevator car along a hoistway, and determining a position of the elevator car in the hoistway via a position reference system. The position reference system includes a reference element fixed in the hoistway, and an optical sensor configured to move along the hoistway with the elevator car and configured to transmit a signal to the reference element to determine the position of the elevator car. Airflow is passively pushed toward the reference element via movement of the elevator car along the hoistway to prevent particles from accumulating on the reference element.

[0018] Additionally or alternatively, in this or other embodiments, the airflow is urged toward the reference element via an airflow duct located at the elevator car and movable along the hoistway with the elevator car. The airflow duct includes a duct body, one or more duct inlets located at one or more of a first duct end and a second duct end, and one or more duct outlets located along the duct body between the first duct end and the second duct end, the one or more duct outlets being configured to direct the airflow out of the airflow duct and toward the reference element.

[0019] Additionally or alternatively, in this or other embodiments, the elevator car is moved downward in the hoistway to urge the airflow toward the reference element.

[0020] Additionally or alternatively, in this or other embodiments, the one or more duct inlets face vertically downward when in a mounted position on the elevator car.

[0021] Additionally or alternatively, in this or other embodiments, the reference element is a coding strip.

[0022] Additionally or alternatively, in this or other embodiments, the airflow duct is positioned vertically above the optical sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The following description should not be considered limiting in any way. Referring to the accompanying drawings, like elements are numbered alike:

[0024] Figure 1 is a schematic diagram of an embodiment of an elevator system;

[0025] Figure 2 is a schematic diagram of an embodiment of a position reference system for an elevator system;

[0026] Figure 3 is a diagram of an embodiment of an airflow duct of a position referencing system; and

[0027] Figure 4 is a diagrammatic representation of another embodiment of an airflow duct of a position referencing system. DETAILED DESCRIPTION

[0028] A detailed description of one or more embodiments of the disclosed apparatus and methods is given herein by way of example and not limitation with reference to the figures.

[0029] Figure 11 is a perspective view of an elevator system 101, which includes an elevator car 103, a counterweight 105, a tension member 107, a guide rail 109, a machine 111, a position reference system 113, and a controller 115. The elevator car 103 and the counterweight 105 are connected to each other by the tension member 107. The tension member 107 may include or be configured as, for example, a rope, a cable, and / or a coated steel belt. The counterweight 105 is configured to balance the load of the elevator car 103 and is configured to facilitate movement of the elevator car 103 within an elevator shaft or hoistway 117 and along the guide rail 109 simultaneously and in opposite directions relative to the counterweight 105.

[0030] The tension member 107 engages a machine 111, which is part of the top structure of the elevator system 101. The machine 111 is configured to control the movement between the elevator car 103 and the counterweight 105. As shown, the controller 115 can be located in a controller room 121 of the hoistway 117 and is configured to control the operation of the elevator system 101 and, in particular, the elevator car 103. It is to be appreciated that the controller 115 need not be in the controller room 121, but can be in the hoistway or other locations in the elevator system. For example, the controller 115 can provide drive signals to the machine 111 to control the acceleration, deceleration, leveling, stopping, etc. of the elevator car 103. The controller 115 can also be configured to receive position signals from the position reference system 113 or any other desired position reference device. When moving up or down along the guide rail 109 in the hoistway 117, the elevator car 103 can stop at one or more landings 125 as controlled by the controller 115. Although shown in the controller room 121, those skilled in the art will recognize that the controller 115 may be located and / or configured at other locations or positions within the elevator system 101. In one embodiment, the controller 115 may be located remotely or in a distributed computing network (e.g., a cloud computing architecture). The controller 115 may be implemented using a processor-based machine (such as a personal computer, a server, a distributed computing network, etc.).

[0031] The machine 111 may include a motor or similar drive mechanism. According to an embodiment of the present disclosure, the machine 111 is configured to include an electrically driven motor. The power supply for the motor may be any power source including a power grid that is combined with other components to supply the motor. The machine 111 may include a traction sheave that applies force to the tension member 107 to move the elevator car 103 within the hoistway 117.

[0032] The elevator system 101 also includes one or more elevator doors 104. The elevator doors 104 may be attached to the elevator car 103, or the elevator doors 104 may be located on a landing 125 of the elevator system 101, or both. The embodiments disclosed herein may be applicable to elevator doors 104 attached to the elevator car 103, or elevator doors 104 located on a landing 125 of the elevator system 101, or both. The elevator doors 104 open to allow passengers to enter and exit the elevator car 103.

[0033] Reference now Figure 2 , the position reference system 113 includes a reference element, such as an encoded tape 200 extending along the vertical length of the hoistway 117 and fixed in the hoistway 117. The tape 200 is encoded with information, which is embossed on the tape 200 or embedded in the tape 200, which, when read by the optical sensor 202, indicates the vertical position of the elevator car 103 in the hoistway 117. The optical sensor 202 is disposed at the elevator car 103 and travels along the hoistway 117 with the elevator car 103. The optical sensor 202 is located, for example, at the top plate 208 of the elevator car 103. In some embodiments, the tape 200 is formed of, for example, a metal or plastic material. The tape 200 is fixed in the hoistway 117 via a plurality of guide clips 204 along the hoistway 117 and a tension lock 206 configured to maintain a selected tension on the tape 200. The tension lock 206 is located at the vertical upper end of the tape 200 and at the vertical lower end (not shown) of the tape 200.

[0034] The optical sensor 202 may be, for example, a dual camera sensor including a light source (not shown). To determine the position, the belt 200 is illuminated by, for example, a light source that emits one or more short infrared pulses. When the belt 200 is illuminated, the optical sensor 202 records a pattern on the belt 200 in front of the optical sensor 202. The optical sensor 202 transmits a signal indicating the pattern read by the optical sensor 202 to the controller 115, and the controller 115 determines the position of the elevator car 103.

[0035] Dust and other particles in the hoistway may accumulate on the belt 200, which may interfere with the operation of the optical sensor 202. To alleviate this problem, an airflow duct 210 is mounted on the elevator car 103. The airflow duct 210 includes one or more duct inlets 212 and one or more duct outlets 214 to direct an airflow 216 toward the belt 200 to remove any accumulated dust or other particles from the belt 200.

[0036] Reference now Figure 3, the airflow duct 210 is, for example, U-shaped and has two duct inlets 212, wherein the duct inlet 212 is located at each of a first duct end 218 and a second duct end 220 opposite the first duct end 218. The airflow duct 210 can be formed of a material such as plastic, metal, or a composite material. One or more duct outlets 214 are located along the duct body 222 between the first duct end 218 and the second duct end 220 and are configured and oriented to direct the airflow 216 toward the belt 200. In some embodiments, the airflow duct 210 has a constant circular cross-section, and Figure 4 In other embodiments shown in FIG. 1 , the cross-sectional shape and / or size of the cross-sectional area of ​​the airflow duct 210 can be varied between one or more duct inlets 212 and one or more duct outlets 214 to provide desired characteristics of the airflow 216, such as airflow pressure or flow rate. Figure 4 As shown in , the cross-section of the airflow duct 210 may be a converging configuration such that the cross-sectional area of ​​the airflow duct 210 is larger at one or more duct inlets 212 than at or near one or more duct outlets 214 .

[0037] Reference again Figure 3 In some embodiments, one or more duct outlets 214 are located at a midpoint portion of duct body 222. In some embodiments, one or more duct outlets 214 are three duct outlets 214 arranged in a linear arrangement substantially horizontally across belt 200. Duct outlets 214 may be configured to direct airflow 216 out of duct outlets 214 in substantially parallel streams. In some embodiments, duct outlets 214 are circular, while in other embodiments, duct outlets 214 may have other shapes, such as elliptical, quadrilateral (e.g., Figure 4 However, those skilled in the art will readily recognize that the configurations described herein are merely exemplary, and in other configurations, the duct outlet 214 may have other arrangements, such as, for example, nozzle structures such as holes, slits, or protrusions, to provide selected characteristics of the airflow 216.

[0038] Reference again Figure 2 , the airflow duct 210 is located at the elevator car 103 and travels along the hoistway 117 with the elevator car 103. In some embodiments, the airflow duct 210 is positioned on the elevator car 103 so that the duct inlet 212 is located vertically below the duct outlet 214, and can be further positioned so that the duct outlet 214 is located vertically above the optical sensor 202. In operation, when the elevator car 103 travels downward in the hoistway 117, the downward travel of the elevator car 103 pushes the airflow 216 into the airflow duct 210 via the duct inlet 212. When the airflow duct 210 is in the installed position, the duct inlet 212 faces vertically downward, as shown in FIG. Figure 2The airflow 216 is then directed along the duct body 222 and outwardly through the duct outlet 214 toward the belt 200. The airflow 216 directed toward the belt 200 removes dust and other particles from the belt 200, which improves the operation of the position reference system 113.

[0039] The airflow duct 210 passively provides cleaning of the belt 200, requiring no additional power beyond that required to move the elevator car 103 along the hoistway 117. In addition, the downward orientation of the duct inlet 212 prevents dust from accumulating in the airflow duct 210 when the elevator car 103 is stationary. Alternatively, the air duct inlet 212 may be located in an upward direction to promote airflow when the car 103 travels upward in the hoistway 117. To prevent dust from accumulating in the airflow duct 210, a porous filter (not shown) may be installed at the opening 212 to prevent dust from accumulating in the airflow duct 210.

[0040] The term "about" is intended to include the degree of error associated with the measurement of a particular quantity based on the equipment available at the time the application was filed.

[0041] The terms used herein are only used for the purpose of describing specific embodiments and are not intended to limit the present disclosure. As used herein, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and / or "comprising" when used in this specification indicate the presence of the indicated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or combinations thereof.

[0042] Although the present disclosure has been described with reference to one or more exemplary embodiments, it will be appreciated by those skilled in the art that various changes may be made and equivalents may be substituted for its elements without departing from the scope of the present disclosure. In addition, many modifications may be made to adapt specific situations or materials to the teachings of the present disclosure without departing from its basic scope. Therefore, it is intended that the present disclosure is not limited to the specific embodiments disclosed as the best mode for carrying out the present disclosure, but that the present disclosure will include all embodiments that fall within the scope of the claims.

Claims

1. A position reference system for an elevator system, comprising: a reference element having a fixed position in a hoistway of the elevator system; an optical sensor configured to move along the hoistway with an elevator car of the elevator system and configured to transmit a signal to the reference element to determine a position of the elevator car; as well as An airflow duct is configured to move along the hoistway with the elevator car, the airflow duct being configured to passively direct airflow toward the reference element to prevent particle accumulation on the reference element.

2. The position reference system according to claim 1, wherein: The air flow duct comprises: Pipeline body; one or more conduit inlets at one or more of the first conduit end and the second conduit end; and One or more duct outlets are located along the duct body between the first duct end and the second duct end, the one or more duct outlets being configured to direct the airflow out of the airflow duct and toward the reference element.

3. The position reference system according to claim 2, wherein: When in the mounted position on the elevator car, the one or more duct inlets face vertically downward.

4. The position reference system according to claim 2, wherein: When in the mounted position on the elevator car, the one or more duct inlets face upwards.

5. The position reference system according to claim 1, wherein: The reference element is a coding strip.

6. The position reference system according to claim 1, wherein: The airflow duct is positioned vertically above the optical sensor.

7. The position reference system according to claim 1, wherein: The airflow duct is positioned vertically below the optical sensor.

8. An elevator system, comprising: Well; an elevator car disposed in the hoistway and movable along the length of the hoistway; as well as A position reference system disposed in the hoistway and configured to determine a position of the elevator car in the hoistway, the position reference system comprising: a reference element having a fixed position in the hoistway; an optical sensor configured to move along the hoistway with the elevator car and configured to transmit a signal to the reference element to determine a position of the elevator car; and An airflow duct is configured to move along the hoistway with the elevator car, the airflow duct being configured to passively direct airflow toward the reference element to prevent particle accumulation on the reference element.

9. The elevator system according to claim 8, wherein: The air flow duct comprises: Pipeline body; one or more conduit inlets at one or more of the first conduit end and the second conduit end; and One or more duct outlets are located along the duct body between the first duct end and the second duct end, the one or more duct outlets being configured to direct the airflow out of the airflow duct and toward the reference element.

10. The elevator system according to claim 9, wherein: When in the mounted position on the elevator car, the one or more duct inlets face vertically downward.

11. The elevator system according to claim 9, wherein: When in the mounted position on the elevator car, the one or more duct outlets face vertically upwards.

12. The elevator system according to claim 8, wherein: The reference element is a coding strip.

13. The elevator system according to claim 8, wherein: The airflow duct is positioned vertically above the optical sensor.

14. The elevator system according to claim 8, wherein: The airflow duct is positioned vertically below the optical sensor.

15. A method of operating an elevator system, comprising: Moving the elevator car along the hoistway; The position of the elevator car in the hoistway is determined via a position reference system, the position reference system comprising: a reference element fixed in the hoistway; and an optical sensor configured to move along the hoistway with the elevator car and configured to transmit a signal to the reference element to determine a position of the elevator car; Airflow is passively urged toward the reference element via movement of the elevator car along the hoistway to prevent particle accumulation on the reference element.

16. The method of claim 15, further comprising pushing the airflow toward the reference element via an airflow duct located at the elevator car and movable along the hoistway with the elevator car, the airflow duct comprising: Pipeline body; one or more conduit inlets at one or more of the first conduit end and the second conduit end; as well as One or more duct outlets are located along the duct body between the first duct end and the second duct end, the one or more duct outlets being configured to direct the airflow out of the airflow duct and toward the reference element.

17. The method of claim 15, further comprising moving the elevator car downward in the hoistway to urge the airflow toward the reference element.

18. The method according to claim 17, wherein: When in the mounted position on the elevator car, the one or more duct inlets face vertically downward.

19. The method according to claim 15, wherein: The reference element is a coding strip.

20. The method according to claim 15, wherein: The airflow duct is positioned vertically above the optical sensor.

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