EP3504137A2

EP3504137A2 - Motor-driven conveying roller comprising a cooling sleeve pressed into the drum tube

Info

Publication number: EP3504137A2
Application number: EP18766191.3A
Authority: EP
Inventors: Ralf DOROK; Reinhold Weichbrodt
Original assignee: Interroll Holding AG
Current assignee: Interroll Holding AG
Priority date: 2017-09-15
Filing date: 2018-09-05
Publication date: 2019-07-03
Also published as: JP2020533252A; CN111295347A; EP4230551A2; WO2019052871A2; DE102017121486B4; CN111295347B; CA3074888C; KR102379627B1; KR20200053583A; BR112020004779A2; EP4230551A3; US20200270065A1; DE102017121486A1; WO2019052871A3; JP6999803B2; CA3074888A1; US11091321B2

Abstract

The invention relates to a motor-driven conveying roller (1) for conveying systems for conveying containers, pallets and the like, comprising a drum tube (2) having a cavity formed therein and a longitudinal axis (A), a shaft (4) running in the longitudinal axis (A) and on which the drum tube (2) is mounted by means of at least one rotary bearing (6), and an electric drive unit (14) arranged in the cavity. The invention is characterized by a cooling sleeve (30) which is fastened radially internally to the drum tube (2) and surrounds at least partially the drive unit (14) in a radial manner, so that a radial air gap (S) is formed between drive unit (14) and cooling sleeve (30). The invention further relates to a production method for such a conveying roller.

Description

Motor-driven conveyor roller with cooling sleeve pressed into the drum tube

The invention relates to a motor-driven conveyor roller for conveying systems for conveying containers, pallets and the like, comprising a drum tube having a cavity formed therein and a longitudinal axis, a shaft which extends in the longitudinal axis and on which the drum tube is mounted by means of at least one pivot bearing, and an electric drive unit disposed in the cavity. The invention further relates to a manufacturing method for producing a motor-driven conveyor roller of the type mentioned.

Motorized conveyor rollers of this type are used for different purposes in logistic applications. They can be used, for example, in pallet handling, in the conveyance of parcels in parcel delivery centers, for the transport of containers in warehouses of different types or for the transport of luggage in airports and in numerous other applications. In this case, such motor-driven conveyor rollers are regularly used in conveyor lines, which consist of several juxtaposed rollers whose upper peripheral surface is used in each case for receiving the conveyed. In these conveyor lines idler rollers are on the one hand arranged, which are without drive and are rotatably mounted only in a conveyor frame. Furthermore, driven conveying rollers are arranged in these conveyor sections, which are motor-operated and are set in rotation by an electric drive unit. These motor-driven conveyor rollers are constructed in such a way that the drive unit within the Roller is arranged itself, so that no outside of the roller body or drum tube arranged mechanical components are required to produce the rotation of the roller. The motor-driven conveyor rollers serve on the one hand to transport the conveyed directly on the outer peripheral surface of its roller body, on the other hand, by means of a transmission of rotation of the motor-driven conveyor roller on one or more idler rollers by means of a transmission element, such as a belt drive, by the motor-driven conveyor roller and the idler rollers in Rotation are offset in order to drive over the outer peripheral surface of the conveyed material. A problem with such motorized conveyor rollers is, especially with high power drive units, to provide sufficient cooling for the drive unit. Oil cooling is often not possible due to the structural conditions and not desired in use in the food processing industry. To be able to equip a dry-running motor-driven conveyor rollers with a high performance, cooling is required.

From DE 22 38 562 A, for example, an internal rotor electric motor is known which has radially inside the rotor laminations a heat pipe, which connects heat conduction surfaces between the rotor laminations and thus cools the rotor.

However, there is still the problem in use with conveyor rollers to bring the heat from the inside of the drum tube to the outside.

DE 103 24 664 A1 proposes a roller motor which has, axially adjacent to the electric motor, a heat sink which is connected via a pipe to the stator of the external rotor electric motor in order to conduct heat from the interior of the electric motor to the axially adjacent heat sink, which then transfers the heat to the drum tube emits. The disadvantage of this is on the one hand, the complex assembly and the restriction to external rotor motors and the uneven heat transfer and the uneven heating of the drum tube on the outside.

A similar solution is known from DE 10 2006 060 009 A1. In the solution proposed therein, heat-conducting elements are provided on the front side at both ends of the stator. The above-mentioned disadvantages apply here as well. From DE 10 2008 061 979 A1 of the present applicant, a drum motor with internal rotor electric motor and heat conducting body is known. The heat-conducting body is arranged axially adjacent to the electric motor. What is positive about the heat conduction body is that it has a plurality of radially widening graduations, so that the heat output to the drum tube is more uniform and a more uniform heating of the drum tube can be ensured. Nevertheless, there is still a need to be able to dissipate more heat and to achieve a more uniform and efficient cooling.

In particular, an application for generally smaller in diameter motor-driven conveyor rollers should be ensured in which the space is cramped than generally in drum motors.

Object of the present invention is therefore to provide a motor-driven conveyor roller of the type mentioned, which has an improved cooling, is easy to assemble and can achieve a uniform heat output to the drum tube. This object is achieved in a motor-driven conveyor roller of the type mentioned by a cooling sleeve, which is radially internally attached to the drum tube and the drive unit at least partially surrounds radially, so that a radial air gap between the drive unit and the cooling sleeve is formed.

On the one hand, it is thus provided that the cooling sleeve radially surrounds the drive unit, so that a larger-area transfer area is provided between the cooling sleeve and drive unit, as if the cooling sleeve were arranged axially adjacent to the drive unit. On the other hand, the cooling sleeve is not connected to the drive unit, but with the drum tube. In principle, it is conceivable to fix such a cooling sleeve radially externally to the drive unit, for example, to clamp it to the drive unit. However, there is a risk that the drive unit will be damaged and further problems may arise when the drive unit has to be maintained.

The cooling sleeve is therefore connected according to the invention with the drum tube and an air gap is formed between the drive unit and the cooling sleeve. A heat transfer between the drive unit and the cooling sleeve takes place primarily by thermal radiation and only partially by heat convection through the air in the air gap. Since the cooling sleeve radially surrounds the drive unit, an outer end attached to the drum tube is also removed. Laid felt even heat dissipation achieved because not only the portion of the drum tube can be used for heat dissipation, on which the drive unit is not arranged, but in particular also the area of the drive unit itself.

Furthermore, this assembly is greatly simplified. Changes to the drive unit are not required. It is only used a gap between the drive unit and drum tube to accommodate a cooling sleeve therein. The cooling sleeve can also be used to compensate for tolerances or to adapt the diameter of the drive unit to changing diameter of drum tubes. For example, it is conceivable that a drum tube may have an outer diameter of 50 mm, 60 mm or 80 mm. All three drum tubes can, however, be driven by the same drive unit. In the event that the drive unit is used in a 60 mm or 80 mm drum tube, a radial distance between the drive unit and the inner surface of the drum tube would be very large, so that cooling by means of heat radiation is severely limited. Here, the cooling sleeve can advantageously be used according to the invention. The cooling sleeve can be used to keep an air gap between the cooling sleeve and the drive unit constant, irrespective of a diameter of the drum tube, so that cooling of the drive unit by means of heat radiation to the cooling sleeve is largely independent of the diameter of the drum tube itself. It should be understood that in addition to drum tubes with 50, 60 and 80 mm and drum tubes with other diameters, about 55 mm, can give. This depends primarily on the desired requirements.

In a first preferred embodiment, the cooling sleeve is non-positively connected to the drum tube. Preferably, the cooling sleeve is pressed into the drum tube. As a result, the assembly is further simplified and it is possible to avoid additional mounting elements such as screws or the like. Also, the introduction of a weld to secure the cooling sleeve is not required. Furthermore, surface contact between the cooling sleeve and the inner surface of the drum tube is ensured in the case of a cooling sleeve frictionally connected to the drum tube, whereby heat transfer by means of heat conduction from the cooling sleeve to the drum tube is particularly effectively possible.

Furthermore, it is preferred that the cooling sleeve is slotted axially. The cooling sleeve preferably has an axial slot, which preferably runs parallel to the central axis. The slot can also run helically around the central axis. As a result, the assembly is further simplified. For mounting, it is possible to easily assemble the sleeve. to push them into the interior of the drum tube. Further, the cooling sleeve is able by axial slitting able to compensate for certain radial tolerances of the drum tube. Drum tubes are usually longitudinally welded tubes and have inside a weld, which extends in the axial direction. As a result, an inner diameter can vary slightly, so that it is expedient to form the cooling sleeve so that such tolerances can be compensated and yet a firm connection between the cooling sleeve and drum tube is provided. The cooling sleeve is preferably designed such that it exerts a permanent clamping force on the drum tube, so that unintentional release of the cooling sleeve is not possible. The slot does not have to be very far in the circumferential direction. It should have such a width that a slight compression of the cooling sleeve is possible, but not too large to use a heat conduction as optimal as possible. Preferably, the axial slot is continuous, that is, the cooling sleeve is completely slotted. Nevertheless, the cooling sleeve is formed as a whole in one piece, so that further elements and additional assembly steps can be largely avoided.

For further simplified assembly, it is also conceivable that the cooling sleeve has an assembly phase at an axial end face, preferably with an axial annular extension which has a smaller diameter than the outer surface of the cooling sleeve. As a result, the positioning of the cooling sleeve to the drum tube and the insertion, or pressing the cooling sleeve is further simplified in the drum tube.

Preferably, the drive unit has an electric motor and the cooling sleeve extends in the axial direction substantially completely over the electric motor. The electric motor of the drive unit is the component that significantly develops heat and whose heat has to be removed. By a sufficient cooling of the electric motor, a higher power can be achieved because a shutdown temperature of the electric motor by the improved cooling less frequently, or less quickly achieved. Especially the section of the drive unit, in which the electric motor is housed, therefore requires cooling.

The electric motor is preferably designed as an internal rotor electric motor, wherein the stator is connected to the shaft of the motor-driven conveyor roller and is supported on this. Basically, such a structure of motor-driven conveyor rollers is known.

Furthermore, it is preferred that the drive unit has a gear and the cooling sleeve extends in the axial direction substantially completely over the transmission. ever Depending on the type of transmission used, the overlap of the transmission by the cooling sleeve can be different. For example, in the case of a two-stage transmission, it is preferably provided that the cooling sleeve extends completely over the latter, wherein it is preferably provided in a three-stage transmission with a correspondingly longer housing that the cooling sleeve extends substantially completely over this, for example via the first two transmission stages. This makes it possible to provide only one cooling sleeve variant for both types of transmission so that identical parts can be used. Basically, as a cooling sleeve and a common part within a conveyor roller series can be used, which is so long that it extends completely over the transmission in the longest transmission design and axially with a shorter gear something. The transmission is usually arranged axially adjacent to the electric motor. Thus, the transmission also absorbs heat from the electric motor and even develops heat due to friction. Therefore, it is preferred that the cooling sleeve not only extends axially substantially completely over the electric motor, but also axially extends substantially completely over the transmission. The cooling sleeve may further extend axially adjacent to the electric motor and the transmission to ensure even more uniform transport of heat to the drum tube. Preferably, the cooling sleeve extends almost from an axial bearing cap to an opposite axial bearing cap, or a coupling unit, which couples the drum tube to the transmission.

Furthermore, it is preferred that the radial width of the air gap is substantially constant in the axial direction. That is, regardless of the axial position, the gap between the cooling sleeve and the drive unit is substantially constant. Usually, the drive unit has a uniform outer diameter, wherein also embodiments are known in which the drive unit has different outer diameters, for example due to a transmission, which may have a smaller outer diameter than the electric motor. For this case, it is preferred that the cooling sleeve has a radially inwardly extending shoulder, so that the air gap between the drive unit and the cooling sleeve can be kept constant. Cooling sleeve and drive unit are thus arranged substantially equidistantly along their axial coverage area.

The radial width of the air gap is preferably in a range of 0, 1 mm to 2.5 mm, preferably 0, 1 mm to 2.0 mm, more preferably 0, 1 mm to 1 mm, and is more preferably about 0.5 mm. It has been shown that too small a distance can have a negative effect on the assembly, but too great a distance leads to a worse cooling, because the heat radiation is dependent on the square of the Distance between the two elements. While a distance of 2.5 mm still provides good cooling, it has been found that a distance of about 0.5 mm is optimal. An air gap with a radial width of 0.5 mm allows good transfer of heat from the drive unit to the cooling sleeve, while at the same time simplifying installation and eliminating unusually high tolerance requirements that would increase manufacturing costs ,

According to another preferred embodiment, it is provided that a radially inner surface of the cooling sleeve has a surface roughness of Rz 50 or less, Rz 40 or less, preferably Rz 30 or less. Particularly preferred is a surface roughness of Rz 25 or less. The surface of the cooling sleeve is preferably finished. It has been found that a flat surface has a positive effect on the transfer of heat between the drive unit and the cooling sleeve. The surface should be as little as possible reflective, that is, for example, not polished. However, an uneven surface with grooves or the like is not positive for heat transfer. A sized surface with a surface roughness of Rz 25 has been found to be particularly suitable, since this can still be produced by conventional production methods, without causing high manufacturing costs, but at the same time allows good heat transfer between the drive unit and the cooling sleeve. Furthermore, it can be provided that a radially inner surface of the cooling sleeve has a surface treatment for absorbing thermal radiation.

The idea of transferring a surface treatment for absorbing thermal radiation to a radially inner surface of an element is also independently disclosed herein. In this respect, the technical idea of the surface treatment for absorption of thermal radiation can also be transferred to the drum tube and this solution is also disclosed herein. That is to say, independently disclosed herein is a motorized conveying roller for conveyor systems for conveying containers, pallets and the like, comprising: a drum tube having a cavity formed therein and a longitudinal axis, a shaft extending in the longitudinal axis and on which the drum tube is mounted by means of at least one pivot bearing, an arranged in the cavity electric drive unit, wherein a radially inner surface of the drum tube having a surface treatment for absorbing thermal radiation. In such cases, depending on the distance between the drum tube and drive unit, the cooling sleeve can be omitted. The surface treatment for absorbing thermal radiation further improves the transfer of heat by means of heat radiation from the drive unit to the cooling sleeve and / or the drum tube. It has been found that by preventing reflection, a transfer of heat from the drive unit to the cooling sleeve and / or the drum tube can be further improved, and so even more effective cooling of the drive unit is possible.

As suitable surface treatments have been found: coating with dark pigments, preferably black, preferably matt; anodizing; Browning; Copper. Also mixtures thereof are preferred. In particular, however, when anodizing and coppering it is important that as dark as possible, preferably black, oxides are used, in particular copper oxide. In particular, coating with dark pigments can be effected by means of painting, the use of matt lacquer being preferred over the use of glossy lacquer. Overall, it should be noted that the formation of the cooling sleeve and / or the inner surface of the drum tube as a black radiator is ideal, and a surface treatment or a combination of surface treatment should be chosen that comes as close as possible to this ideal.

It is also conceivable to provide both a cooling sleeve and a surface treatment for that axial portion of the inner surface of the drum tube, which is not covered by the cooling sleeve.

Furthermore, it is preferred that the cooling sleeve has a thermal conductivity of 100 W / mK or more, preferably 130 W / mK or more. Even higher thermal conductivities of, for example, 220 W / mK or even 160 W / mK are preferred. However, such materials typically cause higher manufacturing costs. A thermal conductivity of approx. 130 W / mK has proven to be optimal here.

It is also preferable that the cooling sleeve has a density of 3.5kg / dm ³ or less, preferably 3.0kg / dm ³ or less, more preferably 2.9kg / dm ³ or less. The cooling sleeve is moved according to the invention together with the drum tube and must be set in rotation. In order not to generate too large moments of inertia here, it is preferred that a light metal is used. Furthermore, light metals are also suitable for heat conduction, so that a synergy can be achieved here. Nevertheless, a solid material should be used and not a porous material to keep the thermal conductivity as high as possible. Preferably, the cooling sleeve is formed of an aluminum material, preferably an aluminum alloy. Suitable alloying elements here are in particular copper, magnesium, lead, manganese and silicon.

According to a further preferred embodiment, the motor-driven feed roller comprises a coupling unit designed to transmit torque from the drive unit to an inner peripheral surface of the drum tube, which has a coupling sleeve having a drive portion communicating with the drive unit and an outer peripheral output portion , wherein the coupling bush is only selectively frictionally connected for transmitting torque with the inner peripheral surface of the drum tube. In the prior art, also peripheral frictional connections are known and also such can be used here. However, a point frictional connection between the coupling bushing and the drum tube has the advantage that the construction is simplified. They permit higher tolerances compared to positive connections and fully frictional connections, which reduces production costs. As a result, a problem of excessive pressure due to lack of tolerances can be avoided and the production can be simplified as a whole and the conveyor roller can be produced more cheaply.

The coupling bush may for this purpose have a plurality of radial lugs, which are intended to be in contact with the inner peripheral surface of the drum tube. The lugs thus form contact points at which a punctual frictional connection between the coupling sleeve and the drum tube is produced. The lugs are preferably rounded in cross-section and / or have a slight trapezoidal shape, which forms a slight plateau at the radially outer end. The lugs preferably have an outer contour which is approximately part-cylindrical and extends in the axial direction at least partially, preferably completely, over the coupling bushing. Preferably, the radial tabs together define a diameter greater than the diameter of the inner peripheral surface of the drum tube. As a result, a particularly good frictional connection between the coupling bushing and the drum tube is achieved, since the lugs jointly define an excess and the coupling bushing is thus inserted under prestress into the drum tube. For this purpose, the noses are preferably made yielding. For example, the coupling bush is slotted axially. Preferably, the noses are also internally hollow.

The coupling unit with coupling bushing and the cooling sleeve can be mounted in one work step. It is also conceivable that the coupling unit and the cooling sleeve are integrally formed or summarized as a structural unit, as a module, to be mounted together.

In a second aspect of the invention, the above-mentioned object is achieved in a production method for a motor-driven conveyor roller according to one of the above-described preferred embodiments of a conveyor roller according to the first aspect of the invention with the steps: providing or producing a drum tube; Providing or producing a cooling sleeve; Pressing the cooling sleeve into the drum tube for securing the cooling sleeve in the drum tube; and inserting a drive unit in the cooling sleeve, so that a radial air gap between the drive unit and the cooling sleeve is formed.

It should be understood that the motorized conveyor roller according to the first aspect of the invention and the manufacturing method according to the second aspect of the invention have the same and similar sub-aspects as defined in particular in the subclaims. In this respect, for preferred embodiments, further features and their advantages to the above description of the motor-driven conveyor roller according to the first aspect of the invention fully referenced.

In a first variant of the production method, the cooling sleeve is pressed into the drum tube such that an axial slot of the cooling sleeve does not run along an axial weld seam of the drum tube. When the cooling sleeve is pressed into the drum tube, it exerts an internal pressure on the drum tube and thus a tangential force, which can adversely affect the weld seam. It has been found that a mechanical force input, whether due to the tangential force, or due to shearing by twisting the cooling sleeve in the region of the weld should be avoided if possible, and therefore the axial slot of the cooling sleeve is aligned so that the weld is covered with a flat portion of the cooling sleeve, that is, the axial slot of the cooling sleeve does not extend along an axial weld of the drum tube.

Furthermore, the manufacturing method preferably comprises the steps of: selecting a drum tube having a predetermined diameter from a plurality of drum tubes, the plurality of drum tubes having at least one drum tube each with outer diameters of 50 mm and 60 mm; and selecting a cooling sleeve from a plurality of cooling sleeves, the plurality of cooling sleeves having at least one respective cooling sleeve, which is provided for a drum tube with the outer diameter 50 mm and for a drum tube with the outer diameter 60 mm; the Selecting the cooling sleeve is performed so that after inserting the drive unit into the cooling sleeve, the air gap has a radial width in a range of 0, 1 mm to 2 mm, preferably 0, 1 mm to 1 mm, more preferably in about 0.5 mm. Preferably, the plurality of drum tubes comprises at least one 80 mm outer diameter drum tube and the plurality of cooling sleeves comprise at least one cooling sleeve provided for a 80 mm outer diameter drum tube.

As already mentioned above, the drive unit for drum tubes with 50 mm, 60 mm and 80 mm diameters can be identical. However, in order to ensure the best possible cooling of the drive unit, the cooling sleeve differs depending on the outer diameter of the drum tube. The outer diameter of the cooling sleeve must be adapted to the drum tube, while the inner diameter of the cooling sleeve can be formed substantially identical. The cooling sleeve thus acts as a tolerance compensation between the drum tube and drive unit and leads to a heat transfer from the drive unit to the drum tube. Depending on the requirement, which predetermines the diameter of the drum tube, according to this method either a drum tube with the outside diameter 50 mm, 60 mm or even 80 mm is selected, the corresponding cooling sleeve is selected to match this outside diameter and the drive unit is used.

The assembly is so much easier and the same parts can be used. Regardless of the size of the drum tube, sufficient cooling of the drive unit is provided so that the drive unit can be equipped with the same electric motor with a higher performance.

Further, the manufacturing method preferably includes the steps of: providing or manufacturing a clutch unit having a drive portion for communicating with the drive unit and an outer peripheral output portion; and pressing the coupling unit into the drum tube, wherein the coupling unit is only selectively frictionally connected for transmitting torque with the inner peripheral surface of the drum tube. Preferably, the pressing of the coupling unit and the pressing of the cooling sleeve are performed in one step. Preferably, the coupling unit comprises a coupling and a coupling bush, wherein the coupling bushing is only selectively frictionally connected to the transmission of torques to the inner peripheral surface of the drum tube.

Embodiments of the invention will now be described below with reference to the drawing. This is not necessarily to scale the embodiments. Rather, the drawing, where appropriate for explanation, executed in a schematized and / or slightly distorted form. With regard to additions to the teachings directly recognizable from the drawing reference is made to the relevant prior art. It should be noted that various modifications and changes may be made in the form and detail of an embodiment without departing from the general idea of the invention. The disclosed in the description, in the drawing and in the claims features of the invention may be essential both individually and in any combination for the development of the invention. In addition, all combinations of at least two of the features disclosed in the description, the drawing and / or the claims fall within the scope of the invention. The general idea of the invention is not limited to the exact form or detail of the preferred embodiments shown and described below, or limited to an object that would be limited in comparison with the subject matter claimed in the claims. In the case of specified design ranges, values within the specified limits should also be disclosed as limit values and be arbitrarily usable and claimable. For simplicity, the same reference numerals are used below for identical or similar parts or parts with identical or similar function.

Further advantages, features and details of the invention will become apparent from the following description of the preferred embodiments and from the drawings; these show in:

1 shows a full section through a motor-driven conveyor roller according to a first embodiment.

2 shows a full section through a motor-driven conveyor roller according to a second embodiment;

Fig. 3 is a side view of a cooling sleeve;

Fig. 4 frontal view of the cooling sleeve of Fig. 3;

5 shows a front view of a cooling sleeve with a surface-treated inner surface; and FIG. 6 shows a perspective view of a coupling unit with a coupling bushing. A motor-driven conveyor roller 1 has a drum tube 2, which has a central axis A. The drum tube 2 is rotatable about the central axis A. For this purpose, the conveyor roller has a shaft 4, which extends with reference to FIG. 1 right out of the drum tube 2 and can be mounted in a frame for a conveyor system. On the left with respect to Figure 1 side of the drum tube 2, no shaft is shown; the conveyor role is here rather partially broken. In normal operation, a further shaft would be provided on the left side with reference to FIG. 1, which has been omitted in the representation shown in FIG. 1 for the sake of clarity.

On the shaft 4, a pivot bearing 6 is arranged, which carries a cover 8 which is pressed into the right with respect to FIG. 1 end of the drum tube 2.

The shaft 4 has a central bore 10 through which a supply cable 12 extends. The supply cable 12 runs to a drive unit 14. The drive unit 14 has an electric motor 16 and a gear 18, which is designed here as a gear cartridge. On the output side 20 of the transmission 18, a coupling unit 22 is provided, which will be described later with reference to FIG. 6 in more detail. This coupling unit 22 serves to transmit the torque delivered by the electric motor 16 via a frictional connection 24 to the drum tube 2 in order to set the drum tube 2 in rotation.

The drive unit 14 has a housing 26 which is substantially rotationally symmetrical. The housing 26 has a diameter D1, which may be 40 mm, for example. An inner diameter D2 of the drum tube is, for example, 48 mm when the drum tube has an outer diameter of 50 mm. It should be understood that these values are only exemplary and other values are possible and preferred. The exact values depend, in particular, on the type of drive unit 14 and wall thicknesses of the drum tube 2 and the outer diameter of the drum tube 2.

In order to effect a cooling of the drive unit 14, a cooling sleeve 30 is provided according to the invention, which surrounds the drive unit 14 at least partially radially and is secured to the drum tube 2. The cooling sleeve 30 is more precisely pressed into the drum tube 2 and lies flat against the inner peripheral surface 32 of the drum tube 2. In the axial direction, the cooling sleeve 30 extends according to this embodiment (Fig. 1) from the lid 8, or just before the cover 8 to at least a portion of the transmission 18 and so radially encloses all elements of the conveyor roller 1, which emit heat. The drive unit 14 is non-rotatingly connected to the shaft 4 and is supported against the shaft 4. The housing 26 of the drive unit 14 also does not rotate. In order to enable a rotation of the drum tube 2 together with the cooling sleeve 30, an air gap S is provided between the drive unit 14 and the cooling sleeve 30. In this exemplary embodiment (FIG. 1), the air gap S has a radial width S1 in the region of the housing 26 and a radial width S2 in the region of the gear 18, which is not covered by the housing 26. The inner surface 34 of the cooling sleeve 30 is flat and has no heels or the like. Therefore, the radial width S2 in the region of the transmission 18 is slightly larger than the radial width S1 in the region of the housing 26. While the radial width S1 is approximately 0.5 mm, the radial width S2 is approximately 2 mm.

Fig. 2 shows a second embodiment of the motor-driven conveying roller 1. The same and similar elements are designated in this second embodiment with the same reference numerals as in the first embodiment (Fig. 1), so that reference is made fully to the above description of the first embodiment. In the following, in particular the differences to the first embodiment are highlighted.

In contrast to the first exemplary embodiment, the drive unit 14 has only two gear stages, with the result that the cooling sleeve 30 extends completely axially via the electric motor 16 and the gear 18. Furthermore, the cooling sleeve 30 has a portion 36 which is separated by a shoulder 38. The section 36 has a slightly reduced inner diameter, so that the cooling sleeve 30 is adapted in this section 36 to the reduced outer diameter D3 of the transmission 18. In this way, the air gap S is uniform and the radial width S1 is provided both in the region of the housing 26 and in the region of the transmission 18. A widening of the air gap S as in the first embodiment (FIG. 1) is in this embodiment (FIG. 2) not provided.

The cooling sleeve 30 itself is shown in detail with reference to FIGS. 3 to 5. The cooling sleeve 30 shown in FIG. 3 is the cooling sleeve 30 of the first exemplary embodiment (FIG. 1). The cooling sleeve 30 has a substantially cylindrical shape and is made of one piece, for example by means of (CNC) turning, (CNC) milling, extruded profiles or / or rolls, in particular cold rolls. The cooling sleeve 30 has an outer diameter D4, which is slightly larger than the inner diameter D2 of the drum tube 2, to allow a press fit. In order to allow the mounting of the cooling sleeve 30, this is axially slotted and has a slot 42. The slot has a width G, which may for example be in the range of 4 mm. The width G is dependent on the wall thickness W of the cooling sleeve 30 and the difference between the outer diameter D4 and the inner diameter D2 and also the material of the cooling sleeve 30. The width G of the slot 42 should be such that a joining of the cooling sleeve 30 in the Inside the drum tube 2 is possible even under consideration of maximum tolerances.

To further simplify the assembly, the cooling sleeve 30 on both sides mounting bevels 44, 44a, each of which opens into a shoulder 46, 46a with a diameter D5. The diameter D5 is smaller than the diameter D4, for example about 4-6% smaller. The diameter D5 should be sized so that it is also slightly smaller than the diameter D2, so that the cooling sleeve 30 can be easily inserted without difficulty and without applying a large force with the shoulder 46 into the interior of the drum tube 2 during assembly before a radial compression of the cooling sleeve 30 takes place in order to then spend this completely in the interior of the drum tube 2.

The inclination of the chamfer 44 may be, for example, in the range of 60 ° to the central axis A.

By virtue of the chamfers 44, 44a present on both sides, the cooling sleeve can be pressed in in each of the two conceivable orientations, so that incorrect assembly is ruled out and an alignment step of the cooling sleeve in order to press a defined side of the cooling sleeve forward can be omitted in an automated assembly.

Both the inner surface 34 and the outer surface 40 of the cooling sleeve 30 have a surface roughness of preferably Rz 30 or less, preferably Rz 25 or less. That is, both surfaces 34, 40 are preferably finished. The outer surface 40 should be formed so that the most secure non-positive connection with the inner peripheral surface 32 of the drum tube 2 is achieved and at the same time the largest possible contact to allow heat conduction from the cooling sleeve 30 to the drum tube 2.

The inner surface 34 should be formed so that it does not reflect, but allows the most efficient thermal radiation from the drive unit 14 to the cooling sleeve 30.

For this purpose, it may be provided that the cooling sleeve 30 on the inner surface 34 has a surface treatment 48, for example, a burnishing, a Anodization or a colored layer, in particular with a dark color, in particular black, in order to absorb heat radiation as well as possible and to reflect little heat radiation.

Overall, the cooling sleeve 30 is preferably formed from a light metal. Particularly useful here is aluminum. In this case, aluminum should be used which has a density of preferably 3 kg / dm ³ or less and has a thermal conductivity of preferably 130 W / mK or more. For this purpose, suitable alloying metals can be added to the aluminum.

Fig. 6 now shows a part of the coupling unit 22, which has already been shown in Figures 1 and 2 in section. The coupling unit 22 acts exclusively non-positively and is preferably mounted together with the cooling sleeve 30. This coupling unit 22 is described in German patent application DE 10 2016 124 689 by the present applicant, the disclosure content of which is fully incorporated herein by reference.

The coupling unit 22 has a coupling socket 50, in whose central opening 74 a toothed shaft piece 51 can engage. The toothed shaft 51 is connected to the output of the transmission 18.

The coupling bush 50 is formed in two parts and has a radially inner part 62 and a radially outer part 60. The radially outer part 60 forms an output section 52 which is frictionally connected to the inner circumferential surface 32 of the drum tube 2.

The inner part 62 has a substantially cylindrical peripheral surface 92, on which the outer part 60 is applied in the form of a corrugated sheet metal strip. The corrugated sheet metal strip of the outer part 60 forms a plurality of lugs 54, which are hollow in this embodiment and define a cavity 94 inside. As a result, the elasticity of the lugs 54 is provided, and manufacturing tolerances can be compensated.

The inner part 62 has projections 78 in which axial recesses 82 are provided. These axial recesses 82 serve on the one hand for weight reduction on the other hand to make the projections 78 elastic in order to allow a torque transmission from the toothed shaft piece 51 elastically to the inner part 62. The corrugated sheet metal strip forming the outer portion 60 cooperates both frictionally with the inner circumferential surface 32 and with the outer surface 92 of the inner portion 62. The flexibility of the metal strip tolerances can be compensated and a permanent positive connection is provided. It is conceivable that the coupling bushing 50 is inserted by means of the cooling sleeve 30 into the interior of the drum tube 2. As a result, another mounting tool for mounting the coupling bushing 50 can be saved because the coupling bushing 50 is mounted in one step with the cooling sleeve 30.

Claims

claims

A motor-driven conveyor roller (1) for conveyor systems for conveying containers, pallets and the like, comprising

a drum tube (2) having a cavity formed therein and a longitudinal axis (A),

a shaft (4) which extends in the longitudinal axis (A) and on which the drum tube (2) by means of at least one pivot bearing (6) is mounted, and

an electric drive unit (14) arranged in the cavity,

characterized by a cooling sleeve (30) which is radially internally attached to the drum tube (2) and the drive unit (14) at least partially surrounds radially, so that a radial air gap (S) formed between the drive unit (14) and the cooling sleeve (30) is.

2. Motor-driven conveyor roller according to claim 1, wherein the cooling sleeve (30) is non-positively connected to the drum tube (2).

3. A motorized conveyor roller according to claim 1 or 2, wherein the cooling sleeve (30) is axially slotted.

4. Motor-driven conveyor roller according to one of the preceding claims, wherein the drive unit (14) has an electric motor (16) and the cooling sleeve (30) extends in the axial direction substantially completely over the electric motor (16).

5. Motor-driven conveyor roller according to one of the preceding claims, wherein the drive unit (14) has a transmission (18) and the cooling sleeve (30) extends in the axial direction substantially completely over the transmission (18).

6. Motor-driven conveyor roller according to one of the preceding claims, wherein the radial width (S1, S2) of the air gap (S) in the axial direction is substantially constant.

A motor-driven conveying roller according to any one of the preceding claims, wherein the air gap (S) has a radial width (S1, S2) in a range of 0.1 mm to 2.5 mm, preferably 0.1 mm to 1 mm, particularly preferred is about 0.5 mm.

A motor-driven conveyor roller according to any one of the preceding claims, wherein a radially inner surface (34) of the cooling sleeve (30) has a surface roughness of Rz 50 or less, Rz 40 or less, preferably Rz 30 or less.

A motorized conveyor roller according to any one of the preceding claims, wherein a radially inner surface (34) of the cooling sleeve (30) has a surface treatment for absorbing thermal radiation.

10. A motorized conveyor roller according to claim 9, wherein the surface treatment comprises at least one of the following: coating with dark pigments, preferably black, preferably matt; anodizing; Browning; Copper.

1 1. A motor-driven conveyor roller according to one of the preceding claims, wherein the cooling sleeve (30) has a thermal conductivity of 100 W / mK or more, preferably 130 W / mK or more.

A motorized conveyor roller according to any one of the preceding claims, wherein the cooling sleeve (30) is one made of a material having a density of 3.5kg / dm ³ or less, preferably 3.0kg / dm ³ or less, more preferably 2.9kg / dm ³ or less is formed.

13. A motorized conveyor roller according to any one of the preceding claims, wherein the cooling sleeve (30) is formed of an aluminum material.

14. A motorized conveyor roller according to any one of the preceding claims, further comprising

a clutch unit (22) designed to transmit torque from the drive unit (14) to an inner peripheral surface (32) of the drum tube (2), which has a coupling bushing (50) which connects a drive section to the drive unit stands, and has an outer peripheral output section,

wherein the coupling bush (50) is only selectively frictionally connected for transmitting torque with the inner peripheral surface (32) of the drum tube (2).

15. A method of manufacturing a motorized conveyor roller (1) according to any one of the preceding claims, comprising the steps of:

- providing or producing a drum tube (2); - providing or producing a cooling sleeve (30);

- Pressing the cooling sleeve (30) in the drum tube (2) for securing the cooling sleeve (30) in the drum tube (2); and

- Inserting a drive unit (14) in the cooling sleeve (30), so that a radial air gap (S) between the drive unit (14) and the cooling sleeve (30) is formed.

16. The manufacturing method according to claim 15, wherein the cooling sleeve (30) is pressed into the drum tube (2) such that an axial slot of the cooling sleeve (30) does not run along an axial weld of the drum tube (2).

17. A manufacturing method according to claim 15 or 16, comprising:

- Selecting a drum tube (2) having a predetermined diameter of a plurality of drum tubes (2), wherein the plurality of drum tubes (2) has at least one respective drum tube (2) with the outer diameters 50mm and 60mm; and - selecting a cooling sleeve (30) from a plurality of cooling sleeves (30), the plurality of cooling sleeves (30) each having at least one cooling sleeve (30) provided for a barrel tube (2) having outer diameters 50mm and 60mm;

wherein selecting the cooling sleeve (30) is carried out so that after inserting the drive unit (14) into the cooling sleeve (30), the air gap (S) has a radial width (S1, S2) in a range of 0.1 mm to 2 , 5 mm, preferably 0, 1 mm to 1 mm, more preferably in about 0.5 mm.

18. A manufacturing method according to any one of claims 15 to 18, comprising the steps of:

Providing or manufacturing a clutch unit (22) having a drive portion for communicating with the drive unit and an outer peripheral output portion; and

- Pressing the coupling unit (22) in the drum tube (2), wherein the coupling unit (22) is only selectively frictionally connected for transmitting torque with the inner circumferential surface (32) of the drum tube (2).

19. A manufacturing method according to claim 18, wherein the pressing of the coupling unit (22) and the pressing of the cooling sleeve (30) take place in one step.