Abstract:
An elevator has a mechanical linear drive arranged laterally at an elevator shaft head to drive at least one belt that moves a car and a counterweight in the shaft. The belt is fixed in the shaft at opposite ends and extends about a drive wheel of the elevator drive. Deflection rollers of the drive determine the angle of encirclement of the belt on the drive wheel.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     The present invention relates to an elevator consisting of an elevator car movable in an elevator shaft and a counterweight, wherein the elevator car and the counterweight are connected by way of a support means guided over redirecting rollers and wherein a drive drives the elevator car and the counterweight.  
         [0002]     An elevator installation is shown in the U.S. Pat. No. 6,138,799 in which an elevator car and a counterweight are movable in an elevator shaft along guide rails. The elevator car and the counterweight are connected by means of cables, wherein a 2:1 cable guidance with underslinging of the elevator car is provided. The cable ends are each arranged at the upper end of the elevator shaft. A mechanical linear drive is arranged on the counterweight. A stationary cogged belt is provided as a drive means and is stretched between a shaft pit and a shaft head. The cogged belt loops around a gearwheel of the mechanical linear drive, wherein the drive climbs along the stationary belt.  
         [0003]     A disadvantage of this known equipment is that high production costs arise with the separate supporting means and drive means. In addition, the elevator functions only reliably with a correctly tightened cogged belt. Moreover, the problem of energy feed to the counterweight has to be solved by drag cables.  
       SUMMARY OF THE INVENTION  
       [0004]     The present invention meets the object of avoiding the disadvantages of the known equipment and of creating a competitive elevator with a mechanical linear drive and preferably belt-shaped drive means. In that case the running direction of the drive means does not need to be changed by the linear drive itself. Only if it appears advantageous due to the space conditions in the shaft is a corresponding redirection provided in the linear drive itself.  
         [0005]     The advantages achieved by the present invention are that the linear drive can be mounted in a space-saving manner along the drive means. The shaft head is suitable particularly for different arrangement variants and driving or supporting means guide variants. The linear drive can be installed, depending on the respective power and mechanical dimensions, in the shaft head at the most suitable location, for example in a corner, without reducing the safety space. Moreover, the linear drive operates with large redirection angles and without transverse forces. 
     
    
     DESCRIPTION OF THE DRAWINGS  
       [0006]     The above as well as other advantages of the present invention will become readily apparent to those skilled in the art from the following detailed description of a preferred embodiment when considered in the light of the accompanying drawings in which:  
         [0007]      FIG. 1  is a schematic elevation view of an elevator according to the present invention with a mechanical linear drive arranged laterally adjacent the top of the elevator shaft;  
         [0008]      FIG. 2  is a schematic elevation view of an elevator according to a second embodiment of the present invention with a mechanical drive arranged at the top of the elevator shaft;  
         [0009]      FIG. 3  is a fragmentary schematic elevation view of an elevator according to a third embodiment of the present invention with a mechanical linear drive arranged laterally adjacent the top of the elevator shaft and having a transmission;  
         [0010]      FIG. 4  is a fragmentary schematic elevation view of an elevator according to a fourth embodiment of the present invention with a mechanical linear drive arranged laterally adjacent the top of the elevator shaft;  
         [0011]      FIG. 5  is a fragmentary schematic elevation view of an elevator according to a fifth embodiment of the present invention with a mechanical linear drive arranged laterally adjacent the top of the elevator shaft with a redirecting roller having brake;  
         [0012]      FIG. 6  is a fragmentary schematic elevation view of an elevator according to a sixth embodiment of the present invention with a mechanical linear drive arranged laterally adjacent the top of the elevator shaft with a drive belt;  
         [0013]      FIG. 7  is a fragmentary schematic elevation view of an elevator according to a seventh embodiment of the present invention with a mechanical linear drive arranged laterally adjacent the top of the elevator shaft with a drive belt via a redirecting roller; and  
         [0014]      FIG. 8  is a schematic elevation view of a cantilever-mounted elevator according to an eighth embodiment of the present invention with a mechanical linear drive. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0015]     An elevator denoted by  1   a  and consisting of a car  3  and a counterweight  4  movable in an elevator shaft  2  is illustrated in  FIG. 1 . The elevator  1   a  offers free space in the shaft head for over-travels. The elevator car  3  is guided by means of a first guide rail  5  and by means of a second guide rail  6 . The counterweight  4  is guided by means of a third guide rail  7  and by means of a fourth guide rail (not illustrated). The guide rails are supported in a shaft pit  8 , wherein the vertical forces are conducted into the shaft pit  8 . The guide rails  5 ,  6 ,  7  are connected by brackets (not illustrated) with the shaft wall. Buffers  9 , on which buffer plates  10  of the elevator car or the counterweight  4  can be placed, are arranged in the shaft pit  8 .  
         [0016]     At least one belt  11 , preferably a cogged belt, with a 2:1 belt guide is provided as a supporting and driving device. If a mechanical linear drive  12  laterally arranged at the second guide rail  6 , for example in the shaft head  2 . 1 , drives the belt  11  at a vertical belt portion  11 . 1  in looping manner by means of a drive wheel  13  through one unit, the elevator car  3  or the counterweight  4  moves vertically by a half unit. One end of the belt  11  is arranged at a first belt fixing point  14  and the second end of the belt  11  is arranged at the second belt fixing point  15 . The belt  11  is guided over a first redirecting roller  16 , over a profiled roller  17 , over a second redirecting roller  18 , over a third redirecting roller  19 , over the drive wheel  13  and over a fourth redirecting roller  20 . The first redirecting roller  16 , the second redirecting roller  18  and the profile roller  17  are integrated in a floor  21  of the elevator car  3 , wherein the belt runs in a floor channel  21 . 1 . The profiled roller  17  has a toothing corresponding with the toothing of the belt  11 . The first redirecting roller  16  and the second redirecting roller  18  guide the belt on the untoothed side by means of flanges arranged at the end faces. The third redirecting roller  19  arranged at the second guide rail  6  is disposed by its toothing in engagement with the toothed side of the belt  11  and has a brake for normal operation. The drive wheel  13  is disposed by its toothing in engagement with the toothed side of the belt  11 . Deflecting rollers  22  of the linear drive  12  produce the looping angle of the belt  11  at the drive wheel  13 . The drive wheel  13  can also be one of the deflecting rollers  22 . Not illustrated is or are the motor or the motors for the drive wheel  13 . The fourth redirecting roller  20  is arranged in the counterweight and is comparable in construction with the first redirecting roller  16  or with the second redirecting roller  18 .  
         [0017]     As the belt  11  there can be provided, instead of a cogged belt, a flat belt or a wedge-ribbed belt. The wedge-ribbed belt provided with longitudinal ribs has good guidance characteristics and an increased traction capability. Such flat belts contain steel or synthetic strands of approximately 0.5 millimeters to 3 millimeters. Two belts guided in parallel can also be provided, wherein in addition the redirecting rollers or the deflecting rollers or the drive wheel can be doubled. Redirecting rollers or deflecting rollers or the drive wheel can be, for example, 50 millimeters size in diameter or larger. A motor can also be present per drive wheel. The motor can be, for example, an asynchronous motor or a synchronous motor with or without permanent magnets.  
         [0018]      FIG. 2  shows an elevator  1   b  with the mechanical linear drive  12  arranged at the top in a horizontal belt run  11 . 2 . In the case of the illustrated belt guide the belt has a bend in the same sense. The linear drive  12  is connected by means of its housing  12 . 1  with the first guide rail  5  and with a cross member  23 . One of the deflecting rollers  22  serves at the same time as a redirecting roller which redirects the belt run from the vertical to the horizontal or conversely. The other end of the cross member  23  is carried by the second guide rail  6 , at which the third redirecting roller  19  together with a brake is arranged. Moreover, the two cable fixing points  14 ,  15  are arranged at the other end of the cross member  23 . The elevator car  3  can travel by its upper edge  3 . 1  at most to a height H symbolized by dashed lines.  
         [0019]      FIG. 3  shows an elevator  1   c  with a mechanical linear drive, which is arranged laterally at the top in the vertical belt run  11 . 1  and is supported on the guide rails  6 ,  7 , with a motor  24  and a transmission  25  in a housing  27   c.  The increased distance for reciprocal bending preserves the belt  11 . One of the deflecting rollers  22  serves at the same time as a redirecting roller and is provided with a brake  26 . The elevator car  3  can travel to a position directly below the linear drive  12  as shown in dashed line.  
         [0020]      FIG. 4  shows an elevator  1   d  with the mechanical linear drive  12  arranged laterally at the top in the horizontal belt run  11 . 2  and supported on the guide rails  6 ,  7 , wherein one of the deflecting rollers  22  at the same time serves as redirecting roller and is provided with a brake (not shown). A housing  27   d  of the linear drive  12  is connected with the cross member  23 . This variant offers optimum space utilization above the counterweight  4 .  
         [0021]      FIG. 5  shows an elevator  1   e  with the mechanical linear drive  12  arranged laterally at the top in the horizontal belt run  11 . 2  and supported on the guide rails  6 ,  7 , wherein one of the deflecting rollers  22  at the same time serves as a redirecting roller and is provided with a brake (not shown). A housing  27   e  of the linear drive  12  serves at the same time as a cross member. A fifth redirecting roller  28  is provided with a brake  29 . This embodiment avoids transverse forces acting on the rails and offers belt protection.  
         [0022]     In the case of the embodiments of FIGS.  1  to  5  the direction of the belt run at the outlet of the linear motor  12  changes relative to the direction of the belt run at the inlet of the linear drive  12  at most by approximately 90°, wherein the inlet or outlet of the linear drive  12  is at the deflecting rollers  22 . In the case of the embodiment according to  FIG. 1  the direction of the belt run running out is the same as the direction of the belt run running in. In the case of the embodiments according to FIGS.  2  to  5  the direction of the belt run changes from the vertical to the horizontal or conversely.  
         [0023]      FIG. 6  shows an elevator if with the mechanical linear drive  12 , which is arranged laterally at the top and supported on the guide rails  6 ,  7  with a drive belt  30  that drives the belt  11 . Functionally identical components are provided with the same reference numerals as in the case of the preceding examples of the various embodiments. The drive belt  30  is placed under the belt  11  and guided over the fifth redirecting roller  28 , which is integrated in a housing  27   f.  This embodiment is distinguished by a large amount of looping. Moreover, the drive belt  30  makes possible small bending radii and freedom of positioning for the traction pulley  13 .  
         [0024]      FIG. 7  shows an elevator  1   g  with the mechanical linear drive  12  in a housing  27   g,  which is arranged laterally at the top and supported on the guide rails  6 ,  7 , with the drive belt  30  which is guided over the fifth redirecting roller  28  and which drives the belt  11 . The fifth redirecting roller  28  is arranged above the first guide rail  5 . Functionally identical components are provided with the same reference numerals as in the case of the preceding embodiments. This embodiment enables belt guidance in a preserving manner without reciprocal bending and with a large looping angle.  
         [0025]     In the case of the embodiments of  FIGS. 6 and 7  as well, the direction of the belt run at the linear motor itself changes only by 90°. However, for optimization of the cable guidance the redirecting rollers are arranged downstream in order to adapt the belt or cable departure point to the disposition of the car.  
         [0026]     As already explained above, the redirecting rollers or the deflecting rollers or the drive wheel can have a diameter of approximately 50 millimeters. The following example shows the advantageous dimensions or the advantageous weight of the mechanical linear drive in relation to the counterweight and to the elevator car:  
         [0027]     diameter of the deflecting roller—53 millimeters  
         [0028]     diameter of the drive wheel—50 millimeters  
         [0029]     spacing of the deflecting roller from the drive wheel—60 millimeters  
         [0030]     looping angle of the belt at the drive wheel—137° 
         [0031]     dimensions of the complete linear drive with two motors (installation according to  FIG. 1 )—270 millimeters height, 150 millimeters width, 750 millimeters depth  
         [0032]     dimensions of the counterweight—1600 millimeters height, 100 millimeters width, 610 millimeters depth  
         [0033]     weight of linear drive without motor—23 kilograms  
         [0034]     weight with two motors—75 kilograms  
         [0035]     weight of counterweight—1000 kilograms  
         [0036]     weight of elevator car—630 kilograms (with 675 kilograms of useful load)  
         [0037]     The advantageous dimensions or the advantageous weight of the mechanical linear drive allows or allow an installation which is independent in terms of position even in the case of unfavorable space conditions. The characteristics of thin belts, which permit small bending radii, can thus be fully utilized.  
         [0038]     As shown in  FIG. 8 , the mechanical linear drive  12  can also be used in the case of an elevator  1   h,  for example in the case of a cantilever-mounted elevator with a 1:1 belt guide, in which one belt end is arranged at the elevator car  3  and the other belt end at the counterweight  4 . The linear drive  12  is arranged between the travel path of the elevator car  3  and the shaft wall, wherein the elevator car  3  can move past the linear drive  12 . The linear drive  12  substantially consists of the drive wheel  13 , the deflecting roller  22  and a drive (not illustrated). The function of the second deflecting roller  22  is taken over by the redirecting roller  19 , wherein a looping angle of the belt  11  at the drive wheel  13  of, for example, approximately 137° is achieved. The redirecting roller  19  can also be equipped with a brake. The linear drive  12  shown in  FIG. 8  can, for example, also be used for the elevator installation according to  FIG. 1 .  
         [0039]     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.