JP4280717B2 - Elevator with rollers having selectively variable hardness - Google Patents

Description

  The present invention generally relates to roller guide assemblies for elevator systems. More particularly, the present invention relates to a roller guide having a selectively variable roller hardness.

  Elevator systems typically include a car that travels within a hoistway to transport customers or goods between various floors of a building. Guide rails installed in the hoistway guide the elevator car in the hoistway. The elevator car includes a plurality of roller guides that guide the car along each guide rail. Non-uniformity of the guide rail can cause unwanted vibration of the elevator car. Undesirable vibrations may require rail realignment. Furthermore, the guide rails are manufactured within a specific tolerance set to give the desired elevator ride. Limited tolerances for guide rails require expensive manufacturing techniques and processes, which add to the cost of the elevator system.

  Roller guides are typically attached to the elevator car using springs or damper assemblies to mitigate and absorb some of the non-uniformity present along the guide rail and vibrations transmitted to the elevator car. Such roller guide assemblies can only accommodate a certain amount of guide rail non-uniformity and associated elevator car vibration. A constant damping rate provides optimal ride comfort within a limited operating range. In addition, the ability of the spring and damper to damp vibrations is limited by the alignment requirements required by increasing elevator car speed. The elevator car ride is balanced between a smooth ride and functional elevator parameters such as payload and elevator car speed.

  Therefore, it is desirable to develop a roller guide assembly that can adapt to vibrations and uneven guide rails to improve elevator ride comfort.

  An embodiment of the present invention includes a roller guide assembly that includes a roller having variable hardness in response to a magnetic field.

  In one example, the roller of the present invention includes a membrane that defines a generally annular chamber containing a fluid that changes viscosity characteristics in the presence of an applied magnetic field. A magnetic field generator associated with each roller generates a variable strength magnetic field to change the viscosity characteristics of the fluid. The variable viscosity characteristic of the fluid results in a corresponding change in roller hardness. The change in roller hardness provides an improved ride comfort by optimizing damping characteristics according to the currently detected elevator orientation and operating conditions (ie vibration).

  Therefore, the present invention improves the riding comfort of the elevator car by changing the roller hardness according to the current elevator operating conditions.

  Various features and advantages of this invention will become apparent to those skilled in the art from the following detailed description of the presently preferred embodiment. The drawings with detailed description are briefly described below.

  Referring to FIG. 1, a roller guide assembly 14 for an elevator system 10 includes a roller 16 having a variable hardness in response to exposure to a magnetic field 20. The roller guide assembly 14 is supported so as to move with the car 12. The roller 16 is in rotational contact with the surface of the guide rail 28.

  The hardness of each roller 16 changes according to the change of the magnetic field 20, and cancels vibration, for example. The vibration can be caused by non-uniformity of the guide rail 28 or by a combination of speed and load carried by the elevator car. In addition, lift motors and other elevator system components can contribute to unwanted vibration of the elevator car 12. The change in hardness of each roller 16 adapts to fluctuations of vibration to improve riding comfort.

  The controller 24 is programmed to selectively change the roller hardness according to the operating state. A sensor device 26 is supported for detecting vibrations and the orientation of the elevator car 12 relative to the desired orientation. The sensor device 26 is preferably an accelerometer that detects vibrations in the structure of the elevator car 12. In the illustrated example, an accelerometer is used, but any detection device known in the art may be used to obtain information about the current state, such as elevator car 12 vibration or orientation. Information from the sensor device 26 is supplied to the control device 24, which adjusts the ride comfort by controlling the roller hardness accordingly. In the illustrated embodiment, the control device 24 is supported for movement with the elevator car 12, but the control device 24 may be disposed in any other position.

  Given this description, those skilled in the art will program a commercially available controller, or develop dedicated hardware, both software, to achieve the desired roller hardness control to meet their specific needs. Will be able to.

  Each roller 16 is disposed adjacent to the magnetic field generator 18. The magnetic field generator 18 generates a magnetic field 20. Preferably, each of the plurality of rollers 16 is disposed adjacent to a separate corresponding magnetic field generator 18. A separate magnetic field generator 18 for each roller 16 provides independent control of roller hardness for each roller 16.

  Referring to FIG. 2, in one embodiment, each magnetic field generator 18 includes an electromagnet 21 configured to create an applied magnetic field 20 of varying strength, as is generally known. The electromagnet includes a coil that is energized in proportion to the desired strength of the magnetic field 20. The electromagnet 21 changes the hardness of the corresponding roller 16 by changing the magnetic field strength in proportion to the signal from the control device 24.

  Referring to FIG. 3, in another embodiment, the magnetic field generator 18 includes a permanent magnet 19. By moving the permanent magnet 19 with respect to the roller 16 (for example, as shown by the arrow 38), the intensity of the magnetic field 20 applied to the roller 16 is selectively changed. Although electromagnets and permanent magnets are shown as exemplary magnetic field generators, any device configured to produce a magnetic field that varies in proximity to the rollers 16 is within the scope of the present invention.

  Referring to FIG. 4, in one example, each roller guide assembly 14 includes three rollers 16 that guide along three surfaces of guide rails 28. Each roller 16 is supported so as to rotate about a shaft 34. The roller guide assembly 14 guides the elevator car 12 within the hoistway so as to maintain the proper orientation of the elevator car 12 and to provide a smooth and quiet ride. The load applied to each roller 16 of any one roller assembly 14 varies depending on the load on the elevator car 12 and its speed. In the present invention, the roller hardness can be optimized to change the damping characteristics of each roller 16 to accommodate and remove unwanted vibrations, thus improving ride comfort.

  Referring to FIGS. 5 and 6, each roller 16 includes a membrane 30 containing a fluid 22 having a viscosity that changes in response to changes in the strength of the applied magnetic field 20 (FIGS. 2 and 3). In one example, the fluid 22 includes a known magneto-fluidic fluid containing suspended particles that are responsive to the magnetic field 20. As is known, suspended particles in such a fluid form a columnar structure parallel to the applied magnetic field 20. The alignment of the columnar structures restricts the movement of the fluid 22 and increases the fluid viscosity. The change in the viscosity of the fluid 22 changes the damping characteristic of the roller 16.

  Any type of fluid that responds to an applied magnetic field to change its viscosity characteristics is within the scope of the present invention. Those skilled in the art who have the benefit of this description will be able to select the magnetic fluid and formulation according to the application specific parameters.

  The membrane 30 is supported around the circumference of the solid disk 31 and defines a generally annular cavity 36. The membrane 30 comprises the surface of the roller 16 that is in guiding contact with the guide rail 28. The fluid 22 in the film 30 changes its viscosity characteristics in accordance with a proportional change in the intensity of the applied magnetic field 20. A change in the viscosity of the fluid 22 causes a corresponding change in the hardness of the roller 16 to compensate and damp the vibration of the elevator car 12.

  Referring to FIG. 1, during operation of the elevator system 10, the sensor 26 communicates information indicating the vibration and orientation of the elevator car 12 to the controller 24. The control device 24 compares the information about the vibration and direction from the sensor 26 with a desired state. The detection device 26 detects the current state of the elevator car 12 resulting from loads, guide rail unevenness, vibration, speed, and many other operating parameters and mechanisms required for operation of the elevator system 10.

  The controller 24 compares the detected state with the desired state, and controls each magnetic field generator 18 accordingly to produce a corresponding magnetic field 20 to control the viscosity characteristics of the fluid 22 and the desired for each roller 16. Get hardness. The strength of the magnetic field 20 is changed for each dedicated roller 16 in proportion to the difference between the desired state and the detected state. The damping characteristics for each roller 16 are optimized so as to attenuate and isolate the vibration of the elevator car 12 by changing the hardness. Further, the controller 24 independently controls the hardness of each roller 16 so that the combined effect of the damping characteristics is optimal and provides a smoother ride.

  The operation of the elevator system 10 of the present invention improves ride comfort and reliability by reducing the effects of vibration during the movement of the elevator car 12. Furthermore, the optimization of the selectively variable damping characteristics of the roller 16 of the present invention accommodates a wider variety of guide rails 28.

  The above description is merely an example, and is not merely a specific specification. While this invention has been described in an illustrative manner, it is to be understood that the terminology used is not a limiting term and is intended to have the character of descriptive terms. Many modifications and variations of the present invention are possible in light of the above teachings. While preferred embodiments of the present invention have been described, those skilled in the art will recognize that certain variations are within the scope of the present invention. It goes without saying that the invention may be practiced otherwise than as specifically described within the scope of the appended claims. For that reason, the following claims should be studied to determine the true scope and content of this invention.

1 is a schematic diagram of an elevator car including an example roller guide assembly designed in accordance with the present invention. The schematic diagram of the Example of a magnetic field generator. The schematic diagram of another Example of a magnetic field generator. The schematic diagram of the roller guide assembly which contacts a guide rail. FIG. 2 is a view of a roller guide designed in accordance with the present invention. FIG. 2 is a view of a roller guide designed in accordance with the present invention.

Claims (19)

A roller (16) having a hardness that varies according to the magnetic field (20) ;
A magnetic field generator (18) for selectively generating the magnetic field (20);
A roller guide assembly (14) for an elevator system (10).   2. An assembly according to claim 1, characterized in that the roller (16) comprises a membrane (30) containing a fluid (22) having a viscosity which varies according to the magnetic field (20).   The assembly of claim 2, wherein said fluid (22) comprises a magnetic fluid.   3. An assembly according to claim 2, characterized in that the membrane (30) defines a generally annular chamber (36) supported around a disc (31).   The assembly of claim 1, including a magnetic field generator (18) adjacent to the roller (16) that is selectively controllable to change the hardness of the roller (16).   6. An assembly according to claim 5, comprising a plurality of said rollers (16) and a corresponding plurality of separately actuable magnetic field generators (18).   6. Assembly according to claim 5, characterized in that the magnetic field generator (18) comprises an electromagnet (21).   6. Assembly according to claim 5, characterized in that the magnetic field generator (18) comprises a permanent magnet (19). At least one guide rail (28);
An elevator car (12) movable along the guide rail (28);
A roller (16) supported to move with the elevator car (12), having a hardness that rolls along the surface of the guide rail (28) and varies with the magnetic field (20);
A magnetic field generator (18) for selectively generating the magnetic field (20);
An elevator system (10) comprising:   The system of claim 9, wherein the roller (16) includes a membrane (30) containing a fluid (22) having a viscosity that varies in response to the magnetic field (20).   The system of claim 10, wherein the membrane (30) defines a generally annular chamber (36) supported about a disk (31).   The system of claim 10, wherein the membrane (30) is in rolling contact with the surface of the guide rail (28).   10. The system according to claim 9, comprising a plurality of rollers (16) and a corresponding plurality of magnetic field generators (18).   14. System according to claim 13, comprising a control device (24) for selectively and individually controlling the magnetic field generator (18).   A sensor device (26) for providing information on the orientation of the elevator car (12) and the magnetic field (20) generator for receiving information from the sensor device (26) and changing the roller hardness accordingly. 10. System according to claim 9, characterized in that it comprises a control device (24) for controlling. A method of controlling vibration of an elevator car (12) having a plurality of associated rollers (16) adapted to guide the elevator car (12) along a guide rail (28) comprising:
a) determining the state of the elevator car (12) for a desired state;
b) Depending on the state of the determined, and selectively changing the hardness of the one roller even without least by a variable magnetic field (20) generated by the magnetic field generator (18),
A method comprising the steps of: Comprising providing said roller including a fluid having a viscosity that varies depending on the magnetic field,
The method of claim 16, wherein step (b) comprises selectively changing the magnetic field associated with a particular roller (16).   18. Method according to claim 17, comprising changing the strength of the magnetic field (20) independently for each roller (16).   The method of claim 16, wherein step (a) comprises determining a vibration level of the car as the car moves along the guide rail.

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