Patent Publication Number: US-11040853-B2

Title: Elevator system hoistway access control

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application is a National Stage application of PCT/IB2015/000848, filed May 7, 2015, the entire contents of which are hereby incorporated by reference. 
     BACKGROUND 
     The subject matter disclosed herein relates to elevator systems. More particularly, the present disclosure relates to hoistway access control for technicians and/or maintenance personnel. 
     In current, typical elevator systems, when elevator car doors are opened at a landing floor, there is a clearance or gap between the landing door and the car door of, in some systems, about 30 mm. Because of this clearance, dust or passenger goods (e.g.: keys or other items) can fall in the hoistway and land in the pit at the bottom of the hoistway. Consequently, the pit has to be frequently cleaned. To clean the pit or to retrieve passenger goods that fall into the pit, mechanics or the house keepers have to open the lowest landing door and access the pit with a pit ladder, climbing down the pit ladder to clean the pit and/or retrieve the items. 
     In order to protect the mechanics or technicians, etc., during those operations, codes and/or regulations have specified a safety volume and clearance for technicians entering the hoistway resulting in a larger overall volume of the elevator systems, while elevator system customers desire that the elevator system occupy a smaller overall volume. Thus, new elevator systems are being developed in which many maintenance activities can be performed from inside the car, alleviating the need to provide such a safety volume in the pit. A way for accessing the pit to clean the pit and/or retrieve customer items still must be provided, however as the clearance of 30 mm will be still needed. 
     BRIEF SUMMARY 
     In one embodiment, a hoistway access system for an elevator system includes an access switch positioned at a selected landing floor of a hoistway of an elevator system and operably connected to a controller. A remote controlled lock is located at landing doors of a landing floor providing access to a hoistway pit, the lock operably connected to the controller. A safety actuation system is operably connected to an elevator car located in the hoistway and operably connected to the controller. The controller is configured to command a drive system to drive the elevator car to an upper location of the hoistway when the access switch is activated, the upper location sufficient to define a selected safety volume in the hoistway defined by the hoistway pit and the elevator car. The controller is configured to command engagement of the safety actuation system to stop and hold the elevator car in the hoistway via a car guide rail, and command the remote controlled lock to unlock when the safety actuation system is engaged, thereby allowing access to the hoistway via the landing doors providing access to the hoistway pit. 
     Additionally or alternatively, in this or other embodiments the access switch is activated by one of a key, a key pad or a magnetic card. 
     Additionally or alternatively, in this or other embodiments the upper location of the hoistway is an uppermost landing floor of the elevator system. 
     Additionally or alternatively, in this or other embodiments the safety actuation system is one of mechanically or electrically operated. 
     In another embodiment, a method for accessing a hoistway of an elevator system includes activating an access switch located at a landing floor of the elevator system and driving an elevator car located in the hoistway to a selected upper location of the hoistway via activation of the access switch to define a selected safety volume in the hoistway defined by a hoistway pit and the elevator car. A safety actuation system located at the elevator car is engaged to stop and hold the elevator car at the selected upper location in the hoistway. A landing door providing access to the pit is opened at the landing floor when the elevator car safeties are engaged via the safety actuation system, thereby allowing access to the hoistway via the landing doors. 
     Additionally or alternatively, in this or other embodiments a remote controlled lock is disengaged at the landing floor doors automatically when the elevator car safeties are engaged, thereby allowing opening of the landing floor doors. 
     Additionally or alternatively, in this or other embodiments the hoistway is entered to clean the hoistway pit and/or retrieve items from the hoistway pit. 
     Additionally or alternatively, in this or other embodiments the landing floor doors are closed after accessing the hoistway and deactivating the access switch. 
     Additionally or alternatively, in this or other embodiments deactivating the access switch returns the elevator system to a normal operational mode. 
     Additionally or alternatively, in this or other embodiments the landing floor is a landing floor providing access to the hoistway pit of the elevator system. 
     Additionally or alternatively, in this or other embodiments the selected upper location is an uppermost landing floor of the elevator system. 
     Additionally or alternatively, in this or other embodiments the safety actuation system is one of electrically or mechanically operated. 
     In yet another embodiment, an elevator system includes a hoistway, an elevator car located in and drivable along the hoistway, and a hoistway access system. The hoistway access system includes an access switch positioned at a selected landing floor of the hoistway and operably connected to a controller, a remote controlled lock located at landing doors of the selected landing floor and operably connected to the controller, and a safety system located at the elevator car and operably connected to the controller. The controller is configured to command a drive system to drive the elevator car to a selected upper location of the hoistway when the access switch is activated, command engagement of the safety system to stop and hold the elevator car a guide rail at the selected upper location, and command the remote controlled lock to unlock when the safety system is engaged, thereby allowing access to the hoistway via the landing doors. 
     Additionally or alternatively, in this or other embodiments the access switch is activated by a one of a key, key pad or magnetic card. 
     Additionally or alternatively, in this or other embodiments the selected upper location of the hoistway is an uppermost landing floor of the elevator system. 
     Additionally or alternatively, in this or other embodiments the selected landing floor provides access to a hoistway pit of the elevator system. 
     Additionally or alternatively, in this or other embodiments the safety system is one of electrically or mechanically operated. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The subject matter is particularly pointed out and distinctly claimed at the conclusion of the specification. The foregoing and other features, and advantages of the present disclosure are apparent from the following detailed description taken in conjunction with the accompanying drawings in which: 
         FIG. 1  is a schematic view of an embodiment of an elevator system; 
         FIG. 2  is a schematic of an embodiment of a hoistway access system for an elevator system; and 
         FIGS. 3 a -3 f    illustrate steps in operation of an embodiment of a hoistway access system of an elevator system. 
     
    
    
     DETAILED DESCRIPTION 
     Shown in  FIG. 1  is a schematic of an exemplary traction elevator system  10 . The elevator system  10  includes an elevator car  12  operatively suspended or supported in a hoistway  14  with one or more suspension members  16 , such as ropes or belts. The one or more suspension members  16  interact with one or more sheaves  18  to be routed around various components of the elevator system  10 . The one or more sheaves  18  could also be connected to a counterweight  22 , which is used to help balance the elevator system  10  and reduce the difference in suspension member  16  tension on both sides of a traction sheave  24  during operation. 
     The sheaves  18  each have a diameter  20 , which may be the same or different than the diameters of the other sheaves  18  in the elevator system  10 . At least one of the sheaves could be a traction sheave  24 . The traction sheave  24  is driven by a machine  26 . Movement of traction sheave  24  by the machine  26  drives, moves and/or propels (through traction) the one or more suspension members  16  that are routed around the traction sheave  24 . At least one of the sheaves  18  could be a diverter, deflector or idler sheave. Diverter, deflector or idler sheaves are not driven by the machine  26 , but help guide the one or more suspension members  16  around the various components of the elevator system  10 . While the embodiments are described in relation to elevator systems with suspension members, one skilled in the art will readily appreciate that the present disclosure may be applied to other types of elevator systems, such as those with self-propelled elevator cars lacking suspension members. 
     The elevator system  10  further includes one or more guide rails  28  to guide the elevator car  12  along the hoistway  14 . The elevator car includes one or more guide shoes or rollers  30  interactive with the guide rails  28  to guide the elevator car  12 , and also may include safeties  32  interactive with the guide rail  28  to slow and/or stop motion of the elevator car  12  under certain conditions, such as an overspeed condition. 
     The hoistway  14  includes one or more landing floors  34  at which the elevator car  12  stops to allow ingress and/or egress of passengers from the elevator car  12  through elevator car doors (not shown). The hoistway  14  further includes a pit  36 , defined as the portion of the hoistway  14  below the elevator car  12  when the elevator car  12  is positioned at the lowest landing floor  34  of the hoistway  14 . 
     Referring to  FIG. 2 , the pit  36  is periodically accessed by technicians or other personnel to clean the pit  36  or to retrieve items, such as keys  38  that may inadvertently fall into the pit  36 . To allow for safe access to the pit  36 , the elevator system  10  includes a hoistway entry system  40 . The hoistway entry system  40  includes an access switch  42 , which in some embodiments is located at a lowest landing floor  34  of the elevator system  10 . In other embodiments, the access switch  42  may be located elsewhere, such as a control cabinet of the elevator system  10 , which may be located at any landing floor. The access switch  42  is activated by the technician when it is desired to enter the pit  36 . In some embodiments, the access switch  42  is activated via a triangular key or other means such as a key pad, magnetic card, or the like. The access switch  42  is operably connected to an elevator system controller  46 , which controls operation of the machine  26 . The elevator system controller  46  is also connected to a remote controlled lock  48  at a landing door providing access to the pit  50  and further connected to an electrical or mechanical safety actuation module  52  positioned at the elevator car  12 . 
     Operation of the hoistway entry system  40  will now be described with reference to  FIGS. 3 a -3 f   . In  FIG. 3 a   , a technician  54  desires to enter the pit  36 , and proceeds to the landing floor  34  of the elevator system  10  where the access switch  42  is located. In  FIG. 3 b   , the technician  54 , initiates the hoistway entry system  40  by activating the access switch  42 . Referring to  FIG. 3 c   , when the access switch  42  is activated, the elevator system controller  46  commands the machine  26  to drive the elevator car  12  to an uppermost landing floor  34  of the hoistway  14 , or alternatively to another landing floor  34  that provides a selected volume of space for the technician  54  to access and work in the pit  36 . Next, referring to  FIG. 3 d   , the hoistway entry system  40  activates the safety actuation module  52 , which could be either mechanical or electrical, at the elevator car  12 . The system controller commands the machine  26  to drive the elevator car  12  slowly downwardly in the hoistway  14 , causing the safeties  32  to activate, stopping and holding the elevator car  12  in the hoistway  14  via the car guide rails  28 , to create a safety volume  56  defined by the pit  36  and the elevator car  12  in the hoistway  12 . Alternatively, the elevator car  12  may be driven to any location in the hoistway  14 , such as between landing floors  34 , provided a resulting safety volume  56  below the elevator car  12  is achieved. 
     Referring now to  FIG. 3 e   , the elevator system controller  46  detects that the safeties  32  are engaged, the remote control lock  48  releases the landing door providing access to the pit  50 , and in  FIG. 3 f    the technician  54  can then open the landing door  50  and enter the pit  36  for cleaning of the pit  36  and/or retrieving of items in the pit  36 . When the technician  54  completes operations in the pit  36 , the technician  54  exits the pit  36 , returning to the landing floor  34 . The technician  54  then deactivates the hoistway access system  40  via operation of the access switch  42 , returning the elevator system  10  to normal operation. 
     While the present disclosure has been described in detail in connection with only a limited number of embodiments, it should be readily understood that the present disclosure is not limited to such disclosed embodiments. Rather, the present disclosure can be modified to incorporate any number of variations, alterations, substitutions or equivalent arrangements not heretofore described, but which are commensurate in spirit and/or scope. Additionally, while various embodiments have been described, it is to be understood that aspects of the present disclosure may include only some of the described embodiments. Accordingly, the present disclosure is not to be seen as limited by the foregoing description, but is only limited by the scope of the appended claims.