Abstract:
A mobile component having a roller bearing unit, in particular a mobile component having a steering roller, a roller, in particular a drive roller, being rotationally braced in a pivot unit, which is supported via a pivot bearing on the frame of the mobile component, the axes of rotation of the two pivot bearings in particular being aligned perpendicularly with respect to each other, the axis of rotation of the pivot bearing for pivoting parallel to the direction of the normal of the normal of the driving surface of the mobile component touched by the roller, a drum brake being developed on the roller, the actuation of the drum brake being able to be brought about by an electromagnet, which is connected on the frame of the mobile component, the drum brake being able to be actuated by the electromagnet via a spline gear.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to a mobile component having a roller bearing unit. 
       BACKGROUND INFORMATION 
       [0002]    It is generally known that mobile components such as shopping carts in supermarkets come equipped with steering rollers, where rollers are provided on a pivot unit and align themselves as a function of the driving direction. 
       SUMMARY 
       [0003]    Therefore, the present invention is based on the objective of further developing a mobile component, for which an electromagnetically actuable drum brake is provided. 
         [0004]    Features of the invention in the mobile component include that the mobile component is provided with a roller bearing unit, which in particular includes a steering roller, a roller, especially a drive roller, i.e., a roller of the steering roller, is rotationally braced in a pivot unit, which is supported on the frame of the mobile component via a pivot bearing, in particular the axes of rotation of the two pivot bearings being orthogonally aligned with respect to each other, the axis of rotation of the pivot bearing in particular for pivoting parallel to the direction of the normal of the driving surface of the mobile component touched by the roller, a drum brake is developed on the roller, the actuation of the drum brake is able to be induced by an electromagnet, which is connected on the frame of the mobile component, the drum brake is able to be actuated by the electromagnet via a spline gear. 
         [0005]    This has the advantage that the actuation is able to take place through the pivot bearing of the pivot unit. In other words, the electromagnet is fixed in place on the frame of the mobile component and does not have to be integrated in the pivot unit, which results in a robust construction. The spline gear, developed in the form of a bevel gear, may be used for deflecting the displacement direction of an armature part of the electromagnet induced by the electromagnet in the transverse direction. A means for deflecting the actuating force that has an especially simple design is therefore possible. 
         [0006]    In one advantageous development, a coupling, in particular a coupling that includes a ball, is situated between the electromagnet and the spline gear. This has the advantage that misalignments between the armature part of the electromagnet and the locking part used as further coupling component, i.e., the input part of the spline gear, are possible. 
         [0007]    In one advantageous development, the electromagnet has an armature part which is disposed so as to allow movement and which can be pressed against a locking part of the spline gear by a spring element, in particular when the coil of the electromagnetic is not energized, 
         [0008]    so that a further locking part of the spline gear is displaced, in particular in a direction that has a non-vanishing angle with respect to the displacement direction of the armature part, especially an angle that runs perpendicular to the displacement direction of the armature part. This is advantageous insofar as the further locking part is displaceable in the transverse direction, and a second, further locking part is displaceable counter to the transverse direction. This enables the operation of a drum brake. 
         [0009]    In one advantageous development, one of the locking parts has a sloping surface area in order to form the spline gear, and a roller, which is able to roll along the sloping surface, is braced on the other locking part, 
         [0010]    the direction of the surface normal of the sloping surface area in particular having a non-vanishing angle with respect to the displacement direction of the armature part. This is advantageous insofar as the spline gear has an especially simple design. 
         [0011]    In one advantageous development, a ball is interposed as a coupling between the armature part and the locking part, the ball in particular projecting into, or being situated within, a depression of the armature part and a depression of the locking part. This has the advantage that a simple coupling is obtainable with the aid of the ball, and the ball is always supported because the spring element of the electromagnet and the spring element disposed between the brake pad supports of the drum brake is always exerting pressure on the ball, that is to say, in particular do not release it. 
         [0012]    In one advantageous development, the coil is situated in a coil core housing part which is connected to a coil core which is at least partially surrounded by the coil, 
         [0013]    and in particular a working air gap is disposed between the armature part and the coil core, which is situated in the region covered by the coil in the longitudinal direction. That is advantageous insofar as the housing may be produced from ferromagnetic material and the magnetic field lines are therefore able to be guided directly around the coil of the electromagnet.   
         [0014]    In one advantageous development, the spline gear as the input locking part includes the locking part that is drivable by the armature part, and it has two output locking parts, each featuring a sloping surface, 
         [0015]    each output locking part being connected to a brake pad support, which is able to be pressed against a brake drum of the roller by the locking part. This has the advantage that the angular deflection enables a simple operation of the brake. 
         [0016]    In one advantageous development, the two brake pad supports are interconnected with the aid of a pivot bearing and are moved toward each other with the aid of a spring element, in particular in the circumferential direction, 
         [0017]    the pivot bearing in particular being set apart from the spring element in the circumferential direction, especially at a maximum distance. This offers the advantage that a drum brake including a restoring spring is able to be realized, which has a simple design. 
         [0018]    In one advantageous development, the roller includes a roller lining that radially surrounds the brake drum, the roller lining in particular being produced from vulcanized material, especially rubber. This is advantageous insofar as low driving noise is generated. 
         [0019]    In one advantageous development, the force that operates the drum brake is radially conducted within the pivot bearing, which advantageously results in a compact design. 
         [0020]    In one advantageous development, the pivot bearing is realized by an inner ring, which is slidingly supported inside an outer ring, their ring axes being identical, in particular, 
         [0021]    the inner ring being form-fittingly disposed inside the outer ring in the axial direction, or the outer ring inside the inner ring, 
         [0022]    the inner ring in particular being provided in a groove of the outer ring, or the outer ring being provided in a groove of the inner ring, 
         [0023]    the part having the groove, i.e., the inner ring or the outer ring, being made up of multiple parts, in particular, 
         [0024]    the outer ring in particular being fixed in place on the frame of the mobile part, and the inner ring being fixed in place on the pivoting part. This has the advantage that the pivot bearing is developed in such a way that the actuating force is able to be conducted through the radial inner region. 
         [0025]    In one advantageous development, the armature part and the locking part are spaced apart from each other in the longitudinal direction of the coil of the electromagnet, the ball of the coupling being interposed, in particular. This advantageously makes it possible to realize a simple coupling. 
         [0026]    In one advantageous development, the pivot unit is lockable on the frame in a reversible manner with the aid of a locking unit. 
         [0027]    the locking unit in particular including an electromagnet, whose linearly displaceable armature part is able to be driven into a depression, especially a bore hole, for locking, 
         [0028]    and in particular when the electromagnet is energized, the armature part is able to be driven out, counter to the force of a spring element, especially for unlocking purposes. This has the advantage that the steering roller unit is fixedly alignable in the driving direction. 
         [0029]    Further advantages are derived from the dependent claims. The present invention is not restricted to the feature combination of the claims. Those skilled in the art will discover additional meaningful possibilities for combining claims and/or individual claim features and/or features of the specification and/or of the figures, that arise from the stated objective and/or the objective resulting from a comparison with the related art, in particular. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0030]      FIG. 1  shows a cross section through a roller bearing unit of a mobile component having a drum brake according to the present invention. 
           [0031]      FIG. 2  shows a longitudinal section through the rollers of the roller bearing unit. 
           [0032]      FIG. 3  shows a control element of the drum brake. 
           [0033]      FIG. 4  shows an oblique view of the roller bearing unit. 
           [0034]      FIG. 5  shows brake pad supports  11 , which are displaceable by the control element. 
       
    
    
     DETAILED DESCRIPTION 
       [0035]    The mobile component according to the present invention is preferably implemented as a driverless transport system and/or as an automatically steered vehicle. The present invention consequently also relates to mobile transport systems. 
         [0036]    The mobile component has roller bearing units, which are mounted on the frame of the mobile component and in essence shunt the weight force to the floor. In addition, the mobile component has a drive wheel, which is pressed against the driving surface by a spring element and is drivable by an electric motor. 
         [0037]    Each roller bearing unit has rollers, which are supported via a roller bearing unit, the roller bearing unit itself being rotationally supported on the frame of the mobile component. 
         [0038]    The rollers are able to be braked with the aid of an electromagnetically actuable brake device, the brake device having a design that resembles a drum brake. 
         [0039]    When energized, a coil  31  generates a magnetic field, which reduces air gap  1  between a coil core  3  connected to a housing part  6  and an armature part  7 . 
         [0040]    Coil  31  is provided around a sleeve-type coil brace, which is made of aluminum or plastic and functions as a sliding bearing for an armature part  7 , which is is fixed so as to allow it to move in the longitudinal direction of coil  31 . 
         [0041]    When coil  31  is energized, armature part  7  is attracted in the direction of coil core  3 , counter to the spring force of a spring element which pushes armature part  7  away from coil core housing part  4 . Coil core housing part  4  surrounds coil  31  and routes the magnetic field conducted inside coil core  3  along the outside of coil  31 . Armature part  7  projects into the coil interior, so that an air gap  1  between armature part  7  and coil core  3  is greater when coil  31  is not energized than when coil  31  is energized. 
         [0042]    Armature part  7  and coil core  3  are made of ferromagnetic material, such as steel or ferrite. 
         [0043]    At its first end, spring element  5  is braced on coil core housing part  4 , and at its second end, it is supported on armature part  7 . Spring element  5  thus pushes armature part  7  out of the space region surrounded by coil  31  and the coil brace. When energized, on the other hand, armature part  7  is pulled into this space region. 
         [0044]    Housing part  6  surrounds coil core housing part  4  including spring element  5 . 
         [0045]    Housing part  6  is connected to support plate  32 . Outer ring part  28  is connected to support plate  32 . 
         [0046]    Sliding bearing element  29  is situated between outer ring part  28  and inner ring part  30 . Outer ring part  28  and inner ring part  30  thus are braced against each other in a rotatable manner, the axis of rotation being identical to the axis of symmetry, i.e., the longitudinal axis, of coil  31  and armature part  7 . 
         [0047]    The disk with a bore pattern of bores  22  is connected to inner ring part  30 , especially by screws. Bores  22  are situated at the same radial distance from the axis of rotation and are spaced apart from each other in the circumferential direction, especially at regular intervals. 
         [0048]    A locking unit, which includes a coil  25 , is also situated on support part  32 ; when coil  25  is energized, a locking latch  23  is pulled into coil  25  in the direction of coil core  26 , once again counter to the spring force of a spring element  24 , and the locking latch is thereby pulled out of bore  22  and disk  8  released as a result. When no current is supplied, on the other hand, spring element  24  presses locking latch  23  into the bore and thereby fixates the rotary position of disk  8 , i.e., the angular position of disk  8  relative to support part  32 . This makes it possible to specify the driving direction of the mobile component. 
         [0049]    Armature part  7  is in operative connection with locking part  20  by means of a coupling  21 . The coupling is realized in the form of a ball, which is situated between locking part  20  and armature part  7  and projects into a respective recess, i.e., into a recess on locking part  20  and into a recess on armature part  7 . 
         [0050]    Locking part  20  in conjunction with locking part  9  forms a spline gear. Locking part  9  has a sloping surface, so that when armature part  7  displaces locking part  20  in the direction of locking part  9 , this locking part  9  is shifted transversely to the displacement direction of locking part  20 . Bearing rollers, which roll along the sloping surface, are braced on locking part  20  in order to reduce friction. One of the two bearing rollers rolls along the sloping surface developed on locking part  9 , so that it is pushed away transversely to the displacement direction of locking part  20 . A further bearing roller  19  is similarly disposed on locking part  20 , so that another locking part  18  is shifted in the opposite direction of locking part  9  when locking part  20  is displaced in the downward direction, i.e., in the direction of its longitudinal axis. 
         [0051]    Locking part  18  is braced on support element  16  via bearing rollers  17 , and locking part  9  is supported on locking part  18  via bearing rollers  15 . 
         [0052]    A brake pad support  11 , which is provided with a brake pad  10  on its outer circumference, is situated in the end region of locking part  9  facing away from locking part  20 . 
         [0053]    When locking part  9  is pushed away by displaced locking part  20 , brake pad  10  overcomes air gap  12  and is pressed against brake drum  14 , so that braking takes place. 
         [0054]    Brake drum  14  is developed as an annular part and carries roller lining  13  on its outer periphery, which is is made of plastic, rubber or some other vulcanized material, in particular. The roller rolls along the driving surface via roller lining  13 . 
         [0055]    When locking part  18  is pushed away by shifted locking part  20 , the further brake pad support, connected to locking part  18 , and its brake pad  10  disposed thereon overcome a corresponding air gap and are pressed against brake drum  14  as well, so that braking is occurring. 
         [0056]    In other words, when locking part  20  is displaced in the downward direction, the two locking parts  9  and  18  are pushed away from each other by the spline gear. This takes place counter to the spring force generated by a spring element, which presses the two brake pad supports  11  against each other. 
         [0057]    When locking part  20  slides out, i.e., when it is displaced in the upward direction, the brake pad supports are therefore brought closer to each other. 
         [0058]    Brake pad carriers  11  are rotationally mounted at a circumferential position with the aid of a pivot bearing  50 . 
         [0059]    The spring element is situated on the opposite side of pivot bearing  50  in the circumferential direction in order to press brake pad carriers  11  towards each other. Brake pad supports  11  are connected to a locking part  9  or  18  in this circumferential angular range, so that the displacement of locking parts  9  and  18  must take place counter to the spring force generated by the spring element. 
         [0060]    Sleeve  2 , made of aluminum or plastic, in particular, forms a radially inwardly directed delimitation of coil  31 , and thus functions at least partially as a coil brace, but does not conduct a magnetic field. 
         [0061]    Coil core  3  projects into sleeve  2 , so that air gap  1  between coil core  3  and coil core housing part  4  is delimited by sleeve  2  and coil core  3  as well as by coil core housing part  4 . Coil core housing part  4  conducts the magnetic field lines arriving from coil core  3  back at the outer circumference and via an air gap, into armature part  7 , which guides the magnetic lines into the interior space surrounded by the coil, so that only working air gap  1  between coil core  3  and armature part  7  still needs to be overcome by the magnetic field lines. 
         [0062]    Spring element  5  held in place on coil core housing part  4  exerts downward pressure on armature part  7 , i.e., in the direction of the axis of symmetry of sleeve  2 . 
         [0063]    Brake drum  14  is connected to a shaft  27 , which is braced on a support element via a bearing. This support element is disposed in a manner that allows it to pivot, the pivot axis corresponding to the longitudinal axis of locking part  20 . This makes it possible for the roller to rotate in the driving direction and realizes the bracing of the roller with over-running. The pivot axis, i.e., the axis of rotation, of the pivoting motion simultaneously is also the transmission of the force that is operating the drum brake, which is induced by the magnetic force of the lift magnet and the counteracting spring force of spring element  5 . 
         [0064]    The spline gear makes it possible to deflect the actuating force routed through the pivot axis into the drum brake, which is situated outside the pivot axis because of the after-running of the rollers, i.e., pivot rollers. 
         [0065]    The ball acting as coupling  21  corrects alignment errors, especially angular deviations between armature part  7  and locking part  20 . 
         [0066]    Inner ring  30  is made up of multiple parts in order to simplify the installation of the pivot bearing. 
       LIST OF REFERENCE NUMERALS 
       [0067]      1  air gap 
         [0068]      2  sleeve, in particular made from aluminum or a plastic material 
         [0069]      3  coil core 
         [0070]      4  coil core housing part 
         [0071]      5  spring element 
         [0072]      6  housing part 
         [0073]      7  armature part 
         [0074]      8  disk with bore pattern of bore holes  22   
         [0075]      9  locking part of the spline gear 
         [0076]      10  brake pad 
         [0077]      11  brake pad support 
         [0078]      12  Working gap of the brake 
         [0079]      13  roller lining 
         [0080]      14  brake drum 
         [0081]      15  bearing roller 
         [0082]      16  supporting structure 
         [0083]      17  bearing roller 
         [0084]      18  locking part of the spline gear 
         [0085]      19  bearing roller 
         [0086]      20  locking part of the spline gear 
         [0087]      21  coupling, in particular ball 
         [0088]      22  bore 
         [0089]      23  locking latch 
         [0090]      24  spring element 
         [0091]      25  coil of the locking unit 
         [0092]      26  coil core 
         [0093]      27  shaft 
         [0094]      28  outer ring part of the pivot bearing 
         [0095]      29  sliding bearing element, especially made of plastic or a soft material such as aluminum or bronze 
         [0096]      30  inner ring of the pivot bearing 
         [0097]      31  coil of the brake 
         [0098]      32  support plate 
         [0099]      50  pivot bearing