Abstract:
An elevator door includes a fast panel and one or more successively slower panels, wherein each panel has a front surface, a parallel rear surface and a lagging surface interconnecting the front surface and rear surface. The lagging surface of a successively faster panel is accommodated between the front surface and the rear surface of a successively slower panel when the door is in its fully open position. With this arrangement, the panels can be accommodated one inside the other when the door is in its fully open position and consequently the depth of the telescopic door can be reduced significantly.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to elevator doors and, in particular, to elevator doors having a plurality of horizontally-sliding panels and a synchronisation mechanism to control simultaneous movement of the panels. 
       BACKGROUND OF THE INVENTION 
       [0002]    In a conventional elevator a one or more telescopic doors are used to to close and open a opening in a shaft wall. The door is generally composed of a plurality of identical panels supported via rollers on one or more overhead tracks. Each panel is connected to a cable and pulley system located above the door to endure synchronous movement of panels. 
       SUMMARY OF THE INVENTION 
       [0003]    An objective of the present invention is to reduce the material involved in the manufacture of telescopic elevator doors and thereby the associated cost of elevator doors. Accordingly, the invention provides an elevator door comprising a fast panel and one or more successively slower panels, wherein each panel has a front surface, a parallel rear surface and a lagging surface interconnecting the front surface and rear surface. The lagging surface of a successively faster panel is accommodated between the front surface and the rear surface of a successively slower panel when the door is in its fully open position. With this arrangement, the panels can be accommodated one inside the other when the door is in its fully open position and consequently the depth of the telescopic door can be reduced significantly. 
         [0004]    The invention is particularly useful for the modernization of existing elevator installations having a swing door at the landing since the depth of the swing door is significantly smaller than that of a conventional telescopic elevator door. 
         [0005]    Preferably, the front surface, the parallel rear surface and the lagging surface of the or each slower panel forms a J-shaped profile. 
         [0006]    Preferably, the panels are fabricated from sheet metal. 
         [0007]    The elevator door may include a first synchronous linkage mechanism incorporated within a depth of the door as defined by the front surface and rear surface of the slowest panel. 
         [0008]    More preferably, the first synchronous linkage mechanism comprises a series of links extending alternatively upwards and downwards between a first pivot point mounted to a door frame and a further pivot point mounted to the fast panel. Each successively slower panel is pivotally mounted to intermediate pivot points on intermediate links of the synchronous linkage mechanism. 
         [0009]    The elevator door can further comprise a second synchronous linkage mechanism wherein the second synchronous linkage mechanism is identical to the first synchronous linkage mechanism but vertically displaced thereform and further comprising a bar to interconnect corresponding points on both linkage mechanisms. 
     
    
     
       DESCRIPTION OF THE DRAWINGS 
         [0010]    The present invention is hereinafter described by way of specific examples with reference to the accompanying drawings in which: 
           [0011]      FIG. 1  is a horizontal cross-section of an elevator shaft; 
           [0012]      FIG. 2A  is a cross-sectional view of an elevator door according to a first embodiment of the present invention in its fully open; 
           [0013]      FIG. 2B  illustrates the door of  FIG. 2A  in a fully closed position; 
           [0014]      FIG. 3  is a cross-sectional view of the telescopic landing door of  FIG. 1  incorporating a synchronous linkage mechanism according to the invention; 
           [0015]      FIG. 4  is a schematic of the telescopic landing door of  FIG. 3  in its closed position; and 
           [0016]      FIG. 5  shows the landing door of  FIG. 4  as it opens. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0017]      FIG. 1  shows a horizontal cross-section of an elevator shaft  1  arranged within a building. The shaft  1  is bound by a rear wall  2 , two side walls  3  and a front wall  4 . An elevator car C is arranged to travel vertically within the shaft  1 . At each floor or landing  5  of the building an opening  6  is provided in the front wall  4  of the shaft  1  to enable passengers to migrate between the elevator car and the landing  5 . Two telescopic doors  7  and  8  are arranged to the left and to the right of the opening  6  respectively to close laterally across the opening  6  and thereby prevent entry to the shaft  1  when the car is not present at a specific landing  5 . In the open position as shown, each of the telescopic doors  7  and  8  have a width W and a depth D which corresponds substantially to the depth of the front wall  4  of the shaft  1 . 
         [0018]    To avoid unnecessary repetition, the following description concentrates almost exclusively on the telescopic door  7  arranged to the left of the opening  6 . However, it will be appreciated that both doors  7  and  8  are symmetrical with and mirror images of each other. 
         [0019]    To facilitate the interchange of the description between the doors  7  and  8 , instead of describing a component as being to the left or right, the term “leading” has been used extensively to describe a component that is foremost in the lateral closing direction of the door  7  or  8  and conversely the term “lagging” to describe a component that is hindmost in the closing direction. The front and rear transverse directions are common to both doors  7  and  8 . 
         [0020]      FIG. 2A  is a cross-sectional view of the telescopic landing door  7  of  FIG. 1  and illustrates in particular the arrangement of the associated door panels  11 ,  12  and  13  in their stacked or stored position so as to permit passenger to pass through the opening  6  in the shaft wall  4 . 
         [0021]    In closing, although all of the panels  11 ,  12 , and  13  move laterally across the opening  6  in the shaft wall  4  at the same time, they travel at different but proportional speeds so that the fast panel  13  travels furthest across the opening  6  and is trailed successively by the intermediate panel  12  and the slow panel  11 , respectively. This movement of the panels  11 ,  12  and  13  is achieved by a synchronous linkage mechanism  50  which will be described later with reference to  FIGS. 3-5 . 
         [0022]    In the fully closed position, as shown in  FIG. 2B , a leading surface  13 . 4  of the fast panel  13  meets the leading surface of the corresponding fast panel from the other door  8  at the center of the opening  6 . 
         [0023]    In addition to the panels  11 ,  12  and  13 , the door  7  further comprises a stationary door frame or post  10 . The post  10  is manufactured from sheet metal and has a generally L-shaped profile. The transverse limb  10 . 1  of the post  10  is attached in conventional manner to an edge  4 . 1  of the front wall  4  of the shaft  1 . The lateral limb forms the front surface  10 . 2  of the post  10  and effectively shields the panels  11 ,  12  and  13  from the landing  5  when the door  7  is in the open position as shown in  FIG. 2A . A double-fold  10 . 3  at the free, leading edge of the front surface  10 . 2  provides a channel to the rear of the front surface  10 . 2 . 
         [0024]    The slow panel  11  is manufactured from sheet metal and has a generally angular, J-shaped profile comprising a lateral rear surface  11 . 1 , a parallel front surface  11 . 3  and an interconnecting, transverse, lagging surface  11 . 2 . As with the post  10 , a double-fold  11 . 4  is provided at the leading edge of the front surface  11 . 3 . A vertical channel  11 . 5  is mounted at the lagging edge of the front surface  11 . 3  and projects forwards therefrom. The channel  11 . 5  has a transposed configuration to the double-fold  10 . 3  of the door post  10  so that with the door  7  in the fully closed position, as shown specifically in  FIG. 2B , the double-fold  10 . 3  of the door post  10  is at least partially accommodated within the channel  11 . 5  of the slow door panel  11 . This arrangement not only prevents a person on the landing  5  from prying the post  10  and the slow panel  11  apart but also prevents the slow panel  11  from over-travelling as the door  7  closes. Additionally, the channel  11 . 5  also provides added stiffness and rigidity to the panel  11 . 
         [0025]    As the intermediate panel  12  is essentially identical to the slow panel  11 , further specific description of the intermediate panel  12  is superfluous. However, one important exception is that the depth of the intermediate panel  12 , as defined by the transverse, lagging surface  12 . 2 , is smaller than the corresponding depth of the slow panel  11 . Again, a vertical channel  12 . 5  on the intermediate panel  12  has a transposed configuration to the double-fold  11 . 4  of the slow panel  11  so that with the door  7  in the fully closed position the double-fold  11 . 4  of the slow panel  11  is at least partially accommodated within the channel  12 . 5  mounted on the intermediate panel  11 . 
         [0026]    The fast panel  13  has a different construction to the other door panels  11  and  12  primarily because, during use, larger forces are exerted on the fast panel  13 . For example, if an obstacle is present in the opening  6  during a closing operation, then any impact force would have to be transmitted through or absorbed by the leading, fast panel  13  rather than the other panels  11  and  12 . Furthermore, as explained further on in the description with respect to  FIG. 8 , the weight of the other panels  11  and  12  is partially transmitted through the fast panel  13 . The fast panel  13  is manufactured from sheet metal to provide a closed, rectangular profile having a lateral rear surface  13 . 1 , a transverse lagging surface  13 . 2 , a lateral front surface  13 . 3  and a transverse leading surface  13 . 4 . The lagging surface  13 . 2  extends forward from the front surface  13 . 3  and is folded to form a vertical channel  13 . 5 . This channel  13 . 5  has a transposed configuration to the double-fold  12 . 4  of the intermediate panel  12  so that with the door  7  in the fully closed position the double-fold  12 . 4  of the intermediate panel  12  is at least partially accommodated within the channel  13 . 5  of the fast panel  13 . 
         [0027]    As can be seen clearly from the figures, when progressing from the slow panel  11  to the intermediate panel  12  to the fast panel  13 , the depth of the panels, as defined by the transverse lagging surfaces  11 . 2 ,  12 . 2  and  13 . 2 , is sequentially reduced. The consequence of this arrangement is that in the fully opened position, as shown in  FIG. 2A , the intermediate panel  12  and the fast panel  13  are fully accommodated between the planes of the rear surface  11 . 1  and the front surface  11 . 3  of the slow panel  11 . 
         [0028]    Since the panels are manufactured from sheet metal, the provision of rear surfaces  11 . 1  and  12 . 1  on the slow and intermediate panels  11  and  12  is essential to provide sufficient mechanical strength and rigidity to the front surfaces  11 . 3  and  12 . 3  of the panels. 
         [0029]      FIG. 3  is a cross-sectional view of the telescopic landing door  7  of  FIG. 1  incorporating a synchronous linkage mechanism  50  according to the invention. A hole  16  is punched through the transverse, lagging surface  11 . 2 ,  12 . 2  and  13 . 2  of each of the panels  11 ,  12  and  13  to accommodate the linkage  50  extending from the door post  10  to the fast panel  13 . The linkage  50  is pivotally mounted to each of the panels  11 ,  12  and  13  by means of a bracket mechanism  40 . 
         [0030]    As show in greater detail in  FIG. 4 , the synchronous linkage mechanism  50  comprises a series of links L 1 , L 2 , L 3  and L 4  which extend alternatively upwards and downwards between a first pivot point P 1  mounted to the door frame  10  and a seventh pivot point P 7  mounted to the fast panel  13 . The first link L 1  extends upwards from the first pivot point P 1  and is connected at its end to the second link L 2  at pivot point P 2 . The second link L 2  extends downwards from the second pivot point P 2  and is connected at its end to the third link L 3  at the fourth pivot point P 4 . The third link L 3  extends upwards from the fourth pivot point P 4  and is connected at its end to the fourth link L 4  at the sixth pivot point P 6 . The slow panel  11  is pivotally mounted to the linkage  50  at an intermediate point P 3  on the second link L 2 . Similarly the intermediate panel  12  is pivotally mounted to the linkage  50  at an intermediate point P 5  on the third link L 3 . 
         [0031]    A second identical synchronous linkage mechanism  50 ′ is provided below the first linkage  50  and a rigid bar  52  interconnects corresponding pivot points P 4  on both linkages  50  and  50 ′. 
         [0032]    A drive lever DL is pivotally attached to the first pivot point P 1  so as to rotate concurrently with the first link L 1  about the first pivot point P 1 . As shown in  FIG. 3 , the drive lever DL extends outwards from the synchronous linkage mechanism  50 ′ and into the elevator shaft  1 . A roller R is mounted to the end of the drive lever DL. 
         [0033]    The landing door  7  is driven by a drive  60  mounted on the elevator car C. The drive  60  comprises a motor  62  to drive a closed-loop toothed belt  64  which subscribes a path between the motor  62  at one side and a return pulley  68  at the other side of the opening  6 . A vertically aligned H-beam  66  is attached to the toothed belt  64  for concurrent horizontal movement therewith. As shown in  FIG. 4 , when the elevator car is level with the closed landing door  7 , the roller R mounted to the end of the drive lever DL is accommodated in a channel defined by the H-beam  66 . As the motor  60  and toothed belt  62  move the H-beam  66  to the left, as indicated by the arrow, the drive lever DL rotates counter-clockwise concurrently with the first link L 1  about the first pivot point P 1 . This rotation of the first link L 1  causes simultaneous rotation of the remaining links L 2 , L 3  and L 4  about pivot points P 3 , P 5  and P 7  respectively and the landing door  7  opens as shown in  FIG. 5 . 
         [0034]    The skilled person will readily appreciate that a similar synchronous linkage mechanism  50  can be applied to the elevator car door in which case the roller of the drive lever of the car door linkage can be accommodated in the opposing channel of the H-beam  66  as shown in  FIG. 3 . 
         [0035]    In accordance with the provisions of the patent statutes, the present invention has been described in what is considered to represent its preferred embodiment. However, it should be noted that the invention can be practiced otherwise than as specifically illustrated and described without departing from its spirit or scope.