Patent Application
20080023272
Referring to the drawings, and initially to
A screw shaft or threaded member 20 includes an upper portion 21 vertically and rotatably attached to the supporting member 10 with such as a bearing or supporting device 22, and coupled to a first power or driving means or device 23, such as any selected motor 23 for allowing the screw shaft 20 to be rotated or driven by the first driving device 23. A driving nut or threaded member 24 is engaged or threaded with the screw shaft 20 for allowing the driving nut 24 to be moved up and down along the screw shaft 20 when the screw shaft 20 is rotated relative to the driving nut 24 by the first driving device 23. Normally, a weight (not shown) will be provided and coupled to the typical wire ropes for balancing purposes and for reducing the burden or the load applied to the screw shaft 20.
A coupling device 30 is rotatably attached or engaged onto the driving nut 24. The coupling device 30 may be rotatably secured to the driving nut 24 with one or more bearings 31, or relatively, one or more bearings 31 are disposed between the driving nut 24 and the coupling device 30, or the driving nut 24 is rotatably secured to the coupling device 30 with one or more bearings 31 for allowing the driving nut 24 to be smoothly rotated relative to the coupling device 30. The coupling device 30 is preferably attached or secured or coupled to the elevator car 12 with a soft or flexible or cushioning member (not shown) for resiliently coupling the coupling device 30 to the elevator car 12 and for preventing the coupling device 30 from being rotated or moved relative to the elevator car 12, but allowing the coupling device 30 to be moved up and down together with the elevator car 12, such that the coupling device 30 and the elevator car 12 may be moved up and down along the vertically disposed guide rails 11 by the threading engagement between the screw shaft 20 and the driving nut 24. The above-described structure is typical and will not be described in further details.
The elevator in accordance with the present invention is further to provide a second power or driving means or device 40 for moving the screw shaft 20 and/or the carriage or the elevator car 12 to a safe location when the electric driving power source has become failure. The second driving device 40 includes another power driving means or member 41, such as stepped motor, reduction gearing motor, or any other selected motor 41 disposed or attached or secured onto the coupling device 30 and includes a spindle 42 attached thereto or extended therefrom, and preferably extended out through the coupling device 30 and includes a pinion 43 attached or secured or coupled to the spindle 42 for allowing the pinion 43 to be rotated or driven by the power driving member 41 of the second driving device 40.
The second driving device 40 further includes a gear 44 attached or secured or coupled to the outer peripheral portion of the driving nut 24 and engaged or meshed with the pinion 43 for allowing the gear 44 to be rotated or driven by the driving member 41 of the second driving device 40 via the pinion 43, and thus for allowing the driving nut 24 to be selectively rotated or driven by the power driving member 41 of the second driving device 40 in order to move the coupling device 30 and the elevator car 12 along the guide rails 11, particularly to move the carriage or elevator car 12 down along the guide rails 11 to any safe location when the electric driving power source has become failure.
It is to be noted that the first driving device 23 is required to be powered or energized by a great electric power more than one (1) horse power to move or to actuate the carriage or elevator car 12 up and down relative to the supporting member 10 and along the guide rails 11, particularly to move the carriage or elevator car 12 up along the guide rails 11 to overcome the gravity force. When the electric driving power source has become failure, another great electric power electric source which is complicated and expensive is required to be provided to energize and to actuate the first driving device 23.
However, the second driving device 40 is designed to move the carriage or elevator car 12 down along the guide rails 11 that is not required to overcome the gravity force, such that the coupling device 30 and the elevator car 12 may be moved down along the guide rails 11 to any safe location when the electric driving power source has damaged or become failure or when earthquakes are occurred, and such that the second driving device 40 is not required to be powered or energized by a great electric power, and such that the second driving device 40 may be selected from battery or low powered second driving device 40 that may be operated with a less electric power more, such as lower than 200 watts, even when the electric driving power source has damaged or become failure.
In operation, the elevator car 12 may normally be moved up and down along the guide rails 11 by the first driving device 23. When the electric driving power source has damaged or become failure or when earthquakes are occurred, the second driving device 40 may be selectively powered or energized to move the coupling device 30 and the elevator car 12 down along the guide rails 11 to a lower level or to any safe location for allowing the elevator car 12 to be quickly opened and for allowing the users to get off the elevator car 12 as soon as possible.
It is further to be noted that the first driving device 23 may be the main or primary driving device for driving or rotating the screw shaft 20 relative to the driving nut 24, and the second driving device 40 may be the auxiliary driving device having a driving power smaller than that of the first driving device 23 for driving or rotating the driving nut 24 relative to the screw shaft 20. Alternatively, the second driving device 40 may also be the main or primary driving device for driving or rotating the driving nut 24 relative to the screw shaft 20, and the first driving device 23 may also be the auxiliary driving device having a driving power smaller than that of the second driving device 40 for driving or rotating the screw shaft 20 relative to the driving nut 24. The main or primary driving device operates in normal condition, but the auxiliary driving device acts when the main or primary driving device can not action.
Accordingly, the screw type elevator in accordance with the present invention includes a second driving device for moving the screw shaft and/or a carriage and for allowing the carriage to be moved to a safe location when the first driving device has become failure or has damaged, or when the electric driving power source has become failure.
Although this invention has been described with a certain degree of particularity, it is to be understood that the present disclosure has been made by way of example only and that numerous changes in the detailed construction and the combination and arrangement of parts may be resorted to without departing from the spirit and scope of the invention as hereinafter claimed.
