Abstract:
An elevator car is constructed and arranged to move along a hoistway. The car includes a cab support from below by a platform. A vertical member is connected to the platform via a flex joint and extends upward from platform for further elevator cab support. The flex joint facilitates cab isolation from vibration and noise.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims priority to U.S. Provisional Patent Application No. 62/212,815, filed Sep. 1, 2015, the entire contents of which is incorporated herein by reference. 
     
    
     BACKGROUND 
       [0002]    The present disclosure relates to elevator systems, and more particularly to cab isolation of an elevator car. 
         [0003]    Self-propelled elevator systems, also referred to as ropeless elevator systems, are useful in certain applications (e.g., high rise buildings) where the mass of the ropes for a roped system is prohibitive and/or there is a need for multiple elevator cars in a single hoistway. Elevator cars typically include a cab and a carriage that supports and moves with the cab. The elevator system may further include multiple thrust producing actuators that are electromagnetically coupled to guidance and propulsion devices in the hoistway that may have relative misalignments. It is desirable for the cab-supporting carriage to accommodate such misalignments. It may further desirable to mechanically isolate the cab from noise and vibration that may be transmitted by or through the carriage and to the cab for ride comfort and/or propulsion efficiency. 
       SUMMARY 
       [0004]    An elevator car constructed and arranged to move along a hoistway, the elevator car according to one, non-limiting, embodiment of the present disclosure including a cab; a platform disposed below the cab; a first vertical member extending upward from the platform; and a first flex joint connected to and extending between the platform and the first vertical member. 
         [0005]    Additionally to the foregoing embodiment, the elevator car includes a first isolator connected to and extending between the platform and the cab. 
         [0006]    In the alternative or additionally thereto, in the foregoing embodiment, the elevator car includes a second isolator connected to and extending between the first vertical member and the cab. 
         [0007]    In the alternative or additionally thereto, in the foregoing embodiment, the elevator car includes a second isolator connected to and extending between the first vertical member and a first side of the cab, and wherein the second isolator is proximate to a top of the cab. 
         [0008]    In the alternative or additionally thereto, in the foregoing embodiment, the elevator car includes a crosshead member disposed above and extending over the cab; and a second flex joint connected to and extending between the first vertical member and the crosshead member. 
         [0009]    In the alternative or additionally thereto, in the foregoing embodiment, the elevator car includes a first guide device supported by the first vertical member for guiding the elevator car within the hoistway. 
         [0010]    In the alternative or additionally thereto, in the foregoing embodiment, the first guide device is at least one roller. 
         [0011]    In the alternative or additionally thereto, in the foregoing embodiment, the elevator car includes a second vertical member with the first vertical member disposed adjacent to a first side of the cab and the second vertical member disposed adjacent to an opposite second side of the cab; and a third flex joint connected to and extending between the platform and the second vertical member. 
         [0012]    In the alternative or additionally thereto, in the foregoing embodiment, the elevator car includes a fourth flex joint connected to and extending between the second vertical member and the crosshead member. 
         [0013]    In the alternative or additionally thereto, in the foregoing embodiment, the elevator car includes a first isolator connected to and extending between the platform and the cab; a second isolator connected to and extending between the first vertical member and the cab; and a third isolator connected to and extending between the second vertical member and the cab. 
         [0014]    In the alternative or additionally thereto, in the foregoing embodiment, at least one of the first, second and third isolators is a spring. 
         [0015]    In the alternative or additionally thereto, in the foregoing embodiment, at least one of the first, second and third isolators is a resilient puck. 
         [0016]    In the alternative or additionally thereto, in the foregoing embodiment, the second and third isolators are proximate to a top of the cab. 
         [0017]    In the alternative or additionally thereto, in the foregoing embodiment, the elevator car includes a first plurality of permanent magnets engaged to and distributed along the first vertical member for elevator car propulsion; and a second plurality of permanent magnets engaged to and distributed along the second vertical member for elevator car propulsion. 
         [0018]    In the alternative or additionally thereto, in the foregoing embodiment, the elevator car includes a first guide device supported by the first vertical member for guiding the elevator car within the hoistway; and a second guide device supported by the second vertical member for guiding the elevator car within the hoistway. 
         [0019]    In the alternative or additionally thereto, in the foregoing embodiment, the elevator car is a ropeless elevator car. 
         [0020]    In the alternative or additionally thereto, in the foregoing embodiment, the flex joints have two degrees of freedom including a translational direction and a rotational direction. 
         [0021]    In the alternative or additionally thereto, in the foregoing embodiment, the translational direction and the rotational directions are orientated within a common imaginary plane. 
         [0022]    In the alternative or additionally thereto, in the foregoing embodiment each flex joint includes at least one stopper for limiting translational motion and at least one snubber for limiting rotational motion. 
         [0023]    In the alternative or additionally thereto, in the foregoing embodiment, the first flex joint includes a casing engaged to one of the platform and the vertical member, a piston head arranged to reciprocate in a bore defined by the casing, and a shaft pivotally engaged between the piston head and the other of the platform and the vertical member. 
         [0024]    A ropeless elevator system according to another, non-limiting, embodiment includes an elevator car constructed and arranged to move along a hoistway, the elevator car including a cab, a platform disposed beneath the cab, a vertical member extending upward from the platform and a first flex joint engaged between the platform and the vertical member for flexing of the platform with respect to the vertical member; and a linear propulsion system carried between the hoistway and the vertical member for propelling the elevator car. 
         [0025]    Additionally to the foregoing embodiment, the elevator car includes a first isolator extending between the platform and the cab for attenuating energy. 
         [0026]    In the alternative or additionally thereto, in the foregoing embodiment, the elevator car includes a cross head member extending over the cab, and a second flex joint engaged between the vertical member and the crosshead member. 
         [0027]    In the alternative or additionally thereto, in the foregoing embodiment, the elevator car includes a second isolator extending between the vertical member and the cab. 
         [0028]    In the alternative or additionally thereto, in the foregoing embodiment, the first flex joint has a non-linear force profile. 
         [0029]    The foregoing features and elements may be combined in various combinations without exclusivity, unless expressly indicated otherwise. These features and elements as well as the operation thereof will become more apparent in light of the following description and the accompanying drawings. However, it should be understood that the following description and drawings are intended to be exemplary in nature and non-limiting. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0030]    Various features will become apparent to those skilled in the art from the following detailed description of the disclosed non-limiting embodiments. The drawings that accompany the detailed description can be briefly described as follows: 
           [0031]      FIG. 1  depicts a multicar elevator system in an exemplary embodiment; 
           [0032]      FIG. 2  is a top down view of an elevator car and portions of a linear propulsion system in an exemplary embodiment; 
           [0033]      FIG. 3  is a schematic of the linear propulsion system; 
           [0034]      FIG. 4  is a side view of the elevator car; 
           [0035]      FIG. 5  is a cross section of an upper flex joint engaged between a crosshead member and a vertical member of the elevator car; and 
           [0036]      FIG. 6  is a cross section of a lower flex joint engaged between a platform and the vertical member of the elevator car. 
       
    
    
     DETAILED DESCRIPTION 
       [0037]      FIG. 1  depicts a self-propelled or ropeless elevator system  20  in an exemplary embodiment that may be used in a structure or building  22  having multiple levels or floors  24 . Elevator system  20  includes a hoistway  26  having boundaries defined by the structure  22  and at least one car  28  adapted to travel in the hoistway  26 . The hoistway  26  may include, for example, three lanes  30 ,  32 ,  34  each extending along a respective centerline  35  with any number of cars  28  traveling in any one lane and in any number of travel directions (i.e., up and down in the lanes and horizontally along centerline  35  in the transfer stations  36 ,  38 ). For example and as illustrated, the cars  28  in lanes  30 ,  34 , may travel in an up direction and the cars  28  in lane  32  may travel in a down direction. 
         [0038]    Above the top floor  24  may be an upper transfer station  36  that facilitates horizontal motion to elevator cars  28  for moving the cars between lanes  30 ,  32 ,  34 . Below the first floor  24  may be a lower transfer station  38  that facilitates horizontal motion to elevator cars  28  for moving the cars between lanes  30 ,  32 ,  34 . It is understood that the upper and lower transfer stations  36 ,  38  may be respectively located at the top and first floors  24  rather than above and below the top and first floors, or may be located at any intermediate floor. Yet further, the elevator system  20  may include one or more intermediate transfer stations (not illustrated) located vertically between and similar to the upper and lower transfer stations  36 ,  38 . 
         [0039]    Referring to  FIGS. 1 through 3 , cars  28  are propelled using a linear propulsion system  40  having at least one, fixed, primary portion  42  (e.g., two illustrated in  FIG. 2  mounted on opposite sides of the car  28 ), moving secondary portions  44  (e.g., two illustrated in  FIG. 2  mounted on opposite sides of the car  28 ), and a control system  46  (see  FIG. 4 ). The primary portion  42  includes a plurality of windings or coils  48  mounted at one or both sides of the lanes  30 ,  32 ,  34  in the hoistway  26 . Each secondary portion  44  may include two rows of opposing permanent magnets  50 A,  50 B mounted to the car  28 . Primary portion  42  is supplied with drive signals from the control system  46  to generate a magnetic flux that imparts a force on the secondary portions  44  to control movement of the cars  28  in their respective lanes  30 ,  32 ,  34  (e.g., moving up, down, or holding still). The plurality of coils  48  of the primary portion  42  are generally located between and spaced from the opposing rows of permanent magnets  50 A,  50 B. It is contemplated and understood that any number of secondary portions  44  may be mounted to the car  28 , and any number of primary portions  42  may be associated with the secondary portions  44  in any number of configurations. 
         [0040]    Referring to  FIG. 3 , the control system  46  may include power sources  52 , drives  54 , buses  56  and a controller  58 . The power sources  52  are electrically coupled to the drives  54  via the buses  56 . In one non-limiting example, the power sources  52  may be direct current (DC) power sources. DC power sources  52  may be implemented using storage devices (e.g., batteries, capacitors), and may be active devices that condition power from another source (e.g., rectifiers). The drives  54  may receive DC power from the buses  56  and may provide drive signals to the primary portions  42  of the linear propulsion system  40 . Each drive  54  may be a converter that converts DC power from bus  56  to a multiphase (e.g., three phase) drive signal provided to a respective section of the primary portions  42 . The primary portion  42  is divided into a plurality of modules or sections, with each section associated with a respective drive  54 . 
         [0041]    The controller  58  provides control signals to each of the drives  54  to control generation of the drive signals. Controller  58  may use pulse width modulation (PWM) control signals to control generation of the drive signals by drives  54 . Controller  58  may be implemented using a processor-based device programmed to generate the control signals. The controller  58  may also be part of an elevator control system or elevator management system. Elements of the control system  46  may be implemented in a single, integrated module, and/or be distributed along the hoistway  26 . 
         [0042]    Referring to  FIGS. 2 and 4 , the elevator car  28  may include a cab  60  supported by a carriage  62 . The cab  60  includes a bottom  64 , a top  66  and opposite sides  68 ,  70  with cab doors  72  located there-between. The carriage  62  may include a platform  74  located beneath the bottom  64  of the cab  60 , a first substantially vertical member  76  projecting upward from the platform  74  and adjacent to the first side  68  of the cab  60 , a second substantially vertical member  78  extending upward from the platform  74  and adjacent to the second side  70 , and a crosshead member  80  located above the top  66  of the cab  60  and extending between the vertical members  76 ,  78 . 
         [0043]    The platform  74  may generally shadow the bottom  64  of the cab  60  (i.e., substantially square in shape like the bottom and about the same size or larger). A first plurality of isolators  82  of the carriage  62  may extend between and may be engaged to the bottom  64  of the cab  60  and the platform  74 . Although two isolators  82  are illustrated in  FIG. 4 , any number of isolator  82  may extend between the platform  74  and the cab bottom  64 . For example, there may be an isolator  82  generally located at each corner of the cab  60 . Alternatively and depending upon the shape of the platform  74 , there may be only two isolators  82  with each one proximate to the respective vertical members  76 ,  78 . A second plurality of isolators  84  may extend between and may be engaged to the sides  68 ,  70  of the cab  60  and the respective vertical members  76 ,  78 . The isolators  84  may further be located near or proximate to the top  66  of the cab  60 . 
         [0044]    The isolators  82 ,  84  are configured to isolate the cab  60  from the carriage  62  thereby minimizing or eliminating at least in-part the flow of acoustic energy into the cab. As non-limiting examples, the isolators  82 ,  84  may be springs, or, may be resilient pucks that may be made of a rubber-like material. Different types of isolators may be used at different locations depending upon a particular need and/or for accommodating flexibility at the specific location. 
         [0045]    The carriage  62  may further include a first plurality of flex joints  86  (i.e., two illustrated in  FIG. 4 ) extending between and connecting the vertical members  76 ,  78  to the platform  74 . A second plurality of flex joints  88  (i.e. two illustrated in  FIGS. 2 and 4 ) may generally connect the vertical members  76 ,  78  to respective opposite ends of the crosshead member  80 . The flex joints  86 ,  88  facilitate limited and controlled motion between the platform  74  and members  76 ,  78 ,  80  while constraining other degrees of freedom to properly transmit desired forces. As non-limiting examples, the flex joints  86 ,  88  may be made of a bendable, resilient, and structurally sufficient material and/or may be mechanical devices that allow controlled translational and/or rotational motion between carriage components. Further examples of flex joints may include hinge-like devices, ball and socket joints, linear translational joints and others. 
         [0046]    The carriage  62  may also include guide devices  90  that may be supported by each vertical member  76 ,  78  for, at least in-part, guiding the carriage  62  along the vertically extending primary portions  42  of the linear propulsion system  40 . As one, non-limiting, example, the guide devices  90  may be rollers secured to the top and bottom ends of the vertical members  76 ,  78  (only the top shown in  FIG. 4 ). It is further contemplated that such guide devices  90  may also be secured to the platform  74  and/or the crosshead member  80  or any combination thereof. The vertical members  76 ,  78  may also support the magnets  50 A,  50 B of the secondary portions  44  of the linear propulsion system  40 . It is understood that the orientations of adjacent structures such as guide devices  90  and secondary portions  44 , and the forces produced by the linear propulsion system  40  may impact the choice and locations of the flex joints  86 ,  88  and the isolators  82 ,  84 . 
         [0047]    Referring to  FIG. 5 , a non-limiting example of the upper flex joint  88  may include a casing  92 , a piston head  94 , and a piston shaft  96  configured to facilitate two degrees of freedom between the crosshead member  80  and the vertical member  76  (see arrows  98 ,  100 ). The casing  92  may be rigidly engaged to the crosshead member  80  or other rigid structure engaged to the crosshead member. The piston head  94  is arranged to linearly translate within a bore defined by the casing  92 , and opposite ends  102 ,  104  of the shaft  96  may be pivotally connected to the respective head  94  and the vertical member  76  (i.e., or other structure rigidly engaged to the vertical member). 
         [0048]    Referring to  FIG. 6 , a non-limiting example of the lower flex joint  86  may include a casing  106 , a piston head  108 , and a piston shaft  110  configured to facilitate two degrees of freedom between the platform  74  and the vertical member  76  (see arrows  112 ,  114 ). The casing  106  may be rigidly engaged to the platform  74  or other rigid structure engaged to the platform. The piston head  108  is arranged to linearly translate within a bore defined by the casing  106 , and opposite ends  116 ,  118  of the shaft  110  may be pivotally connected to the respective head  108  and the vertical member  76  (i.e., or other structure rigidly engaged to the vertical member). 
         [0049]    In operation of the elevator car  28 , the guide devices  90  may assist in maintaining two consistent gaps located, for example on both sides of the coils  48  of the primary portion  42 , and respectively between the first permanent magnet  50 A and the coil  48  for the first gap, and between the second permanent magnet  50 B and the coil  48  for the second gap. As previously described, two primary portions  42  may be mounted on opposite sides of each lane  30 ,  32 ,  34 . In instances where the opposing primary portions  42  are not aligned to one-another within preferred tolerances, excessive drag or restrictive forces may be placed on the guide devices  90  to maintain the consistent gaps. The flex joints  86 ,  88  may operate to eliminate or minimize excessive drag upon the guide devices  90  by facilitating multiple degrees of motion (two illustrated) between the vertical members  76 ,  78  and the platform  74  and crosshead member  80  of the carriage  62 . That is, the carriage  62  is controllably capable of distortion and/or twisting to maintain consistent gaps and minimize drag upon the guide devices  90 . 
         [0050]    More specifically, the flex joints  86 ,  88  may be capable of two degrees of freedom which may include respective translational directions  98 ,  112  and rotational directions  100 ,  114 . All directions  98 ,  100 ,  112 ,  114  may be substantially orientated along a common imaginary plane (not shown) that is substantially normal to the carriage  62 . More specifically, the translational direction  98 ,  112  may be substantially parallel to one another and normal to the respective crosshead member  80  and platform  74 . The rotational directions  100 ,  114  may generally be about the pivot axis where the respective shafts  96 ,  110  connect to the vertical members  76 ,  78 . The axis of the flex joint degrees of freedom may be configured to minimize vibrational forces caused by guide rail installation alignment imperfections while also maintaining adequate structural rigidity as required by the propulsion system  40 . 
         [0051]    The flex joints  86 ,  88  may further have a tailored force verse deflection curve characterized by a low stiffness for small motions and a higher stiffness as the motion increases (i.e. a nonlinear force profile). As one, non-limiting, example, the translational stiffness may be achieved using a pneumatic cylinder to achieve the low stiffness in the flexibility region and hard stoppers  120  that restrict the amount of translational motion along directions  98 ,  112 . As one, non-limiting, example, the rotational stiffness may be facilitated by a flexible revolute joint  122  with snubbers  124  that limit the amount of rotation. The flexing capability of the carriage  62  may be designed to be relatively small and may accommodate guide rail and primary misalignments in the lanes  30 ,  32 ,  34 . For larger deflections the force levels may increase to accommodate potential severe operational loading conditions that may not be typical of normal running conditions. 
         [0052]    While the present disclosure is 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 without departing from the spirit and scope of the present disclosure. In addition, various modifications may be applied to adapt the teachings of the present disclosure to particular situations, applications, and/or materials, without departing from the essential scope thereof. The present disclosure is thus not limited to the particular examples disclosed herein, but includes all embodiments falling within the scope of the appended claims.