Elevator systems are useful for carrying passengers and items between different levels of a building. Many elevator systems are traction-based and include traction ropes that suspend the elevator car and a counterweight. A machine causes movement of a traction sheave that, in turn, causes movement of the traction ropes for moving the elevator car as desired. Other elevator systems are hydraulic and include an expanding cylinder that raises or lowers the elevator car.
Each type of elevator system has limitations. For example, the ropes of traction-based systems introduce significant weight and expense in high-rise building installations. The traction ropes may also experience sway under various conditions. One limitation on hydraulic elevator systems is that they are not practical for high rise buildings.
Elevator system providers are always striving to increase the efficiencies and economies of elevator systems. For example, various proposals have been made to include more than one elevator car in a single hoistway to increase the passenger-carrying capacity while occupying less building space. Such proposals are often considered too complicated and have not been widely adopted.
An illustrative example embodiment of an elevator system includes a platform and a plurality of supports configured to selectively engage a nearby structure. The plurality of supports include at least a first support and a second support. The first and second supports alternate between engaging the nearby structure to support the platform while the other one of the supports is disengaged from the nearby structure. At least one of the first and second supports is configured to move relative to the platform while engaging the nearby structure to cause vertical movement of the platform.
In an example embodiment having at least one feature of the elevator system of the previous paragraph, at least one of the first and second supports extends or contracts while engaging the nearby structure to cause the vertical movement of the platform.
In an example embodiment having at least one feature of the elevator system of any of the previous paragraphs, each of the supports has a vertical stroke corresponding to a distance between a fully contracted position and a fully extended position of the support, and both of the first and second supports simultaneously engage the nearby structure while extending or contracting along at least a portion of the vertical stroke of the support such that both of the first and second supports simultaneously cause the vertical movement of the platform.
In an example embodiment having at least one feature of the elevator system of any of the previous paragraphs, the first support extends over the portion of the vertical stroke, and the second support contracts over the portion of the vertical stroke.
In an example embodiment having at least one feature of the elevator system of any of the previous paragraphs, one of the first and second supports engages the nearby structure while extending or contracting along another portion of the vertical stroke of the support simultaneously with the other of the second and first supports contracting or extending along another portion of the vertical stroke of the support while being disengaged from the nearby structure.
In an example embodiment having at least one feature of the elevator system of any of the previous paragraphs, at least some of the supports each comprise an articulating robotic arm.
In an example embodiment having at least one feature of the elevator system of any of the previous paragraphs, at least some of the supports each comprise a pressurized cylinder.
In an example embodiment having at least one feature of the elevator system of any of the previous paragraphs, the supports each comprise a grip near one end of the support configured to engage the nearby structure.
In an example embodiment having at least one feature of the elevator system of any of the previous paragraphs, the grips are respectively configured to engage at least one type of feature selected from the group of features consisting of a wall, a pole, a rail, a rope, a belt, a rung, a groove, a flange, a tooth and a rib.
In an example embodiment having at least one feature of the elevator system of any of the previous paragraphs, the first support is situated relative to the platform for extending above the platform, and the second support is situated relative to the platform for extending beneath the platform.
In an example embodiment having at least one feature of the elevator system of any of the previous paragraphs, the first and second supports each engage the nearby structure adjacent a first side of the platform, and the platform includes at least one follower on a second side of the platform that is configured to follow along a nearby structure adjacent the second side of the platform.
In an example embodiment having at least one feature of the elevator system of any of the previous paragraphs, the at least one follower comprises a plurality of rollers.
In an example embodiment having at least one feature of the elevator system of any of the previous paragraphs, the plurality of supports includes at least two of the supports situated relative to the platform for extending above the platform and at least two others of the supports situated relative to the platform for extending beneath the platform.
In an example embodiment having at least one feature of the elevator system of any of the previous paragraphs, the platform is part of an elevator car including a cabin configured to accommodate a plurality of passengers.
An illustrative example embodiment of a method of controlling movement of an elevator platform includes: selectively engaging a nearby structure using supports associated with the platform, alternating between engaging the nearby structure using at least a first one of the supports or at least a second one of the supports to support the platform while the other one of the supports is disengaged from the nearby structure, and moving at least one of the first and second supports relative to the platform while engaging the nearby structure to cause vertical movement of the platform.
In an example embodiment having at least one feature of the method of the previous paragraph, the moving comprises extending or contracting the at least one of the first and second supports while engaging the nearby structure to cause the vertical movement of the platform.
In an example embodiment having at least one feature of the method of any of the previous paragraphs, each of the supports has a vertical stroke corresponding to a distance between a fully contracted position and a fully extended position of the support, and the method comprises simultaneously engaging the nearby structure while extending or contracting both of the first and second supports along at least a portion of the vertical stroke of the support such that both of the first and second one of the supports simultaneously cause the vertical movement of the platform.
An example embodiment having at least one feature of the method of any of the previous paragraphs includes extending the first one of the supports over the portion of the vertical stroke simultaneously with contracting the second one of the supports over the portion of the vertical stroke.
An example embodiment having at least one feature of the method of any of the previous paragraphs includes engaging the nearby structure by one of the first and second supports while extending or contracting along another portion of the vertical stroke of the support simultaneously with disengaging the other of the second and first supports from the nearby structure while contracting or extending the support along another portion of the vertical stroke of the support.
An example embodiment having at least one feature of the method of any of the previous paragraphs includes extending the first one of the supports above the platform, and extending the second one of the supports beneath the platform.
The various features and advantages of at least one disclosed example embodiment 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.
A plurality of supports 30 are configured to move relative to the platform in a manner that causes vertical movement of the platform 22. In the example of
The plurality of supports 30 are configured to sequentially and alternately engage a nearby structure 40 and to extend or contract to cause vertical movement of the platform 22. The first support 32 and the second support 34 sequentially alternate between engaging the nearby structure 40 to support the platform 22 while the other support is disengaged from the nearby structure 40. At least the one of the supports 30 that engages the nearby structure 40 moves relative to the platform 22 to cause vertical movement of the platform 22. In this example embodiment, the movement of the supports 30 relative to the platform 22 includes extending and contracting. The first support 32 is schematically shown in an extended position or condition while the second support 34 is schematically illustrated in a contracted position or condition.
The supports 30 in the illustrated example embodiment each comprise an articulated robotic arm. Coordinated extending and contracting movement of the robotic arm supports 30 achieves desired vertical movement of the elevator car 24 as the first supports 32A and 32B and the second supports 34A and 34B sequentially alternate between engaging the hoistway walls 40 to support the platform 22 while the other supports are disengaged from the hoistway walls 40. For example, the first supports 32A and 32B may first be extended above the elevator car 24 and engage the hoistway walls 40. The second supports 34A and 34B may then disengage from the hoistway walls 40 and contract upward toward the platform 22. At the same time, the first supports 32A and 32B contract, pulling the elevator car 24 vertically upward. At some point the second supports 34A and 34B engage the hoistway walls 40 and then extend, further propelling the elevator car 24 vertically upward. While the second supports 34A and 34B are engaged with the hoistway walls 40, the first supports 34A and 34B can disengage and extend again above the elevator car 24. Such sequential and alternating engagement and disengagement from the nearby structure 40 while extending or contracting, allows the supports 30 to secure the platform 22 against undesired movement and achieve the desired vertical movement.
Different coordinated movements are possible among the plurality of supports 30 associated with each platform 22 to achieve desired support of the platform 22 and a desired speed of vertical movement. For example, each of the supports 30 has a vertical stroke corresponding to a distance between a fully contracted position and a fully extended position of the support 30. The first supports 32A and 32B can simultaneously engage the nearby structure 40 while the second supports 34A and 34B also engage the nearby structure 40. All of the first supports 32A, 32B and the second supports 34A, 34B can simultaneously extend or contract along at least a portion of the vertical stroke of the support such that the first supports 32A, 32B and the second supports 34A, 34B simultaneously cause vertical movement of the platform 22. During such motion causing downward movement of the platform 22, the first supports 32A, 32B extend over the portion of the vertical stroke while the second supports 34A, 34B contract over a corresponding portion of their vertical stroke.
In some such embodiments, at least the first supports 32A, 32B or the second supports 34A, 34B engages the nearby structure 40 while extending or contracting along another portion of the vertical stroke of those supports. At the same time, the other of the second supports 34A, 34B or the first supports 32A, 32B contracts or extends along another portion of the vertical stroke of those supports while being disengaged from the nearby structure 40.
A variety of timings are possible between the engagement and disengagement of the supports 30 from the nearby structure 40 and a variety of percentages of the vertical stroke of each support may be used while engaged with the nearby structure 40 to achieve desired movement of the platform 22.
Such coordinated movement can facilitate relatively quick vertical movement of the platform 22 while always having at least some of the supports 30 engaged with the nearby structure 40 to support the platform 22 in a way that controls any vertical movement of the platform.
One feature of the example arrangement shown in
The various elevator system configurations described above and illustrated in the figures have features that are not necessarily limited to just that particular embodiment or configuration. Various other combinations of the individual features of those embodiments are possible to realize still other embodiments. For example, it is possible to utilize vertically extending members 40 like those shown in
The platforms 22 in the illustrations are associated with a cabin. Other platform configurations can be used with supports 30 for various purposes in an elevator system. For example, a platform may be configured for installation of elevator system components and used for positioning equipment or workers in a hoistway during installation or maintenance. Other platform configurations are useful for rescue operations to carry an individual along a hoistway into a position to attend to passengers in a car that is stopped in the hoistway. In some such systems, the platform and supports operate independently of the passenger-carrying car of the elevator system.
The preceding 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 this invention. The scope of legal protection given to this invention can only be determined by studying the following claims.