Abstract:
A drive drum is disclosed for a belt conveyor that gearlessly drives a conveyed product. For example, at least one motor is located inside the drum shell, said motor being fixed to the drum shell by means of a motor frame on the shell and to a fixed drum shaft by means of a fixed motor frame on said shaft; the drum shell is sealed on both sides by a base on the end face, said bases being provided with centric bearings that support the fixed drum shaft; the two ends of the fixed drum shaft are mounted on shaft fixings; at least one electric connection line, which extends inside or along the drum shaft, runs between a winding of the motor that is fixed to the fixed motor frame, on the shaft and an electric energy supply; the motor(s) has or have a cooling device for the winding; and a coolant supply and a coolant drain of the cooling device and/or a coolant connection line extend inside or along the drum shaft.

Description:
RELATED APPLICATIONS 
   This application claims priority under 35 U.S.C. §119 to German Application 10 2006 005 158.0 filed in Germany on Feb. 4, 2006, and as a continuation application under 35 U.S.C. §120 to PCT/EP2007/000543 filed as an International Application on Jan. 23, 2007 designating the U.S., the entire contents of which are hereby incorporated by reference in their entireties. 

   TECHNICAL FIELD 
   The disclosure relates to a drive drum of a belt and to a construction kit system for forming a drive drum. Belt conveyors are used industrially in the transportation of bulk goods, for example for conveying ores, coal and earth. 
   BACKGROUND INFORMATION 
   DE 41 34 050 C2 has disclosed a drive drum for belt conveyors with a motor and a gear mechanism positioned within the drum, the drive drum having, on both sides, fixed hollow shaft sections which protrude into the drum for removably accommodating the motor and gear mechanism mounted within the drum. The bearings are arranged between the hollow shaft sections, which have different lengths, and the drum. The motor and the gear mechanism are fastened in the longer hollow shaft section which has been provided at the one end with a supporting element. The proposed configuration makes it possible to quickly replace the motor and the gear mechanism without relieving the drum of tensile forces of the belt and without draining away any oil. 
   SUMMARY 
   A drive drum of a belt conveyor is disclosed which can be produced inexpensively for different power requirements. For example, a drive drum for a belt conveyor is disclosed for gearlessly driving a conveyor belt, at least one motor being arranged within the drum casing, which motor is fastened on the drum casing via a casing-side motor frame and is fastened on a fixed drum spindle via a fixed spindle-side motor frame, the drum casing being sealed at both ends by means of an end-side base, the bases being provided with centrally arranged bearings which are used for accommodating the fixed drum spindle, the two ends of the fixed base spindle being fitted using spindle fastenings, at least one electrical connecting line, which is routed within or on the drum spindle, runs between a winding, which is fastened on the fixed spindle-side motor frame, of the motor and an electrical power supply, and the at least one motor having a cooling apparatus for the winding, wherein a coolant feedline and a coolant discharge line of the cooling apparatus and/or a coolant connecting line are routed within or on the drum spindle. 
   In another aspect, a drive drum arrangement for gearlessly driving a conveyor belt is disclosed. The arrangement comprises: a drum casing, the drum casing being sealed at both ends using an end-side base, the bases being provided with centrally arranged bearings which are used for accommodating a fixed drum spindle; at least one motor being arranged within the drum casing, which motor is fastened on the drum casing via a casing-side motor frame and is fastened on the fixed drum spindle via a fixed spindle-side motor frame, the two ends of the fixed base spindle being fitted using spindle fastenings; an electrical power supply; at least one electrical connecting line, which is routed within or on the drum spindle, runs between a winding, which is fastened on the fixed spindle-side motor frame, of the motor and the electrical power supply, and a cooling apparatus for the winding, wherein a coolant feedline and a coolant discharge line of the cooling apparatus and/or a coolant connecting line are routed within or on the drum spindle. 
   A construction kit system for forming a drive drum is disclosed comprising drum casings of different lengths and/or different diameters, drum spindles of different lengths and/or different diameters, motors of different diameters and/or with different cooling systems, the motors being designed to be sufficiently narrow for at least two such motors to be capable of being inserted into the drum next to one another, wherein the drive drum can be assembled from these standard modules in an application-specific manner with respect to the required performance in terms of the required torque, the required rotation speed, the predetermined width of the conveyor belt and the desired manner of cooling. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The disclosure will be explained below with reference to the exemplary embodiments illustrated in the drawings, in which: 
       FIG. 1  shows a first exemplary embodiment of a drive drum of a belt conveyor in longitudinal section, 
       FIG. 2  shows a cross section through a drive drum of the first exemplary embodiment, 
       FIG. 3  shows a second exemplary embodiment of a drive drum of a belt conveyor in longitudinal section, 
       FIG. 4  shows a third exemplary embodiment of a drive drum of a belt conveyor in longitudinal section, 
       FIG. 5  shows a fourth exemplary embodiment of a drive drum of a belt conveyor in longitudinal section, 
       FIG. 6  shows a fifth exemplary embodiment of a drive drum of a belt conveyor in longitudinal section, 
       FIG. 7  shows a sixth exemplary embodiment of a drive drum of a belt conveyor in longitudinal section, 
       FIG. 8  shows an exemplary option for the electrical connection and the coolant connection of a winding, 
       FIG. 9  shows a seventh exemplary embodiment of a drive drum of a belt conveyor in longitudinal section, 
       FIG. 10  shows a cross section through a drive drum of the seventh exemplary embodiment, 
       FIG. 11  shows a first possible schematic of the electrical connection technology and the coolant connection technology of the seventh exemplary embodiment, 
       FIGS. 12 ,  13  show a second possible schematic of the electrical connection technology and the coolant connection technology of the seventh exemplary embodiment. 
   

   DETAILED DESCRIPTION 
   The gearless drive proposed for belt conveyors can have a very robust design and can be manufactured inexpensively in different power classes. For example, depending on the power of the drive drum required, a different number of in each case identically designed motors can be used in one and the same drum casing. 
     FIG. 1  illustrates a first exemplary embodiment of a drive drum of a belt conveyor in longitudinal section. The drive drum  1  has a hollow-cylindrical drum casing  2 , which is coated with a drum covering  3  (for example a vulcanized-on rubber layer). A conveyor belt  18  is driven by the drive drum  1 . The two end-side bases  4  and  6  of the drive drum  1  are provided with centrically arranged bearings  5  and  7 , respectively, which are used for fitting a fixed drum spindle  8 . The two ends of the drum spindle  8  which protrude beyond the bases  4 ,  6  are fitted in spindle fastenings  9 ,  10 . 
   For example, six motors A are arranged within the hollow-cylindrical drum casing  2 . The motors A can be synchronous motors with excitation using permanent magnets and with a cooling apparatus. No component parts which require feedlines for the supply of power or for cooling purposes are arranged on rotating parts. Each motor A
         is fastened on the drum spindle  8  via a spindle-side motor frame  11 ,   is fastened on the drum casing  2  via a casing-side motor frame  12 ,   has a winding  13 , which is fastened on the spindle-side motor frame  11 ,   has permanent magnets  14 , which are fastened on the casing-side motor frame  12 , as motor components for field generation,   has an air gap  15  between the permanent magnets  14  and the winding  13 ,   has a winding connection  27  for supplying power,   has a winding coolant feedline  28  and a winding coolant discharge line  29 .       

   The winding connections  27  are connected to at least one connecting line  16  for the supply of power (cable). This at least one connecting line  16  can run, for example, within the drum spindle  8 . In order to be able to operate the motors at a variable rotation speed, a converter  19 , e.g., a frequency converter, is provided which is connected on the input side to a power supply (mains)  20  and on the output side supplies the at least one connecting line  16 . 
   The winding coolant feedlines  28  are connected to a coolant feedline  25 , which is routed, for example, within the drum spindle  8 . In the same way, the winding coolant discharge lines  29  are connected to a coolant discharge line  26 , which is routed, for example, within the drum spindle  8 . Depending on the type of coolant, the coolant feedline  25  and the coolant discharge line  26  may be connected to further components. When using a liquid (for example water or oil) as the coolant, a recooler and a coolant pump for coolant transport act as further components. When using a gas (for example air) as the coolant, a fan for coolant transport is used as the further component. 
   The abovementioned fastening of the motors between the spindle-side motor frame  11  and the drum spindle  8  and between the casing-side motor frame  12  and the drum  2  can take place via technologically customary form-fitting connections, for example feather keys or toothed formations, lateral stops being used to prevent lateral sliding of the motors. It is important here that the casing of the drum  2  is sufficiently stable in terms of the high tensile force of the belt occurring and the high belt weight (tangential forces), i.e. for the resulting bending to be in the desired tolerance range. 
     FIG. 2  illustrates a cross section through a drive drum  1  of the first exemplary embodiment, the drive spindle  8  being in the form of a hollow spindle. The at least one connecting line  16  for supplying power, the coolant feedline  25  and the coolant discharge line  26  run within the hollow drum spindle  8 . The motor is formed by the spindle-side motor frame  11 , the winding  13 , the permanent magnets  14  and the casing-side motor frame  12 , it being possible to identify the air gap  15  between the winding  13  and the permanent magnets  14 . The electrical winding connection  27 , the winding coolant feedline  28 , which is connected to the coolant feedline  25 , and the winding coolant discharge line  29 , which is connected to the coolant discharge line  26 , are shown in sketched form; the same for the drum casing  2  with the drum covering  3  and the driven conveyor belt  18  which is slung around the drive drum. For the guidance of the coolant, for example, a pipeline  40 , which is connected to the coolant feedline  25  and the coolant discharge line  26 , is laid within the winding  13  of a motor A. 
     FIG. 3  illustrates a second exemplary embodiment of a drive drum of a belt conveyor in longitudinal section. In this second exemplary embodiment there is a reduced power requirement in comparison with the first exemplary embodiment. This exemplary embodiment differs from the first exemplary embodiment shown in  FIGS. 1 and 2  in that six motors B without a cooling apparatus have been inserted in a drive drum  21 . Accordingly, there is no need for the coolant feedline  25 , the coolant discharge line  26 , the winding coolant feedlines  28 , the winding coolant discharge lines  29  and the pipelines  40 . 
     FIG. 4  illustrates a third exemplary embodiment of a drive drum of a belt conveyor in longitudinal section. In this third exemplary embodiment there is a reduced power requirement in comparison with the second exemplary embodiment. This exemplary embodiment differs from the second exemplary embodiment shown in  FIG. 3  in that only three motors B without a cooling apparatus have been inserted in a drive drum  22 . The arrangement of the motors B within the drum  2  can take place in symmetrical fashion at the edges and in the center of the drum. 
     FIG. 5  illustrates a fourth exemplary embodiment of a drive drum of the belt conveyor in longitudinal section. In this fourth exemplary embodiment, there is a reduced power requirement in comparison with the third exemplary embodiment. This exemplary embodiment differs from the third exemplary embodiment shown in  FIG. 3  in that only one motor B without a cooling apparatus has been inserted in a drive drum  22 . The arrangement of the motor B within the drum casing  2  can take place in symmetrical fashion in the center of the drum. 
     FIG. 6  illustrates a fifth exemplary embodiment of a drive drum of a belt conveyor in longitudinal section. In this fifth exemplary embodiment, a shorter drive drum  24  with a shorter drum casing  17  and a shorter drum spindle  23  is used in comparison with the first four exemplary embodiments. Four motors A with a cooling apparatus are used in the drive drum  24 . 
     FIG. 7  illustrates a sixth exemplary embodiment of a drive drum of a belt conveyor in longitudinal section. In this sixth exemplary embodiment, a drive drum  30  with a drum casing  31  with an enlarged diameter is used in comparison with the first five exemplary embodiments, into which four motors C with a correspondingly enlarged diameter are inserted, which motors each have a spindle-side motor frame  35 , a casing-side motor frame  36 , a winding  37  and permanent magnet  38 . The air gap  39  is shown. The figures show motors with a cooling apparatus, but it is of course also possible for these to be motors without a cooling apparatus. The drum casing  31  is sealed at both ends by end-side bases  33 ,  34  and is provided with a drum covering  32 . The length of the drum casing  31  is equal to the length of the drum casing  17  in accordance with the fifth exemplary embodiment, with the result that the drum spindle  23  which is also used in the fifth exemplary embodiment can be used. 
     FIG. 8  illustrates an exemplary possibility for the electrical connection and the coolant connection of a winding as a schematic detailed sketch. The figure merely shows, by way of example, a motor arranged within the drive drum  1  (with the drum casing  2 , the drum covering  3 , the drum spindle  8 ) with the spindle-side motor frame  11 , the casing-side motor frame  12 , the winding  13 , the permanent magnets  14 , the air gap  15 . The lines to/from the motors can be laid into the interspaces between the motors:
         winding connection  27  between winding  13  and connecting line  16 ,   winding coolant feedline  28  between winding  13  and coolant feedline  25 ,   winding coolant discharge line  28  between winding  13  and coolant discharge line  26 .       
   This displacement of the lines into the interspaces between the motors can result in a simplified construction and simplified assembly. 
   As is apparent from the explanations above, a “drive drum construction kit system” comprising different modules, such as standard drums of different lengths and different diameters, standard drum spindles of different lengths and/or diameters and standard motors of different diameters and with different cooling systems is formed which can be assembled in a corresponding manner for the specific application case. Since no special components need to be manufactured for a specific application case but standard components (modules) which can be produced in relatively high numbers can be used, the total production costs per drive drum and belt conveyor are reduced. The selection of the components is made in an application-specific manner taking into consideration the required power, the required torque, the required rotation speed, the predetermined width of the conveyor belt and the desired type of cooling (gas as coolant, liquid as coolant, without gas/liquid cooling). Even if only a single drum casing and a single drum spindle are used as the basis, a “drive drum construction kit system” results since a broad power spectrum can be covered depending on the number of motors used in this drum casing. 
   The use of a plurality of motors instead of a single motor results in the following:
         the same motor can be used for different lengths of the drums (only the number of motors used is changed), which results in cost advantages,   the air gap can be kept constant more easily over the entire length of the drum than the air gap of a single motor with a long length,   the installation of a plurality of small motors into the drum is simpler than the installation of a single motor having a long length,   standardization of the components is possible in a simple manner.       

   In addition to the above comments it should be mentioned that it is never necessary for the fixed components, such as the drum spindle  8 ,  23  and the spindle-side motor frame  11 , for example, to have a cylindrical shape. The “first” component which absolutely must have a round cross section is the surface of the rotor of the motor on the air-gap side and the bearings  5 ,  7 . 
   Furthermore, it is never necessary for the at least one connecting line  16  and/or the coolant feedline  25 /coolant discharge line  26  to run within the drum spindle  8 ,  23 . As an alternative to this, these lines can also be routed in another way in or on the drum spindle  8 ,  23 , for example in grooves, which can simplify assembly and disassembly of the motors. 
   In this regard,  FIGS. 9 to 13  illustrate a seventh exemplary embodiment of a drive drum of a belt conveyor in longitudinal section and cross section. In contrast to the first exemplary embodiment shown in  FIG. 1 , the drum spindle  8  is designed to be solid and has a plurality of longitudinal grooves  42  which are accessible from the casing surface and in which the (electrical) winding connections  27  or  27   a - 27   f  and/or electrical connecting lines  47 , the winding coolant feedlines  28  or  28   a - 28   f  and the winding coolant discharge lines  29  or  29   a - 29   f  for the windings  13   a - 13   f  and/or coolant connecting lines  47  are routed. As has already been mentioned in connection with  FIG. 8 , the lines directly to/from the motors are laid in each case into the interspaces between the motors A or between the motor A and the end-side base/bearing. 
     FIG. 11  shows a first possible schematic of the electrical connection technology and the coolant connection technology for the seventh exemplary embodiment. In order to avoid any branch-off points in connection with the coolant feed and discharge within the drive drum  41 , a coolant distributer  43  and a coolant accumulator  44  are provided outside the drive drum  41  and connected to a recooler  45 . The following coolant cycle for the exemplary embodiment shown in  FIG. 9  results: recooler  45 —coolant feedline  25  (outside the drive drum)—coolant distributor  43 —six separate (parallel) winding coolant feedlines  28   a  to  28   f  to the six windings  13   a  to  13   f  (within the drive drum)—coolant lines within these windings—six separate (parallel) winding coolant discharge lines  29   a  to  29   f  (within the drive drum)—coolant accumulator  44 —coolant discharge line  26  (outside the drive drum)—recooler  45 . 
   Furthermore, any branch-off points in connection with the electrical connections within the drive drum  41  are avoided. The converter  19 , which is connected on the input side to the power supply  20 , is connected to the individual windings  13   a  to  13   f  via separate winding connections  27   a  to  27   f . The winding connections  27   a  to  27   f  in this case run within the grooves  42 , as do the winding coolant feedlines  28   a  to  28   f  and the winding coolant discharge lines  29   a - 29   f.    
   The further exemplary embodiment corresponds to the first exemplary embodiment. In the exemplary embodiment shown in  FIG. 10 , four symmetrically arranged grooves  42  which are each accessible from the casing surface are shown. Of course it is also possible for more than or fewer than four grooves to be provided. It is alternatively possible to guide
         only the winding connections  27  and/or the electrical connecting lines  47  (see  FIGS. 12 and 13 ) or   only the coolant feedlines  28  or   only the coolant discharge lines  29  or   coolant feedlines  28  and coolant discharge lines  29  or   only coolant connecting lines  46  (see  FIGS. 12 and 13 ) or   coolant feedlines  28  and coolant discharge line  29  or coolant connecting lines  46  and winding connections  27  or electrical connecting lines  47 
 
in one groove  42 .
       

     FIGS. 12 and 13  show a second possible schematic of the electrical connection technology and the coolant connection technology for the seventh exemplary embodiment. While a strictly parallel circuit of coolant lines and also electrical lines to the individual windings is realized in  FIG. 11 , in  FIG. 12  a series circuit of the coolant lines is used. A coolant connecting line  46  and an electrical connecting line  47  are provided in each case between two windings, these lines running in grooves  42 . 
     FIG. 12  shows two possible cooling cycle variants. In the first variant shown in the upper region of the drawing there is the following coolant cycle: recooler  45 —coolant feedline  25  (can likewise run in a groove  42 )—winding  13   f —coolant connecting line  46 —winding  13   e —coolant connecting line  46 —winding  13   d —coolant connecting line  46 —winding  13   c —coolant connecting line  46 —winding  13   b —coolant connecting line  46 —winding  13   a —coolant discharge line  26 —recooler  45   
   In the second variant shown in the lower region of the drawing the following coolant cycle results: recooler  45 —coolant feedline  25 —winding  13   a —coolant connecting line  46 —winding  13   b —coolant connecting line  46 —winding  13   c —coolant connecting line  46 —winding  13   d —coolant connecting line  46 —winding  13   e —coolant connecting line  46 —winding  13   f —coolant connecting line  46 —winding  13   e —coolant connecting line  46 —winding  13   d —coolant connecting line  46 —winding  13   c —coolant connecting line  46 —winding  13   b —coolant connecting line  46 —winding  13   a —coolant discharge line  26 —recooler  45 . 
   It will be appreciated by those skilled in the art that the present invention can be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The presently disclosed embodiments are therefore considered in all respects to be illustrative and not restricted. The scope of the invention is indicated by the appended claims rather than the foregoing description and all changes that come within the meaning and range and equivalence thereof are intended to be embraced therein. 
   LIST OF REFERENCE SYMBOLS 
   
       
         1  drive drum of a belt conveyor 
         2  drum casing 
         3  drum covering 
         4  end-side base 
         5  bearing 
         6  end-side base 
         7  bearing 
         8  drum spindle 
         9  spindle fastening 
         10  spindle fastening 
         11  spindle-side motor frame 
         12  casing-side motor frame 
         13   13   a - 13   f  winding 
         14  permanent magnets 
         15  air gap 
         16  connecting line 
         17  drum casing 
         18  conveyor belt 
         19  converter 
         20  power supply 
         21  drive drum 
         22  drive drum 
         23  drum spindle 
         24  drive drum 
         25  coolant feedline 
         26  coolant discharge line 
         27   27   a - 27   f  winding connection 
         28   28   a - 28   f  winding coolant feedline 
         29   29   a - 29   f  winding coolant discharge line 
         30  drive drum 
         31  drum casing 
         32  drum covering 
         33  end-side base 
         34  end-side base 
         35  spindle-side motor frame 
         36  casing-side motor frame 
         37  winding 
         38  permanent magnets 
         39  air gap 
         40  pipeline 
         41  drive drum 
         42  grooves 
         43  coolant distributer 
         44  coolant accumulator 
         45  recooler 
         46  coolant connecting line 
         47  electrical connecting line 
       A motor (synchronous motor with excitation using permanent magnets) with cooling apparatus 
       B motor (synchronous motor with excitation using permanent magnets) without cooling apparatus 
       C motor (synchronous motor with excitation using permanent magnets) with cooling apparatus