Abstract:
The invention relates to a conveyor for conveyor systems for conveying containers, pallets and the like, or bulk material, comprising a drum tube which extends along a longitudinal axis and has a first end and a second end opposite said first end, an electrical drive unit which is designed to exert a conveyor torque from a first axle onto the drum tube, characterised by a cartridge tube which is secured torque-resistantly and coaxially in the drum tube, and a cover which is rotatably mounted on the first axle and which covers one end of the cartridge tube, wherein the electrical drive unit is arranged inside the cartridge tube and said cartridge tube is secured coaxially inside the drum tube.

Description:
CROSS-REFERENCE TO FOREIGN PRIORITY APPLICATION 
       [0001]    The present application claims the benefit of PCT Application No. PCT/EP2015/074372 filed Oct. 21, 2015, entitled “Conveyor Device for Conveyor Installations, a Modular System, and a Method for Producing Such a Conveyor Device.” 
     
    
     FIELD OF THE INVENTION 
       [0002]    The invention relates to a conveyor, in particular a conveyor roller, for conveyor systems for conveying containers, pallets and the like, or bulk material, comprising a drum tube which extends along a longitudinal axis and has a first end and a second end opposite said first end, and an electrical drive unit which is designed to exert a conveyor torque from a first axle onto the drum tube. The invention further relates to a modular system for constructing a conveyor of a desired length and to a method for producing such a conveyor. 
       BACKGROUND OF THE INVENTION 
       [0003]    Conveyors of this type are used for different purposes in logistics applications. A conveyor according to the invention may be a drum motor, for example, or a motorised roller having a drum body. Accordingly, a drum body can also be understood to be a supporting tube or outer tube of a motorised roller or roller body. 
         [0004]    Drum motors are deployed, for example, in such a way that they are mounted in a frame by means of an axle, which is then attached stationarily in relation to the frame and torque-resistantly to the frame. The drum body rotatably mounted on an axle is driven and made to rotate by means of a drive unit inside the drum body. The drive unit is supported by the axle and is connected to the drum body on the driven side. The drum motor can be used to drive other devices, for example, a conveyor line consisting of a plurality of conveyor rollers, by means of a belt or the like. The drum motor can also be used directly as a conveyor element in a conveyor line and can carry the conveyed item and convey it by rotation of the drum body. One preferred use is to dispose the drum motor as a drive element at the end of a conveyor belt system and to drive a conveyor belt, which is partly wound around the drum body, and to make it move by rotation of the drum body. Another use consists in disposing the drum motor as a drive element in the middle of the lower run, with the conveyor belt being wound partly around and driven by the drum body. 
         [0005]    Drum motors with different driving power are known from the prior art. The driving power ranges from about 10 W to 6 KW and can transmit a torque of up to 1000 Nm via the drum body. Due to their particular construction, drum motors are characterised by the specific problem of heat being difficult to dissipate from the drive means, which is disposed inside the drum body for compact construction. For some drum motors with high power ratings, filling the drum body with oil is, therefore, an established technique in the prior art for ensuring that the drum motor remains thermally stable even under heavy loads. However, due to higher levels of efficiency, it is possible in some cases to dispense with filling the drum body with oil even when such components are used. A gearless electrical drum motor having a plurality of electrical stator windings and a shared, permanently excited rotor or an identical number of mechanically connected, permanently excited series of rotors is known from DE 20 2012 000 793 U1. The single electrical stator windings are connected electrically and mechanically in such a way that they can be connected individually or collectively in order to adjust the power of the drum motor to the load requirements. 
         [0006]    In contrast to drum motors, motorised rollers for roller drives are generally equipped with a drum body of smaller diameter, referred to here as a drum tube, and typically have a power rating of less than 100 W, typically in the range between 10 and 40 W. Such roller drives are used to carry and convey items in roller conveyor lines. Roller conveyors can be combined with a plurality of idle rollers arranged in parallel, which are driven by the motor-driven conveyor roller via a belt drive or chain drive, as the case may be. In curved roller conveyors, the rollers are arranged with their axes at an angle to each other. 
         [0007]    The drum motors and roller drives can be used, for example, to convey pallets, to convey parcels in parcel dispatch centres, to convey containers in depots of various kinds, or for transporting luggage in airports, and in numerous other applications. 
         [0008]    The invention is based on the realisation that conveyors must be produced in different lengths according to the field of application, depending, for example, on the size of the items being conveyed or on conditions on the specific premises. According to the prior art, producing conveyors of different lengths is only economical if a limited assortment of conveyors is offered in different, discrete lengths. Fulfilling individual customer wishes concerning the length of a conveyor invariably makes production more complex and expensive, in that customised sizes of conveyor rollers must be designed. This is a general problem that arises, particularly when supplying spare parts for defective rollers, or when small follow-up deliveries are made. 
       SUMMARY OF THE INVENTION 
       [0009]    The object of the present invention is, therefore, to provide and produce a conveyor of the kind initially specified, which can easily be provided with customised lengths easily and without any special manufacturing effort. 
         [0010]    This object is achieved, according to the invention, by a conveyor of the kind initially described, having a drive cartridge comprising a cartridge tube which is secured torque-resistantly and coaxially in the drum tube and a cover which is rotatably mounted on the first axle and which covers one end of the cartridge tube, the electrical drive unit being arranged inside the cartridge tube and said cartridge tube being secured coaxially inside the drum tube. 
         [0011]    The drum tube is preferably in the form of a hollow cylinder and consists of a material which allows the drum tube to be cut individually to a desired length while simultaneously having sufficient strength for the conveyor to be used in conveyor systems. Such a material may preferably consist of steel, aluminium and/or plastic (e.g. polyvinyl chloride (PVC)). An inner surface of the drum tube is preferably cylindrical in shape. 
         [0012]    The circumferential surface of the cartridge tube is preferably cylindrical and has an outer diameter which is approximately equal to the inner diameter of the drum tube. The cover covers one end of the cartridge tube, preferably sealingly, and preferably has an outer diameter which is greater than the inner diameter of the drum tube. These dimensions allow the drive cartridge to be preferably insertable through the second end of the drum tube into the drum tube until the cover abuts the second end of the drum tube like a flange. The cartridge tube and the cover may be designed as an integral unit. It is preferable that the cartridge tube and the cover are formed from two pieces. 
         [0013]    The drive unit preferably has a stator and a rotor. The drive unit is preferably arranged coaxially with the cartridge tube. The first axle is connected torque-resistantly to the stator. In the context of the present invention, the “first axle” is to be understood as an abstract axis of rotation and preferably as a cover element which is rotatably mounted about the longitudinal axis, for example by means of a rolling bearing. The rolling bearing is preferably provided in the form of a precision oiled or greased bearing conforming to DIN 625 (DIN: the German standardisation body), and is made of Niro steel, for example. It is also preferable that the axle of the cover has a through hole through which a supply line for the electrical drive unit extends. The through hole is preferably formed by a bore or recess extending longitudinally in the axle, in particular a cylindrical hole having a diameter which allows the supply line to pass through. This allows the drive unit to be supplied with electrical energy using a particularly simple and advantageous design. 
         [0014]    It is further preferred that the rotor be arranged inside the stator. The stator preferably has coil windings and is surrounded by the cartridge tube, which rotates around the stator when in operation. The torque is transmitted from the rotor to the cartridge tube and the cover by means of a gear, in particular a spur gear transmission. When asynchronous motors are used, as is preferable, the rotor has a so-called squirrel cage. However, synchronous motors are also used, in which permanent magnets are arranged in the rotors. 
         [0015]    One key advantage of the conveyor according to the invention is that it is possible to use a standardised drive cartridge to produce conveyors of different lengths. A core concept behind the invention is to use the same, prefabricated drive cartridge to produce conveyors of different lengths. Other elements required to produce the conveyor, such as the drum tube, differ partly in design. The expression “drive cartridge” is to be understood here as an element whose dimensions remain the same in different conveyors and which is inserted into drum tubes of different lengths to form the conveyor. The expression “drive insert” can also be used synonymously for “drive cartridge”. 
         [0016]    According to one preferred embodiment of the inventive conveyor, the cover extends into the cartridge tube and has an outer diameter in a flange portion outside the cartridge tube which is equal to the outer diameter of the drum tube. 
         [0017]    The cover preferably consists of two portions, namely the flange portion and an insertion portion. The flange portion sealingly covers the second end of the cartridge tube. When the conveyor is in the assembled state, the flange portion covers the second end of the drum tube. The insertion portion of the cover preferably projects into an interior of the cartridge tube and has an outer diameter which provides an interference fit for the insertion portion in the cartridge tube. The cover preferably forms one element of the prefabricated drive cartridge. 
         [0018]    At its end face, the cover may have one or more oil holes extending through the cover into the cartridge tube. The oil holes are used to feed oil into or to remove oil from the interior of the drum tube. 
         [0019]    According to another preferred embodiment of the inventive conveyor, a torque-resistant connection between the cartridge tube and the drum tube has or is formed by an interference fit between the outer diameter of the cartridge tube and the inner diameter of the drum tube. An “interference fit” (pressure fit) is preferably to be understood to mean that the outer diameter of the cartridge tube is equal to or even slightly greater than the inner diameter of the drum tube. These relative sizes are chosen in such a way that the cartridge tube can be pressed into the drum tube during production, but such that a torque-resistant connection is formed between the cartridge tube and the drum tube when the conveyor is in operation. 
         [0020]    According to a preferred development of the embodiment described above, the torque-resistant connection between the cartridge tube and the drum tube has an adhesive bond. As an alternative, the torque-resistant connection between the cartridge tube and the drum tube is formed by said adhesive bond. For example, an adhesive producing the torque-resistant connection may be provided between an outer surface of the cartridge tube and an inner surface of the drum tube. 
         [0021]    In another preferred embodiment of the inventive conveyor, the cartridge tube has an insert cover at one end, which is rotatably mounted on a second axle by means of a rolling bearing, said second axle having a recess at an end face of the cartridge tube for receiving a stub shaft. The insert cover is preferably inserted into the cartridge tube at one end that is opposite the end at which the flange portion is arranged, that is, the end face is one that faces away from the cover. The recess is preferably designed to receive the stub shaft torque-resistantly. This can be done by the stub shaft being received in the recess with a precise fit or with an interference fit. The recess is preferably in the form of a blind hole in the second axle, said blind hole being form rotationally symmetrically about the longitudinal axis. In the context of the present invention, the “second axle” is to be understood as an abstract axis of rotation and preferably as an insert cover element which is rotatably mounted about the longitudinal axis, for example, by means of a rolling bearing. The rolling bearing is preferably in the form of a precision oiled or greased bearing conforming to DIN 625, for example, of Niro steel. 
         [0022]    According to a development of the embodiment described above, the cartridge tube and the insert cover extend through the drum tube from the first to the second end of the drum tube, with the stub shaft projecting from the first end of the drum tube. To that end, the drum tube has a length which is equal to the total length of the cartridge tube and the insert cover in the axial direction. The insert cover simultaneously forms a covering for the end of the drum tube, with the stub shaft projecting from the insert cover and thus from the drum tube. This development is the shortest conveyor which can be produced in accordance with the invention. The length of the drive cartridge thus forms a lower limit for a conveyor, according to the invention, that is, the drum tube forms the outer circumferential surface of the conveyor, e.g., for conveying containers, pallets, and the like. At one end of the conveyor, the first axle projects in the direction of the longitudinal axis for mounting the conveyor in a conveyor frame. At another end of the conveyor, the stub shaft projects in the longitudinal axial direction for mounting the conveyor in a conveyor frame. In other words, the conveyor provided in accordance with this development of the invention is rotatably mounted in a conveyor frame, when in operation, at its first end by means of the stub shaft and at its second end by means of the first axle. The portions of the stub shaft and the first axle projecting from the ends of the conveyor are preferably in the form of axles with spanner flats, which have parallel lateral cuttings at the ends of the axles. These axles with spanner flats fit into matching profiles having open elongate holes. 
         [0023]    According to another preferred embodiment of the inventive conveyor, the drum tube has a drum tube cover at the first end, which is rotatably mounted on a third axle by means of a rolling bearing, wherein the third axle is designed as a bushing for the stub shaft and one end of said stub shaft projects from the drum tube cover. The drum tube cover preferably has an insertion portion and a flange portion. The insertion portion is inserted into the drum tube until the flange portion abuts the first end of the drum tube. In the context of the present invention, the “third axle” is to be understood as an abstract axis of rotation and preferably as a drum tube cover element which is rotatably mounted about the longitudinal axis, for example, by means of a rolling bearing. The rolling bearing is preferably in the form of a precision oiled or greased bearing conforming to DIN 625, for example, of Niro steel. It is also preferable that the axle has a through hole, in particular, a cylindrical hole, through which the stub shaft extends in the assembled state. The stub shaft preferably has an outer diameter in one portion, which allows it to pass with a precise fit through the through hole, thus counteracting any forces acting on the stub shaft transversely to its axial direction. It is also preferred that the stub shaft is connected torque-resistantly to the third axle. The through hole is preferably formed by a through bore or axle recess extending in the axial direction, in particular by a cylindrical hole having a diameter which matches the outer diameter of the stub shaft in that portion. 
         [0024]    According to one development of the embodiment described above, the stub shaft extends in the assembled state through the third axle and projects into the recess in the second axle to be received therein. An embodiment is thus provided specifically for medium lengths of conveyor according to the present invention. The drum tube has a length which is greater than the length of the cartridge tube. At these lengths, the stub shaft is sufficiently long to extend through the third axle in the drum tube cover and to project into the second axle in the insert cover. Due to this structure, the stub shaft is stabilised not only by the bushing in the third axle, but also by its being received preferably with a precision fit in the second axle. 
         [0025]    According to a further variant of the development of the conveyor described above, the stub shaft has a diameter in an intermediate section between the drum tube cover and the insert cover, which prevents the intermediate section from being received into the second and/or the third axle, respectively, in the assembled state. A distance spacer is thus provided between the drum tube cover and the insert cover, in that the diameter of the stub shaft bar, measured transversely to the longitudinal axis, is greater in each case than the diameter of the bushing in the third axle and/or than the diameter of the recess in the second axle. This simultaneously allows the conveyor to be easily assembled. The intermediate section can thus serve as a stop member for inserting the stub shaft into the recess of the second axle. The intermediate section can simultaneously serve as a stop member for inserting the drum tube cover into the drum tube. Preferably, the dimensions of the intermediate section in the direction of the longitudinal axis are such that said intermediate section provides a distance spacer between the cartridge tube and the drum tube cover, with which both the cartridge tube of the drive cartridge and the insertion portion of the drum tube cover can be fully inserted into the drum tube, in particular, until the cover portion of the drive cartridge abuts the second end of the drum tube and/or until the flange portion of the drum tube cover abuts the first end of the drum tube. 
         [0026]    According to an alternative development of the embodiment described above, the conveyor has an insert member which is designed to be inserted into the drum tube and which is rotatably mounted on a fourth axle, wherein the fourth axle is designed to receive the stub shaft and the stub shaft extends in the assembled state through the third axle and projects into the fourth axle. An embodiment is thus provided for relatively long conveyors. The insert member may have an outer diameter, for example, which is approximately equal to or slightly greater than the inner diameter of the drum tube (interference fit), the insert member being inserted torque-resistantly into the drum tube, for example, by an interference fit or by an adhesive bond. It is further preferred that the insert member is arranged adjacent to the drum tube cover inside the drum tube. The fourth axle preferably has a recess in the form of a blind hole or, preferably, in the form of a through hole into which the stub shaft extends. When viewed in the longitudinal axial direction from the perspective of the insert member, the stub shaft extends through the drum tube cover and projects from the drum tube cover at the first end of the drum tube. According to this development, the insert member may be spaced an arbitrary distance from the cartridge tube in the longitudinal axial direction, as long as the stability of the drum tube permits. According to this development, therefore, it is possible for relatively long conveyors to be provided. 
         [0027]    According to a further aspect of the invention, the object specified at the outset is achieved by a modular system for constructing a conveyor of a desired length, in particular, a conveyor of the kind described above, comprising
       a drum tube which can be produced with a desired length and having a first end and a second end opposite said first end,   a drive cartridge comprising a cartridge tube which is designed to be received torque-resistantly into the drum tube, and a cover which is rotatably mounted on a first axle and which covers one end of the cartridge tube, wherein a drive unit for exerting a conveyor torque from the first axle onto the drum tube is arranged coaxially inside the cartridge tube,   wherein the cartridge tube has an insert cover at one end, which is rotatably mounted on a second axle by means of a rolling bearing, wherein said second axle has a recess at the end face of the cartridge tube for torque-resistantly receiving a stub shaft, and   selectively a drum tube cover which is rotatably mounted on a third axle by means of a rolling bearing, wherein the third axle is designed as a bushing for the stub shaft, and/or   selectively an insert member which is designed to be inserted into the drum tube and is rotatably mounted on a fourth axle by means of a rolling bearing, wherein the fourth axle is designed to receive the stub shaft.       
 
         [0033]    It is further preferred that the modular system comprises a plurality of drum tubes of different lengths. The various elements of the modular system may be selectively assembled, depending on the desired conveyor length, to form a conveyor. It is still further preferred that the modular system comprises a plurality of stub shafts of varying design. For conveyors having the smallest or a medium length, in particular, the stub shaft is designed to be received in the second axle. For very long conveyors, the stub shaft is designed to be received in the fourth axle. 
         [0034]    According to a preferred embodiment of the modular system, the drum tube provided for constructing a conveyor of the smallest length has a length which is substantially equal to the length of the cartridge tube, and the stub shaft provided is one which is received in the assembled state in the recess of the second axle, wherein to construct a conveyor of medium length, at least the drum tube cover is provided, wherein the stub shaft is received in the assembled state in the recess of the second axle of the insert cover and extends through the third axle and projects from the drum tube cover, and/or wherein to construct a very long conveyor, at least the drum tube cover and the insert member are provided, wherein the stub shaft extends in the assembled state through the third axle of the drum tube cover and projects into the axle to be accommodated therein. 
         [0035]    To build a conveyor of the smallest length, the stub shaft is preferably received torque-resistantly in the recess of the second axle. To build a conveyor of medium length, it is further preferred that stub shaft is received torque-resistantly in the recess of the second axle, in the assembled state. To build a very long conveyor, the stub shaft preferably also projects into the fourth axle, in the assembled state, so as to be received torque-resistantly therein. 
         [0036]    In other words, if a conveyor having the smallest possible length is desired, a drum tube is used which is equal to the length of the cartridge tube. Such a length can also be understood as one which is slightly greater than the length of the cartridge tube, namely the total length of the cartridge tube and the flange portion of the insert cover. The stub shaft can be received by the cartridge tube and thus projects out of the drum tube. To build a conveyor whose length is greater than that of the cartridge tube, a drum tube cover is additionally required. Depending on the length of the conveyor, the stub shaft may extend through a recess in the third axle of the drum tube cover and into the second axle of the insert cover. In the case of relatively long conveyors, an additional insert member is provided which receives, with its fourth axle, and, in particular, torque-resistantly, the stub shaft, which projects through the third axle of the drum tube cover and then out of the drum tube cover. The insert member provides additional stabilisation of the stub shaft against forces acting transversely to the axial direction. 
         [0037]    According to the embodiment of the modular system as described above, the following elements are required in order to construct conveyors having customised lengths:
       a standardised drive cartridge;   three different stub shafts;   a drum tube which can be cut to a desired length;   a drum tube cover; and   an insert member.       
 
         [0043]    According to another aspect of the invention, the object specified at the outset is achieved by a method for producing a conveyor, in particular a conveyor according to any one of the preceding claims, said method comprising the steps of:
       (a) providing a drum tube which extends along a longitudinal axis and has a first end and a second end opposite said first end, wherein the drum tube is provided with a length depending on the desired length of the conveyor,   (b) providing a drive cartridge comprising a cartridge tube which is designed to be received torque-resistantly and coaxially into the drum tube, and a cover which is rotatably mounted on a first axle and which covers one end of the cartridge tube,   (c) inserting the cartridge tube into the drum tube through the second end until the cover abuts the second end of the drum tube.       
 
         [0047]    The special feature of the method according to the invention is that conveyors having customised lengths can be produced with a limited number of steps, each of which are simple and routine for those skilled in the art. A drum tube with the desired length is preferably provided by cutting a drum tube blank to a desired length. In embodiments in which the drum tube forms the outer peripheral surface of the conveyor, the length of the drum tube is substantially equal to the length of the conveyor to be produced. In the case of a conveyor with the smallest length, the length of the conveyor is substantially equal to the length of the cartridge tube plus the length of the cover portion. In the case of a conveyor of medium to very long length, the length of the conveyor is substantially equal to the length of the drum tube plus the length of the cover portion and the length of the flange portion of the drum tube cover projecting from the drum tube. 
         [0048]    According to one preferred embodiment of the method according to the invention, the method includes the further steps of:
       (d) inserting an insert cover into the cartridge tube at one end, in particular before inserting the cartridge tube into the drum tube, wherein the insert cover is rotatably mounted on a second axle by means of a rolling bearing, wherein said second axle has a recess at an end face of the cartridge tube for receiving a stub shaft, and   (e) inserting the stub axle into the recess of the second axle.       
 
         [0051]    The aforementioned steps are specifically used to produce a conveyor of the smallest length. The individual steps may be carried out in any order, or may overlap in time. Step (d) may be performed before or also after step (c), but preferably before step (c). Step (e) may be carried out before or after step (c) and/or step (d), but preferably after step d) and before step (c). The cartridge tube is preferably inserted into a drum tube having a length which is equal to the length of the cartridge tube. In this case, after the stub shaft has been inserted into the recess of the second axle and after the cartridge tube has been inserted into the drum tube, the stub shaft projects from the drum tube at the first end of the latter. The conveyor produced in accordance with this method can then be rotatably mounted in a conveyor frame by means of the stub shaft and the first axle projecting from the cover portion. 
         [0052]    According to another preferred embodiment of the method according to the invention, a drum tube cover is mounted on a third axle, the third axle being designed as a bushing for a stub shaft and the method comprising the further steps of:
       (f) inserting an insert cover into the cartridge tube at one end, in particular before inserting the cartridge tube into the drum tube, wherein the insert cover is rotatably mounted on a second axle, wherein said second axle has a recess at an end face of the cartridge tube for receiving a stub shaft,   (g) inserting the drum tube cover into the drum tube at the first end of the drum tube,   (h) guiding the stub axle through the third axle, and   (i) inserting the stub axle into the recess of the second axle.       
 
         [0057]    The aforementioned steps are specifically used to produce a conveyor of medium length. 
         [0058]    The individual steps may be carried out in any order, or may overlap in time. Steps (g), (h), and (i), in particular, may be carried out in any order. Steps (h) and (i) preferably overlap in time, meaning that one end of the stub shaft enters into the recess in the second axle and is inserted into it while the stub shaft is being passed through the third axle. It is also possible, as an alternative to the aforementioned order of steps, that the stub shaft is firstly introduced into the recess of the second axle after step (f). While the drum tube cover is being inserted into the drum tube, the stub shaft is passed simultaneously through the third axle. Regardless of the order in which the aforementioned steps (g), (h), and (i) are carried out, the stub shaft is designed in such a way that it projects in the assembled state from the drum tube cover. The conveyor thus produced can thus be mounted, by means of the stub shaft and the first axle projecting from the cover portion, on a conveyor frame for use. 
         [0059]    According to another preferred embodiment of the method according to the invention, a drum tube cover is mounted on a third axle, the third axle being designed as a bushing for a stub shaft and the method further comprising the steps of:
       (j) inserting an insert member into the drum tube, wherein the insert member is rotatably mounted on a fourth axle and the fourth axle has a recess for receiving the stub shaft,   (k) inserting the drum tube cover into the drum tube at the first end of the drum tube,   (l) guiding the stub axle through the third axle, and   (m) inserting the stub shaft into the recess of the fourth axle.       
 
         [0064]    The aforementioned steps are specifically used to produce a very long conveyor. The individual steps may be carried out in any order, or may overlap in time. Step (j) preferably follows step (c) or is carried out before step (c). Steps (k), (l), and (m) may be carried out in any order. Steps (l) and (m) may also overlap in time, meaning that one end of the stub shaft enters into the recess in fourth axle and is inserted into it while the stub shaft is being passed through the third axle. As an alternative to the aforementioned order, the stub shaft may be inserted into the recess in the fourth axle after step (j) has been performed, and after that the drum tube cover is introduced into the drum tube and the stub shaft is passed simultaneously through the third axle. The stub shaft is designed in such a way that it projects in the assembled state from the drum tube cover. 
         [0065]    As regards the advantages, embodiment variants, and embodiment details of the method according to the present disclosure and its possible further developments, reference is made to the description provided herein of the respective features, as will be understood and appreciated by those skilled in the art upon studying the following specification, claims, and appended drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0066]    Preferred embodiments of the invention shall now be described by way of example and with reference to the attached Figures, in which: 
           [0067]      FIG. 1  is a lateral cross-sectional view of an embodiment of a drive cartridge according to the invention; 
           [0068]      FIG. 2  is an end view of the drive cartridge shown in  FIG. 1 ; 
           [0069]      FIG. 3  is a perspective view of a partial cross-sectional view of the drive cartridge shown in  FIG. 1 ; 
           [0070]      FIG. 4  is a lateral partial cross-sectional view of the drive cartridge with a stub shaft as shown in  FIGS. 1-3 ; 
           [0071]      FIG. 5  is an end view of the drive cartridge shown in  FIG. 4 ; 
           [0072]      FIG. 6  is a perspective view of a partial cross-sectional view of the drive cartridge shown in  FIG. 4 ; 
           [0073]      FIG. 7  is a lateral partial cross-sectional view of a first embodiment of a conveyor according to the invention; 
           [0074]      FIG. 8  is an end view of the conveyor shown in  FIG. 7 ; 
           [0075]      FIG. 9  is a perspective view of a partial cross-sectional view of the conveyor shown in  FIG. 7 . 
           [0076]      FIG. 10  is a lateral partial cross-sectional view of a second embodiment of a conveyor according to the invention; 
           [0077]      FIG. 11  is an end view of the conveyor shown in  FIG. 10 ; and 
           [0078]      FIG. 12  is a perspective view of a partial cross-sectional view of the conveyor shown in  FIG. 10 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0079]    As referenced in the Figures, the same reference numerals may be used herein to refer to the same parameters and components or their similar modifications and alternatives. For purposes of description herein, the terms “upper,” “lower,” “right,” “left,” “rear,” “front,” “vertical,” “horizontal,” and derivatives thereof shall relate to the present disclosure as oriented in  FIG. 1 . However, it is to be understood that the present disclosure may assume various alternative orientations and step sequences, except where expressly specified to the contrary. It is also to be understood that the specific devices and processes illustrated in the attached drawings, and described in the following specification, are simply exemplary embodiments of the inventive concepts defined in the appended claims. Hence, specific dimensions and other physical characteristics relating to the embodiments disclosed herein are not to be considered as limiting, unless the claims expressly state otherwise. The drawings referenced herein are schematic and associated views thereof are not necessarily drawn to scale. 
         [0080]    The drive cartridge  100  in  FIGS. 1 to 5  is shown  6  in cross-section in  FIG. 4 , in which the sectional plane lies in line A-A shown in  FIG. 2  and in line B-B shown in  FIG. 5 , respectively. Drive cartridge  100  extends in each case along a longitudinal axis  102  between a first end  104  and a second end  106 .  FIG. 2  shows an end view of the first end  104  of drive cartridge  100 , viewed in the direction of longitudinal axis  102 . 
         [0081]    Drive cartridge  100  is mounted rotatably about longitudinal axis  102  on a first axle  108  by means of a rolling bearing  110 . First axle  108  has a through hole  112  through which a supply line  114  for supplying an electrical drive unit  116  with electrical energy extends. In operation, first axle  108  and supply line  114  are statically mounted in a conveyor system (not shown). 
         [0082]    Drive cartridge  100  has a cartridge tube  120  which has a cylindrical circumferential surface with a first diameter  122  and which extends along longitudinal axis  102 . Cartridge tube  120  extends from the first end  104  to a flange portion  124  of a cover  134 , said flange portion  124  having a second diameter  126  which is greater than the first diameter  122 . In operation, cartridge tube  120  and cover  134  of drive cartridge  100  general rotate about longitudinal axis  102 . Inside cartridge tube  120 , drive unit  116  is arranged coaxially with cartridge tube  120 . Drive unit  116  is supplied with electrical energy by means of supply line  114 . Drive unit  116  has a stator housing  115  in which a stator  118  coupled torque-resistantly to first axle  108  is arranged. The coupling between first axle  108  and stator  118  is provided by receiving first axle  108  torque-resistantly in a recess  117  of a cover  119  of stator housing  115 . Drive unit  116  also has a rotor  121 , which is enclosed by stator  118  and stator housing  115 . Rotor  121  is connected torque-resistantly to a rotor shaft  133 . Rotor shaft  133  is rotatably mounted in stator housing  115  by means of two rolling bearings  123 ,  125  and projects into a spur gear  127 . In one end portion of rotor shaft  133 , a helical gear  135  is formed which transfers a torque onto another wheel (not shown). The torque is transferred to a gear wheel  139  by means of a shaft  137 . Gear wheel  139  engages with an internally toothed gear ring  136 . Gear ring  136  is connected torque-resistantly to cartridge tube  120 . The torque of rotor  121  is transmitted in this way to cartridge tube  120 . 
         [0083]    An insertion portion  138  of cover  134  projects into cartridge tube  120  in such a way that an outer surface of insertion portion  138  is connected torque-resistantly to an inner surface of cartridge tube  120 . Cover  134  has oil holes  140 , which extend from the first end  106  of drive cartridge  100  into an interior  142  of cartridge tube  120 . 
         [0084]    An insert cover  144  having a flange portion  146  and an insertion portion  148  which projects into cartridge tube  120  is arranged in the region of the first end  104 . Gear ring  136  is securely joined to insertion portion  148  by a screw connection  147 . Insert cover  144  is mounted rotatably about longitudinal axis  102  on a second axle  108  by means of a rolling bearing  150 . A blind hole  154  forms a recess in the second axle  152 . Blind hole  154  is designed to receive a stub shaft  156  shown in  FIGS. 4 to 6 . Axle  152  is connected torque-resistantly to stator housing  115 . To that end, axle  152  projects torque-resistantly into a recess  155  in the stator housing. 
         [0085]      FIGS. 4 to 6  show the drive cartridge  100  of  FIGS. 1 to 3 , in combination with stub shaft  156 . Stub shaft  156  contains an insertion portion  158 , which is dimensioned to be received in blind hole  154 . In addition, stub shaft  156  contains a mounting section  160  which is dimensioned for torque-resistant mounting of a conveyor, produced using drive cartridge  100 , in a conveyor frame (not shown). For that purpose, portions of mounting section  160  have a cylindrical circumferential surface having flattened and planar milled recesses  162  for torque-resistant accommodation in the conveyor frame. 
         [0086]    To produce a conveyor, a drum tube (not shown) is pushed over cartridge tube  120 , or cartridge tube  120  is inserted into a drum tube. The drum tube has a length which is equal to the total length of cartridge tube  120  and flange portion  148  when insert cover  144  is inserted. Cartridge tube  120  may be inserted into the drum tube before or after stub shaft  156  is inserted into blind hole  154 . 
         [0087]      FIGS. 7 to 9  show a first embodiment of an inventive conveyor  200 . In the partial cross-sectional view shown in  FIGS. 7 and 9 , the sectional plane lies along line C-C shown in  FIG. 8 . Conveyor  200  contains the drive cartridge  100  shown in  FIGS. 1 to 3 . Identical elements are marked with the same reference signs. 
         [0088]      FIG. 7  shows a drum tube  202  which extends along a longitudinal axis  204  and has a first end  206  and a second end  208  opposite said first end  206  of drum tube  202  in the direction of longitudinal axis  204 . At its first end  206 , conveyor  200  has a drum tube cover  210  which is mounted rotatably about longitudinal axis  204  on a third axle  212  by means of a rolling bearing  214 . Drum tube cover  210  has a flange portion  216  and an insertion portion  218 . In the assembled state, insertion portion  218  projects into an inner space  220  in drum tube  202 . Flange portion  216  forms a cover for the first end  206  of drum tube  202 . Third axle  212  provides a bushing for a stub shaft  222 . Stub shaft  222  has an insertion portion  258 , which is designed to be received in blind hole  154 . For that purpose, the inner diameter of blind hole  154  matches the outer diameter of insertion portion  258 . An intermediate section  224  of stub shaft  222  has an outer diameter which is greater than the inner diameter of blind hole  154  and of the bushing in third axle  212 . In the axial direction, intermediate section  224  abuts insertion portion  258  and in the assembled state is arranged between insert cover  144  and drum tube cover  210 . A mounting section  260  of stub shaft  222  extends through the bushing of third axle  212  and has a substantially cylindrical circumferential surface in one area. In an end region of mounting section  260 , flattened, planar milled recesses  262  are provided, which are used for torque-resistant mounting of mounting section  260  in a conveyor frame (not shown). 
         [0089]    The drive cartridge  100  shown in  FIGS. 7 to 9  extends from the second end  208  of the drum tube into the inner space  220  of the drum tube. An outer surface of cartridge tube  120  contacts an inner surface of the drum tube thereby. A torque-resistant connection between cartridge tube  120  and drum tube  202  is formed by an interference fit, meaning the outer diameter of cartridge tube  120  is slightly greater than the inner diameter of drum tube  202 , such that cartridge tube  120  can be inserted into drum tube  202  with a force which is greater in amount than a maximum force acting in the direction of rotation at the transition between cartridge tube  120  and drum tube  202  when the conveyor is in operation. In this way, a torque-resistant connection is provided for operation between cartridge tube  120  and drum tube  202 . The torque-resistant connection between cartridge tube  120  and drum tube  202  is also provided by an adhesive between the outer surface of cartridge tube  120  and the inner surface of drum tube  202 . 
         [0090]      FIGS. 10 to 12  show a second embodiment of an conveyor  300  according to the invention, in particular for building very long conveyors. In the partial cross-sectional view shown in  FIGS. 10 and 12 , the die sectional plane lies along line D-D in  FIG. 11 . The drive cartridge  100  shown in  FIGS. 10 to 12  corresponds to the drive cartridge shown in  FIGS. 1 to 9 . Identical elements are marked with the same reference signs. 
         [0091]    A drum tube  302  extends along a longitudinal axis  304  and has a first end  306  and a second end  308 . A drum tube cover  310  has the same structure as the drum tube cover  210  shown in  FIGS. 7 to 9 . Identical elements are marked with the same reference signs. An insert member  312  is arranged inside drum tube  302  adjacent to drum tube cover  310 . Insert member  312  is mounted rotatably about longitudinal axis  304  on a fourth axle  314 . The fourth axle  314  has a bushing into which an insertion portion  318  of a stub shaft  320  is torque-resistantly received. Stub shaft  320  extends through the bushing in third axle  212  and projects with a mounting section  322  from drum tube cover  310 . Mounting section  322  is used for mounting conveyor  300  in a conveyor frame. The outer shape of mounting section  322  is the same as the outer shape of mounting section  160  or  260 , as shown in  FIGS. 4 to 6 and 7 to 9 , respectively. The second embodiment of a conveyor according to the invention, as shown in  FIGS. 10 to 12 , is particularly suitable for building very long conveyors. Insert member  312  serves to stabilise stub shaft  320  against forces acting transversely to longitudinal axis  304 . One importance difference in the second embodiment, compared to the first embodiment, is that the drum tube has a length with which it makes design sense to provide insert member  312 —instead of a stub shaft which extends through drum tube  210 , as shown in  FIGS. 7 to 8 , and which projects into the blind hole  154  of second axle  152 . Instead, one end of the stub shaft facing away from mounting section  322  projects into the bushing of fourth axle  314 . 
         [0092]    It will be understood by one having ordinary skill in the art that construction of the present disclosure and other components is not limited to any specific material. Other exemplary embodiments of the disclosure disclosed herein may be formed from a wide variety of materials, unless described otherwise herein. 
         [0093]    For purposes of this disclosure, the term “coupled” or “operably coupled” (in all of its forms, couple, coupling, coupled, etc.) generally means the joining of two components (electrical or mechanical) directly or indirectly to one another. Such joining may be stationary in nature or movable in nature. Such joining may be achieved with the two components (electrical or mechanical) and any additional intermediate members being integrally formed as a single unitary body with one another or with the two components. Such joining may be permanent in nature or may be removable or releasable in nature unless otherwise stated. 
         [0094]    For purposes of this disclosure, the term “connected” or “operably connected” (in all of its forms, connect, connecting, connected, etc.) generally means that one component functions with respect to another component, even if there are other components located between the first and second component, and the term “operable” defines a functional relationship between components. 
         [0095]    It is also important to note that the construction and arrangement of the elements of the present disclosure as shown in the exemplary embodiments is illustrative only. Although only a few embodiments of the present innovations have been described in detail in this disclosure, those skilled in the art who review this disclosure will readily appreciate that, unless otherwise described, many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations, etc.) without materially departing from the novel teachings and advantages of the subject matter recited. For example, elements shown as integrally formed may be constructed of multiple parts or elements shown as multiple parts may be integrally formed, the operation of the interfaces may be reversed or otherwise varied, the length or width of the structures and/or members or connector or other elements of the system may be varied, the nature or number of adjustment positions provided between the elements may be varied. It should be noted that the elements and/or assemblies of the system may be constructed from any of a wide variety of materials that provide sufficient strength or durability, in any of a wide variety of colors, textures, and combinations. Accordingly, all such modifications are intended to be included within the scope of the present innovations. Other substitutions, modifications, changes, and omissions may be made in the design, operating positions, and arrangement of the desired and other exemplary embodiments without departing from the spirit of the present innovations. 
         [0096]    It will be understood that any described processes or steps within described processes may be combined with other disclosed processes or steps to form structures within the scope of the present disclosure. The exemplary structures and processes disclosed herein are for illustrative purposes and are not to be construed as limiting. 
         [0097]    It is also to be understood that variations and modifications can be made on the aforementioned structures and methods without departing from the concepts of the present invention, and further it is to be understood that such concepts are intended to be covered by the following claims unless these claims by their language expressly state otherwise.