Abstract:
Equipment for suspension of a car or a counterweight in an elevator installation and methods for mounting and for maintenance of the suspension apparatus includes deflecting roller units. The car or the counterweight hangs at support belts that are each connected with the car or the counterweight by an associated one of the deflecting roller units. Each roller unit provides space for one of the support belts. The roller unit provides compensation for different elongations of the several support belts and it enables simple mounting of the support belts.

Description:
BACKGROUND OF THE INVENTION 
   The present invention relates to equipment for suspension of a car or a counterweight in an elevator installation and to methods for mounting and for maintenance of such suspension means. 
   German patent document DE 2333120 illustrates such an elevator installation, in which a car and a counterweight are suspended by means of looping around of steel belts. Several deflecting rollers are in that case combined into a deflecting roller unit, which is connected with the car or with the counterweight. The individual deflecting rollers are in that case arranged on a common axis so that the individual deflecting rollers are capable of different rotation. 
   However, this solution has disadvantages. The deflecting roller units have to be matched to the number of steel belts that are used and be correspondingly combined. Alignment of the deflecting roller unit to the take-off direction of the belts can take place only as a whole and an individual length compensation of the belts due to unequal load distribution, aging and wear or imprecise mounting is not possible with this deflecting roller unit. 
   SUMMARY OF THE INVENTION 
   An object of the present invention is to provide equipment that eliminates the aforesaid disadvantages. Compensation for different support belt elongation and adjustment of the deflecting rollers to special arrangements, for example of the counterweight, shall be made possible. 
   The present invention relates to equipment for the suspension of a car or counterweight in an elevator installation and to methods for mounting and for maintenance of suspension means, wherein the car or the counterweight hangs at support belts and the support belts are connected with the car or counterweight by means of several deflecting rollers. 
   According to the present invention the equipment for suspension of a car or a counterweight is constructed in such a manner that each deflecting roller is installed in an associated deflecting roller unit, each deflecting roller unit offers space for an individual support belt and each support belt is connected by the associated deflecting roller unit with the car or with the counterweight. 
   The advantage of this invention is that each deflecting roller unit is associated with one support belt. Preparation of the deflecting roller unit for a specific order is thereby possible in simple manner, since the number of deflecting roller units corresponds directly to the number of support belts. Moreover, the equipment is suitable for use in modernization of existing elevator installations. Modernization consists of parts of an existing elevator installation that are partly or entirely replaced. A typical modernization approach consists in replacing an old drive system. Old elevator installations or the drive systems thereof were often provided with direct suspension and support cables were as a rule used as support means. A new drive system preferably operates with looped suspension and with support belts. The drive system can thereby be operated with low torques and correspondingly low motor current, which enables use of more economic subassemblies. The equipment according to the present invention for suspension of car or counterweight is best suited to this purpose since it has small dimensions and is connectable in an ideal manner with existing cars or counterweights. A further advantage results from the direct usability of the deflecting roller unit for mounting the support belt in an elevator installation. This facilitates the mounting process. 
   The deflecting roller unit is, in an advantageous embodiment, individually adjustable. It can accordingly be used for compensation for length change of the support belt. The use of a tie bolt for connecting the deflecting roller unit with the car or with the counterweight enables each individual deflecting roller unit to be able to be adjusted to a required take-off direction of the support belt. By take-off direction there is understood the direction which corresponds with the resultant force line resulting from the force sum of the support belt running to and running from the deflecting roller unit. 

   
     DESCRIPTION OF THE DRAWINGS 
     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: 
       FIG. 1  is a schematic cross-sectional elevation view of an elevator installation with a suspended car and counterweight according to the present invention; 
       FIG. 2  is an enlarged perspective the suspension of the car shown in  FIG. 1 ; 
       FIG. 3  is a perspective view of one of the deflecting roller units shown in  FIG. 2 ; 
       FIG. 4  is a perspective view of an alternate embodiment of the deflecting roller unit shown in  FIG. 3  with a compensating spring according to the present invention; 
       FIG. 5  is a cross-sectional view of the deflecting roller unit according to the present invention; 
       FIG. 6  is a schematic elevation view of an example of the mounting of a support belt according to the present invention; and 
       FIG. 7  is a schematic plan view of an example of an arrangement of deflecting roller units in an elevator installation. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIG. 1  shows an arrangement, by way of example, of an elevator installation  1  with a loop-suspended car  2  and counterweight  3 . Support means  6  are in that case fastened in the region of a shaft head  8  or directly to a drive unit  4  by means of a support means end fastening  9 . The support means  6  runs in a first section to a suspension  7  of the car, which is arranged on the car  2  and is guided in a second section from the car  2  to a driving or deflecting pulley of the drive unit  4 . A third section of the support means  6  further leads from the drive unit  4  to a suspension  7  which is arranged at the counterweight  3  and from the counterweight  3  in turn to a support means end fastening  9  at the counterweight side. The support means  6  is formed by a support belt. The cross-section of the support belt  6  is flat, wherein the surface serving for traction can be smooth or shaped. As a rule at least two of the support belts  6  carry the car  2  and the counterweight  3 . The support belts  6  are arranged adjacent to one another. 
   Equipment according to the present invention for suspension of the car  2  or the counterweight  3  is illustrated in  FIG. 2 . Several support belts  6 —in the illustrated example, three support belts  6 —are arranged in the immediate vicinity of one another. Each support means  6  is in that case according to the present invention connected with the car  2  or with the counterweight  3  by means of an associated deflecting roller unit  10 . Direct vicinity means that no other parts are arranged between the support belts  6  such as serve for guidance, holding or fastening of the support means  6 , inclusive of the necessary safety spacings. The advantage of this solution is that preparation of the deflecting roller unit  10  for a specific order is possible in a simple manner. A number of deflecting roller units  10 . 1 ,  10 . 2 ,  10 . 3  to be supplied is coordinated to the number of support belts  6  which are provided. Pre-assembly of the deflecting roller devices  10  specific to order is redundant. Moreover, the individual deflecting roller units  10  are individually rotatable and/or adjustable about an axis to a required take-off direction of the respective support belt. The spacing of the deflecting roller units  10  from the car  2  or from the counterweight  3  is adjustable, for example by threaded rods  20 . Thus, the individual deflecting roller units  10  can be used for compensation for changes in length of the support belts  6 . Length changes can result during the installing, for example, by reason of different support belt lengths, or they occur in operation, for example by reason of unequal loading of the support belts  6 . The deflecting roller unit  10  according to the invention can also be used without limitation for elevator installations with a divided support belt arrangement. 
     FIG. 3 ,  FIG. 4  and  FIG. 5  illustrate an advantageous form of embodiment of the deflecting roller unit  10  in detail. The deflecting roller unit  10  comprises a deflecting roller  11 . The deflecting roller  11  is matched to a width BT of the support belt  6 . The illustrated deflecting roller unit  10  thus offers space for exactly one of the support belts  6 . This allows an optimum utilization of the space, since no unnecessary space is lost. The deflecting roller  11  is mounted on an axle  12 , advantageously by means of roller bearings  13 , and the axle  12  is connected with a U-shaped carrier  14 , which laterally retains the deflecting roller  11 . The axle  12  is in that case provided, for example at one end, with securing means  15  against turning and on the other side seals with the U-shaped carrier  14 . The sealing takes place in that the axle  12  is provided with a shoulder and a flange  16 , which is expanded to the U-shaped carrier  14 . This embodiment is particularly space-saving and accordingly enables small spacings between adjacent deflecting roller units  10 . 1 ,  10 . 2 ,  10 . 3 . 
   The support belt  6  engages the deflecting roller  11  usually with an angle of wrap of approximately 180°. A spacer  17  is arranged in the region of the deflecting roller  11  not embraced by the support belt  6 . The spacer  17  can be of one-piece or multi-piece construction. The spacer  17  determines the spacing of the U-limbs, which are formed by the U-shaped carrier  14 , at the side of the U-shaped carrier  14  which is open with respect to the U-shape and it prevents objects from dropping into the entry zone of the support belt  6 . 
   The U-shaped carrier  14  forms a semicircular curve at its end opposite the spacer  17 . This curve forms the receptacle for a cylinder  18  which has a transverse bore  19 . A tie bolt  20  extends through the transverse bore  19  and is provided at its end facing the deflecting roller  11  with a nut  21 , preferably a castle nut, and securing cotter pin  22 . The tie bolt  20  represents the connection of the deflecting roller unit  10  with the car  2  or the counterweight  3 . The deflecting roller unit  10  is adjustable about an axis AV defined by the tie bolt. The cylinder  18  arranged in the U-shaped carrier  14  forms a ball socket  25  and additionally enables adjustment of the deflecting roller unit  10  about the axis of the cylinder  18 . In the illustrated embodiment the cylinder  18  is secured by means of a securing plate  23  against lateral slipping. The securing plate  23  at the same time prevents damage of the deflecting roller  11  by the tie bolt  20 . The illustrated embodiment requires little space, can be manufactured economically and is appropriately adjustable to a take-off direction of the support belt  6 . 
   The deflecting roller  10  is constructed in such a manner that the constructional width BU required by the deflecting roller unit  10  is less than 1.7 times the width BT of the support belt  6 . The illustrated example offers space for a support belt  6  of approximately 30 millimeters width BT. The associated deflecting roller unit  10  requires a width BU of approximately 43 millimeters. A spacing of adjacent deflecting roller units  10  can be fixed at approximately 48 millimeters. Existing elevator installations with support cables usually have a support cable spacing of approximately 48 millimeters. The embodiment according to the present invention can thus be used particularly well for modernization of existing elevator installations. Existing connecting hole patterns of car and counterweight can be used. This is favorable in terms of costs, since the modernization interface is placed at an easily definable location. 
   The tie bolt  20  is secured to the end facing the deflecting roller  11  by the securing cotter pin  22 , preferably a spring clip. This enables simple mounting and demounting of the deflecting roller unit  10  in the case of need. 
   The tie bolt  20  is, at the end of the tie bolt  20  at the car side or counterweight side, selectably executed with a fixed fastening or the fastening is adjustable. A fixed fastening can be a screw head, which transmits the supporting force of the support belt  6  to the car  2  or the counterweight  3 . This fastening is advantageous when no space for more extensively adjustable fastenings is present. 
   An adjustable fastening is, as illustrated in  FIG. 3 , the tie bolt  20  with a thread, on which the threaded nut  21  with corresponding locking means and securing cotter pin is arranged, which transmits the supporting force from the support belt  6  to the car or the counterweight. Compensation for elongation of the support belt  6  is carried out in that the support belt  6  is tensioned or relaxed by means of the tie bolt  20  or by adjustment of the threaded nut  21  on the tie bolt  20 . This is advantageous, since through this adjustment compensation can be provided for a substantial elongation of the support belt  6 , as a change in length at the tie bolt  20  corresponds with twice the change in length of the support means  6 . An adjustment of the tension of the support belt  6  by means of the tie bolt  20  is thus very space-saving. 
   Advantageously at least one of the support belt end fastening  9  or the deflecting roller unit  10  is executed with a spring-loaded bias. Compensation can thereby be provided for different degrees of stretching or elongation of several support belts  6  relative to one another during operation of the elevator installation  1 . One embodiment of the fastening of the deflecting roller unit  10  proposes, as illustrated in  FIG. 4 , that a spring  24  arranged on the tie bolt  20  enables compensation for different stretching or elongation of the support belt  6 . 
   In a preferred embodiment the tie bolt  20  is additionally pivotably fastened at both ends by way of a ball socket. The fastening leads at one end of the tie bolt  20  to the car or to the counterweight and at its other end to the cylinder  18  of the deflecting roller unit  10 . This is advantageous, since the deflecting roller unit  10  can be adjusted in correspondence with a take-off direction of the support means  6  and the tie bolt  10  is thus substantially free of bending stresses. 
   The deflecting roller  11  is shaped in correspondence with a form of construction of the support belt  6 . It has a smooth deflecting surface or a structure. In the case of need it is provided with lateral shoulders. The expert defines the construction in correspondence with requirements for traction, noise or guidance accuracy. 
     FIG. 7  shows a further advantageous form of use of the equipment according to the invention. As a rule the centre axis AZ of the several deflecting rollers  11 , which are arranged on the car  2  or the counterweight  3 , are arranged on a vertical plane EK. This means that the axes  12  of several deflecting roller units  10  considered from above are arranged in a line. Considered from the side, the axes  12  can be set at different height levels, as is apparent in  FIG. 2 . In an alternative arrangement, however, the centre axes AZ of the deflecting rollers  11  are arranged on mutually parallel vertical planes EG 1 , EG 2 , EG 3 . This means that the axes  12  of several deflecting roller units  10  considered from above are arranged to be displaced in parallel relative to one another. An inclined setting region, which in a normal case is achieved by an inclined setting of the common fastening of the deflecting roller units  10 , can thereby be increased. 
   The deflecting roller unit  10  of the aforesaid kind can be used in particularly satisfactory manner for mounting suspension means in an elevator installation. A use of the deflecting roller  10  for this purpose is illustrated, by way of example, in  FIG. 6 . 
   A support belt  6 . 1  is in that case provided for mounting in the region of an uppermost shaft position, for example on the car  2 , which is premounted in this region or fixed there, or in an engine room. Advantageously one end  6 . 2  of the support belt is placed over the drive unit. 
   The end of the support belt  6 . 2  is now moved into the deflecting roller unit  10  and the end of the support means  6 . 2  is connected by means of the support belt end fastening  9  with a fixing point at the counterweight side. 
   The support belt  6  is let down in the shaft, wherein the support belt  6  is moved downwardly by means of the weight of the deflecting roller unit  10  until the deflecting roller unit  10  has reached the counterweight  3  premounted in the region of the shaft pit. 
   When the deflecting roller unit  10  has reached the associated counterweight  3  the deflecting roller unit  10  is fastened at the corresponding fastening point. The loose end of the support belt  6  is moved into the associated deflecting roller unit  10 , the deflecting roller unit  10  is fastened to the car  2  and is fastened by means of a further support belt end fastening  9  to the fixing point at the car side. The support belt  6  can in that case be shortened to the required support means length. 
   After mounting of all support belts  6  the support means tension can be set with the help of the tie bolt  20  or can be balanced between the support means  6 . 
   The illustrated method is simple to manage, since no support means ends have to be pulled up through the elevator shaft, but the support belt  6  can always be mounted from above to below. 
   If the car  2  is, as illustrated in  FIG. 6 , premounted in the vicinity of an uppermost stopping point or is fixed there within the scope of a modernization, the roof of the car  2  can be used as an excellent working platform. Mounting of auxiliary platforms is in that case redundant. 
   The expert will recognize further advantageous refinements of the outlined examples. Thus, for example, the expert uses individual side plates instead of the illustrated U-shaped carrier  14 , changes the illustrated sequence when mounting the support belts or adapts the illustrated 2:1 looping suspension to multiple looping suspension, which requires for each support belt  6  several deflecting roller units  10  at the car  2  or at the counterweight  3 . The equipment according to the present invention can obviously also be used as an individual deflecting roller unit at a desired location in the shaft. 
   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.