Patent Publication Number: US-2017362064-A1

Title: Elevator Car and Elevator System

Description:
The invention is related to an elevator car and to an elevator system comprising an apron, in particular a movable apron. The invention is further related to a method of accessing the hoistway of an elevator system by moving an apron of the elevator system. 
     Due to safety requirements elevator cars are provided with aprons extending from the bottom of the elevator car. The aprons are configured for preventing persons from falling into the hoistway in situations in which the landing doors are opened although the elevator car is positioned not exactly at a landing, i.e. not at the same level of height as a landing. Such situation might occur in an emergency rescue operation when releasing passengers which are trapped in a blocked elevator car due to a malfunction of the elevator system, for example. 
     Access to the hoistway is required in some situations, e.g. service personnel needs to enter the hoistway, in particular a pit at the bottom of the hoistway, for repair and/or maintenance purposes. However, an apron blocks such access. Providing means for allowing access to the hoistway, if desired, usually requires space in the hoistway. However, available space in the hoistway is very limited. 
     Therefore, it would be beneficial to allow service personnel to enter the hoistway in a simple way, if desired, but still provide the necessary measures for preventing persons from falling into the hoistway. 
     According to an exemplary embodiment of the invention, an elevator car, which is configured for traveling along a hoistway extending between a plurality of landings, comprises an apron arranged at the bottom of the elevator car. The apron is movable between at least two positions including a blocking position in which the apron extends downward from the bottom of the elevator car blocking access to the hoistway via an area below the elevator car, and an access position, in which the apron allows access to the hoistway via the area below the elevator car. 
     Exemplary embodiments of the invention further include an elevator system comprising an elevator car with a movable apron according to an exemplary embodiment of the invention, and a method of accessing the hoistway of such an elevator system. The method includes the step of moving the apron from its blocking position into its access position. 
     Exemplary embodiments of the invention provide the required safety of preventing persons from falling into the hoistway when the apron is positioned in its blocking position. But they allow easy access to the hoistway when the apron is moved into its access position. 
     Service personnel may enter the hoistway without being blocked by the apron. As a result, maintenance and repair of the elevator system is considerably facilitated without reducing the safety of the elevator system. 
    
    
     
       Exemplary embodiments of the invention will be described in more detail with respect to the enclosed figures: 
         FIG. 1  depicts a schematic view of an elevator system according to an exemplary embodiment of the invention. 
         FIGS. 2 a  and 2 b    schematically depict a configuration according to a first exemplary embodiment with the apron being positioned in a blocking position. 
         FIGS. 3 a  and 3 b    schematically depict a configuration according to the first exemplary embodiment with the apron being positioned in an access position. 
         FIG. 4 a    schematically depicts a second exemplary embodiment with the apron being positioned in a blocking position. 
         FIG. 4 b    schematically depicts the second exemplary embodiment with the apron being positioned in an intermediate position. 
         FIG. 4 c    depicts schematically depicts the second exemplary embodiment with the apron being positioned in an access position. 
         FIG. 1  depicts an elevator system  2  according to an exemplary embodiment of the invention. 
     
    
    
     The elevator system  2  includes an elevator car  6  which is movably suspended within a hoistway  4  by means of at least one tension member  3 . The tension member  3 , for example a rope or belt, is connected to an elevator drive  5 , which is configured for driving the tension member  3  in order to move the elevator car  6  along the height of the hoistway  4  between a plurality of landings  8   a ,  8   b ,  8   c  located on different heights. 
     Each landing  8   a ,  8   b ,  8   c  is provided with a landing door  10 , and the elevator car  6  is provided with a corresponding elevator car door  12  for allowing passengers to transfer between a landing  8   a ,  8   b ,  8   c  and the interior of the elevator car  6  when the elevator car  6  is positioned at the respective landing  8   a ,  8   b ,  8   c.    
     The exemplary embodiment shown in  FIG. 1  uses a 1:1 roping for suspending the elevator car  6 . The skilled person, however, easily understands that the type of the roping is not essential for the invention and that different kinds of roping, e.g. a 2:1 roping, 4:1 roping, etc. are possible as well. The elevator system  2  may use a counterweight (not shown) or not. The elevator drive  5  may be any form of drive used in the art, e.g. a traction drive, a hydraulic drive, or a linear drive. The drive system may use a tension member, like a rope or a belt, or may be a ropeless drive system. The elevator system  2  may have a machine room or may be a machine room-less elevator system. 
     The elevator drive  5  is controlled by an elevator control unit  7  for moving the elevator car  6  between the different landings  8   a ,  8   b ,  8   c.    
     Input to the control unit  7  may be provided via an elevator car control panel  14  provided inside the elevator car  6  and landing control panels  16 , which are provided next to the landing doors  10  on each landing  8   a ,  8   b ,  8   c.    
     The elevator car control panel  14  and the landing control panels  16  may be connected to the elevator control unit  7  by means of electrical lines, which are not shown in  FIG. 1 , in particular by an electric bus, or by wireless connections. 
     Alternatively or additionally, commands may be input into the elevator control unit  7  via mobile devices (not shown), e.g. smartphones, carried by the passengers. In this case, the elevator control unit  7  may be provided with at least one communication unit  17 , which is configured for indirectly (including, but not limited to, via the internet or a cellular network) or directly (including, but not limited to via WiFi, Bluetooth, or other known wireless communication methods, such as 1G, 2G (GSM), 3G, 4G (LTE), 5G, and future generations of cellular data communications) wirelessly communicating with the mobile device(s). Additional communication units (not shown) may be provided at the landings  10 . 
     An indicator element  34  is arranged in a lower portion of the hoistway  14 . The functionality of said indicator element  34  will be described in more detail further below. 
     In case the bottom  9  of the elevator car  6  is not positioned exactly at the same level of height as the floor  13   a ,  13   b ,  13   c  of the closest landing  8   a ,  8   b ,  8   c , a gap is formed between the bottom  9  of the elevator car  6  and the floor  13   a ,  13   b ,  13   c  of the respective landing  8   a ,  8   b ,  8   c . In order to prevent persons from falling into the hoistway  4  in case the landing door  10  is opened in such a situation, e.g. for releasing passenger which are trapped within the elevator car  6 , an apron  20  extends basically vertically from the bottom  9  of the elevator car  6  in an area below the elevator car door  12 . 
     However, there might be situations in which it is desirable to access the hoistway  4  via the landing door(s)  10 , e.g. in case the elevator car  6  is positioned in the vicinity of the lowest landing  8   a  and service personnel needs to enter a pit  11 , which is formed at the bottom of the hoistway  4 . 
     According to exemplary embodiments of the invention, the apron  20  is movable from a blocking position, in which the apron  20  blocks the area below the elevator car  6  and does not allow to access the hoistway  4  via the landing door  10 , into an access position, in which the apron  20  does not block the area below the elevator car  6 , but allows access to the hoistway  4  via the landing door  10 . 
     Exemplary embodiments of the invention are described in more detail with reference to the following figures, respectively depicting an area close to the bottom  9  and below the elevator car  6 , in a situation in which the elevator car  6  is close to the lowermost landing  8   a , but in a position with some distance above the floor  13   a  of the landing  8   a.    
       FIGS. 2 a  and 3 a    show side-views, while  FIGS. 2 b  and 3 b    show front views of the area close to the bottom  9  and below the elevator car  6 , respectively. 
       FIGS. 2 a  and 2 b    depict a configuration in which the apron  20  is positioned in its blocking position, while  FIGS. 3 a  and 3 b    depict a configuration in which the apron  20  is positioned in its access position, respectively. 
     According to the exemplary embodiment shown in  FIGS. 2 a  to 3 b   , the apron  20  is supported by means of two telescopic extensions  22  located at positions left and right from the center of the elevator car door  12  and extending from the bottom  9  of the elevator car  6  basically vertically parallel to each other. The telescopic extensions  22  are configured to allow moving the apron  20  linearly in a basically vertical direction between the upper blocking position shown in  FIGS. 2 a  and 2 b   , in which the apron  20  blocks the area below the bottom  9  of the elevator car  6 , and the lower access position shown in  FIGS. 3 a  and 3 b   , in which the apron  20  does not block the area below the bottom  9  of the elevator car  6 . When the apron  20  is positioned in said lower access position, an opening  25 , which is defined by the bottom  9  of the elevator car  6 , the upper edge of the apron  20  and the two vertically extending telescopic extensions  22 , is formed. A person may enter the hoistway  4  from the landing  8   a  via said opening  25 . 
       FIGS. 2 a  to 3 b    show further, optional features: 
     Steps  24  may be formed within the apron  20  or at the side of the apron  20  facing the hoistway  4 . Such steps  24  allow a person entering the hoistway  4  to climb down to the bottom of the hoistway  14  (pit  11 ) easily without using an additional ladder (not shown) or a similar device. The access to such a ladder might be difficult or even impossible when the elevator car  6  is in a position which allows to reach the elements at the bottom of the elevator car when standing in the pit  11 . 
     The steps  24  in particular may be provided as recesses or openings formed within the apron  20 . In an alternative configuration, the steps  24  may be provided as webs formed at the side of the apron  20  facing the hoistway  4 . 
     In addition to the steps  24 , at least one handrail (not shown) may be provided at the apron  20  allowing a person using the steps  24  to hold on when descending into and/or ascending from the pit  11 . 
     For facilitating the movement of the apron  20  from its access position into its blocking position, at least one handle  26  may be provided at the top of the apron  20  or at the side of the apron  20 , in particular at the side of the apron  20  facing the landings  8   a ,  8   b ,  8   c.    
     For preventing an undesired movement of the apron  20 , an additional blocking mechanism may be provided. In case the apron  20  is supported by telescopic extensions  22 , as it is shown in  FIGS. 2 a  to 3 b   , the blocking mechanism may include bolts or screws  28  extending through corresponding openings formed within the telescopic extensions  22  and thereby blocking any movement of the telescopic extensions  22 . The bolts or screws  28  are removed (pulled out) from the openings, in order to allow a desired movement of the apron  20  from its blocking position into its access position. In order to prevent an undesired/accidental removal of the bolts or screws  28 , the bolts or screws  28  may be secured within the openings by means of splints (not shown) or similar securing elements. 
     For preventing an unauthorized release of the blocking mechanism, the blocking mechanism may be provided with an additional locking mechanism. For example, specially formed screws  28 , which are releasable only by means of a special tool, may be employed. Alternatively or additionally, at least one lock may be associated with at least one of the bolts or screws  28  such that the respective bolt or screw  28  is removable only after the lock has been unlocked by means of a matching key. 
     In situations in which the elevator car  6  is positioned at a higher landing  8   b ,  8   c  moving the apron  20  out of its blocking position would result in a dangerous situation. The locking mechanism and/or the blocking mechanism therefore may be configured such that they may be unlocked/unblocked only in case the elevator car  6  is positioned within a predetermined distance from the lowest landing  8   a . This prevents creating a dangerous situation by moving the apron  20  out of its blocking position while the elevator car  6  is positioned at or close to one of the higher landings  8   b ,  8   c.    
     Allowing the locking mechanism and/or the blocking mechanism to be unlocked/unblocked only in case the elevator car  6  is positioned within a predetermined distance from the lowest landing  8   a  may be realized for example by mechanical interaction of the locking mechanism and/or the blocking mechanism with a corresponding indicator element  34  (see  FIG. 1 ), which is arranged in a lower portion of the hoistway  4  for indicating that the apron  20  may be moved into its access position when the elevator car  6  is located next to said indicator element  34  in said lower portion of the hoistway  4 . 
     Additionally or alternatively the locking mechanism and/or the blocking mechanism may comprise electromagnetic elements (not shown) such as solenoids electrically connected with the elevator control unit  7  and configured for releasing the locking mechanism and/or the blocking mechanism (only) in case the elevator car  6  is positioned within a predetermined distance from the lowest landing  8   a.    
     Such electromagnetic elements further may be configured for releasing the locking mechanism and/or the blocking mechanism only after authorized service personnel has been identified by means of a key, a key card, and/or by entering a secret code or similar. 
     The movable apron  20  may be provided with at least one sensor  32  which is configured for detecting the actual position of the apron  20  and reporting it to the elevator control unit  7 . In consequence, the elevator control unit  7  may allow the elevator car  6  to move only in case the apron  20  is detected as being positioned in its blocking position. This enhances the safety of the elevator system  2 , as any movement of the elevator  6  is prevented while the apron  20  is not positioned in its blocking position. 
       FIGS. 4 a , 4 b , and 4 c    illustrate a movable apron  20  according to a second embodiment of the invention in its blocking position ( FIG. 4 a   ), in its access position ( FIG. 4 c   ) and in an intermediate position ( FIG. 4 b   ), respectively. 
     According to said second embodiment, the apron  20  is movable between its blocking position and its access position in a pivoting motion in which the apron  20  rotates around a horizontally extending axle  30  which is provided in some distance below the bottom of the elevator car  6 . 
     When positioned in its blocking position, the apron  20  extends basically vertically upwards from the horizontal axle  30 , as it is shown in  FIG. 4   a.    
     After being pivoted ( FIG. 4 b   ) around the axle  30  into its access position, the apron  20  extends basically vertically downwards from the horizontal axle  30  providing an opening  25  between the axle  30  and the bottom of the elevator car  6  ( FIG. 4 c   ). Persons may enter into the hoistway  4  via said opening  25 . 
     The movable apron  20  according to the second embodiment may be provided with appropriate blocking and/or locking mechanisms and/or detecting means which are configured for detecting the actual position of the apron  20 , as it has been described with reference to the first embodiment, as well. 
     The movable apron  20  further may be provided with an appropriate tool (not shown), e.g. with a rope or a rod, which is configured for facilitating the movement of the apron  20  from the access position back into the blocking position. 
     A number of optional features are set out in the following. These features may be realized in particular embodiments, alone or in combination with any of the other features. 
     In an embodiment, the elevator car comprises at least one elevator car door and the apron may be arranged below said at least one elevator car door. An apron which is arranged below said at least one elevator car door is very effective in preventing persons exiting from the elevator car via the elevator car door from falling into the hoistway through a gap formed below the bottom of the elevator car. 
     In an embodiment, the apron may be configured for moving linearly between the blocking position and the access position. A linear motion allows to move the apron between the blocking position and the access position conveniently. 
     In an embodiment, the elevator car may comprise a telescopic mechanism which is configured for supporting the apron and for moving the apron between the at least two positions. A telescopic mechanism provides a convenient and reliable means for allowing a linear motion of the apron. 
     In an embodiment, the apron may be configured for moving between the blocking position and the access position in a pivoting motion. This provides a simple alternative to moving the apron linearly between the blocking position and the access position, which may be installed at low costs. 
     In an embodiment, the elevator car may further comprise a releasable blocking mechanism which allows to prevent the movement of the apron. Such a blocking mechanism enhances the safety of the elevator system, as an undesired and/or accidental movement of the apron out of its blocking position is reliably prevented. 
     In an embodiment, the elevator car may further comprise a locking mechanism which is configured for preventing an unauthorized release of the releasable blocking mechanism. Such a locking mechanism, which may include a lock, enhances the safety of the elevator system, as any movement of the apron out of its blocking position by unauthorized/unqualified persons is reliably prevented. 
     In an embodiment, the apron may be movable into the access position only when the elevator car is positioned not more than a predetermined distance spaced apart from the lowest landing. Thus, a method of accessing the hoistway includes moving the elevator car within a predetermined distance from the lowest landing. This enhances the safety of the elevator system, as any movement of the apron is prevented when the elevator car is located next to a higher landing. 
     In an embodiment, the elevator car is blocked from moving along the hoistway when the apron is not positioned in its blocking position. This enhances the safety of the elevator system even further. 
     In an embodiment, the movable apron may be provided with at least one sensor which is configured for detecting the actual position of the apron and for reporting it to the elevator control unit. The elevator control unit may be configured to allow the elevator car to move only in case the apron is detected as being positioned in its blocking position. This further enhances the safety of the elevator system. 
     In an embodiment, at least one step may be formed in or at the apron. Such at least one step facilitates the access to the hoistway when the apron is positioned in its access position. Additionally to the at least one step, a handrail (not shown) may be provided at the apron for allowing a person using the at least one step to hold on for a safe descent into and/or a safe ascent from the pit. 
     In an embodiment of an elevator system, a pit is formed at the bottom of the hoistway and the apron is movable from its blocking position into its access position for providing access to the pit. This facilitates maintenance and repair of the elevator system. 
     While the invention has been described with reference to exemplary embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition many modifications may be made to adopt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed, but that the invention include all embodiments falling within the scope of the claims. 
     REFERENCES 
     
         
           2  elevator system 
           3  tension member 
           4  hoistway 
           5  drive 
           6  elevator car 
           7  elevator control unit 
           8   a ,  8   b ,  8   c  landing 
           9  bottom of the elevator car 
           10  landing door 
           11  pit 
           12  elevator car door 
           13   a ,  13   b ,  13   c  floor 
           14  elevator car control panel 
           16  landing control panel 
           20  apron 
           22  extension 
           24  step 
           26  handle 
           28  bolt/screw 
           30  axle 
           32  sensor 
           34  indicator element