Abstract:
A vacuum cleaning tool for a vacuum cleaning device has a housing having a vacuum connector connected to the vacuum cleaning device. The housing has an underside and an elongate intake opening arranged in the underside. A brush roll is arranged in the housing parallel to the elongate intake opening. A drive is arranged in the housing and drivingly coupled to the brush roll. An exchangeable vacuum shoe is detachably connected to the housing and has two wall portions extending at least approximately parallel to the brush roll. The brush roll is arranged between the two wall portions.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The invention relates to a vacuum cleaning tool for a vacuum cleaning device, in particular, for cleaning floors. The vacuum cleaning tool comprises a housing having a vacuum connector for the vacuum cleaning device and an elongate intake opening provided at the underside of the housing wherein a brush roll is provided which extends parallel to the intake opening and is coupled with a drive.  
           [0003]    2. Description of the Related Art  
           [0004]    Vacuum cleaning tools are used primarily for cleaning floors. They are provided with rotating brush rolls for removing dirt from the floor. The brush rolls are arranged in the area of the intake opening. The bristle arrangement of such brush rolls is employed, depending on the type of floor, i.e., smooth floors or carpeting, with an action of different strength, wherein the bristles for a soft floor penetrate deeper than for a hard, smooth floor. As a function of the number of bristles as well as their elasticity as well as the rotational speed of the corresponding roll, a polishing effect can also be achieved which, however, is very limited as a result of the minimum weight of such universal vacuum cleaning tools. For this reason, special polishing devices have been proposed which are required in addition to a vacuum cleaning tool and have an electrical drive with considerable weight acting on a disc with a polishing bristle arrangement rotating about a vertical axis.  
         SUMMARY OF THE INVENTION  
         [0005]    It is an object of the present invention to provide a vacuum cleaning tool of the aforementioned kind which can be universally used for different types of flooring and which can be manipulated easily.  
           [0006]    In accordance with the present invention, this is achieved in that a vacuum shoe is exchangeably connected to the housing and comprises at least two wall portions extending substantially parallel to the brush roll between which the brush roll is received.  
           [0007]    By providing a vacuum shoe that is exchangeable, the operator can adapt in a simple way the vacuum cleaning tool to the respective requirements of the floor to be treated so that the respective type of flooring can be cleaned and cared for in the proper way. Accordingly, for the different types of requirements only a single device is needed which can be easily manipulated.  
           [0008]    According to a further embodiment of the invention, the vacuum shoe is provided at the ends of the wall portions with sidewalls which provide the spacing of the wall portions relative to one another. The vacuum shoe forms thus a frame which is exchangeable in its entirety. Preferably, the sidewalls and wall portions of the vacuum shoe form a monolithic body and are comprised, in particular, of a plastic material. In order to facilitate the exchange of the vacuum shoe, a clamping connection, clip connection or snap connection is provided for attachment of the vacuum shoe to the housing. In this context, it is expedient for the vacuum shoe to have openings to be engaged by projections on the housing. These openings are expediently arranged in the sidewalls of the vacuum shoe, and the projections are in the form of pins projecting laterally from the housing. In order for the pins to be able to provide a double function, i.e., on the one hand, attachment of the vacuum shoe, and, on the other hand, providing a bearing action for the brush roll, the pins are arranged coaxially to the rotational axis of the brush roll. It may be expedient to provide the openings in the form of bores in elastically deformable sidewalls of the vacuum shoe so that the introduction of the pins in the bores as well as the detachment therefrom can be realized by temporary deformation of the sidewalls. As an alternative, the openings for receiving the pins can be of a substantially circular shape and can have connected thereto a radial slot extending away from the opening wherein the end of the slot adjacent or connected to the opening has a width that is smaller than the diameter of the pin.  
           [0009]    In order for the vacuum cleaning tool not to scrape on the floor to be treated and to facilitate movement of the vacuum cleaning tool across the floor, rollers are provided at the underside of the vacuum shoe with which the vacuum cleaning tool is supported on the floor. For the treatment of carpets and soft floors, the vacuum shoe is expediently of a flat configuration so that the bristles of the brush roll project through the air intake opening.  
           [0010]    For treating hard floors, a polishing roll is provided in a vacuum shoe of a different design. It extends parallel to the intake opening and substantially fills out the intake opening. The polishing roll with its mantle surface projects past the plane of the underside of the vacuum shoe. The drive of the polishing roll is realized preferably such that the bristles of the rotating brush roll of the vacuum cleaning tool engage the surface of the polishing roll and thus cause rotation of the polishing roll. As an alternative to this, the polishing roll can have an intermediate gear for driving the polishing roll which preferably cooperates with a gear wheel provided at an end face of the polishing roll. For enabling a simple removal of the polishing roll, for example, for the purpose of cleaning the polishing roll, the polishing roll is received in bearings that can be locked or secured within the sidewalls of the vacuum shoe.  
           [0011]    As a drive for the brush roll and the polishing roll an air turbine is preferably provided which is arranged in a turbine chamber. It is also possible to provide an electric motor as a drive for the rolls instead of the air turbine. The shaft of the air turbine, or of the electric motor, is expediently provided with a toothed disc, and the shaft is coupled by means of a toothed belt with the brush roll.  
           [0012]    The polishing roll is comprised preferably of a core with axle pins at the end faces and with a cover arranged on the core and formed preferably of a textile material. In this connection, it is possible to design the cover such that it forms a uniform covering over the entire axial length and is connected to the core only in the vicinity of the axial ends of the core. The textile cover is loose (unattached) relative to the roll-shaped core across the axial length of the core between the connecting locations of the cover and the core so that as a result of the circumferential speed and the resulting centrifugal forces the cover is forced into the uneven portions and cracks of the hard flooring.  
           [0013]    The cover can also be comprised of several portions sequentially arranged in the axial direction wherein the textile covering in the respective portions has different heights and/or different degrees of hardness. For example, the portions with a higher (taller), soft covering can have a length of approximately 3 mm and the portions with a lower (shorter), hard covering can have a length of approximately 10 mm. Since the polishing roll as a result of its weight or the weight of the vacuum cleaning tool rests with the portions of the harder textile covering on the hard flooring, the fluffy textile covering of the soft portions is forced outwardly upon rotation of the polishing roll by the resulting centrifugal forces so that this covering reaches the uneven portions of the hard floor and thus produces a cleaning effect thereat. The cover of the polishing roll can be attached on the core by adhesives or by welding.  
           [0014]    According to a further embodiment of the invention, the polishing roll is supported in a floating fashion in the sidewalls of the vacuum shoe by means of elastic components. This provides an automatic adaptation of the drive of the polishing roll.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWING  
       [0015]    In the drawing:  
         [0016]    [0016]FIG. 1 is a perspective view of the exterior of a vacuum cleaning tool of a first embodiment of the vacuum shoe;  
         [0017]    [0017]FIG. 2 is a perspective illustration of the inner configuration of the vacuum cleaning tool according to FIG. 1;  
         [0018]    [0018]FIG. 3 is a representation of the vacuum cleaning tool with a vacuum shoe of a different embodiment;  
         [0019]    [0019]FIG. 4 is a view of the vacuum cleaning tool from below;  
         [0020]    [0020]FIG. 5 is a representation of the vacuum cleaning tool according to FIG. 2 with a vacuum shoe of a different embodiment;  
         [0021]    [0021]FIG. 6 is a cross-sectional view of the illustration according to FIG. 5;  
         [0022]    [0022]FIG. 7 is a longitudinal section of a first embodiment of the polishing roll;  
         [0023]    [0023]FIG. 8 is an end face view of a second embodiment of the polishing roll;  
         [0024]    [0024]FIG. 9 is a longitudinal section of the polishing roll according to FIG. 8;  
         [0025]    [0025]FIG. 10 is a perspective illustration of the vacuum cleaning tool showing also a vertical section along the axis of the polishing roll;  
         [0026]    [0026]FIG. 11 is a view in the direction of arrow XI in FIG. 10;  
         [0027]    [0027]FIG. 12 is an enlarged representation of an axial section of a bearing of the polishing roll of FIG. 11;  
         [0028]    [0028]FIG. 13 is an exploded view of the polishing roll; and  
         [0029]    [0029]FIG. 14 is an illustration of the drive with gear wheels.  
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0030]    [0030]FIG. 1 shows a vacuum cleaning tool  1  with a housing  2  on which a vacuum connector  3  for a vacuum cleaning device, not illustrated in the drawing, is arranged. In the front area of the housing  2 , a vacuum shoe  4  is arranged at its underside wherein in FIG. 1 a sidewall  5  of the vacuum shoe can be seen. The vacuum shoe  4  is provided at the underside with rollers  6  by which the vacuum cleaning tool  1  is supported on the floor to be treated. The sidewall  5  is provided with an opening  7  which is substantially circular in shape so that it is suitable for receiving a pin  8  provided laterally on the housing  2 . Since the vacuum shoe  4  should be detachable and removable in a simple way, a slot  9  extending radially relative to the opening  7  is provided wherein the end of the radial slot  9  facing the opening  7  has a width that is smaller than the diameter of the pin  8 . Accordingly, an undercut results which secures the pin  8  in the opening  7 ; an elastic widening is achieved only by applying a corresponding pressure onto the pin  8  in the direction of the slot  9 , and, in this way, the pin  8  can be moved out of the opening  7 . The introduction of the pin  8  into the opening  7  is also simple because the outer end of the radial slot  9  has a width matching that of the pin  8  so that the pin  8  can be introduced without problems and the radial slot  9  gradually tapers toward the opening  7  so that the pin  8  can snap into the opening  7 .  
         [0031]    In FIG. 2, a perspective illustration of the inner configuration of a vacuum cleaning tool  1  is illustrated. FIG. 2 shows that in the front area of the housing  2  a brush roll  10  is arranged which extends with its longitudinal axis along the air intake opening provided at the underside of the vacuum shoe  4 . The brush roll  10  is provided with a bristle arrangement which is formed of a plurality of bristles  11 . The rows of these bristles  11  are arranged in a spiral about the brush roll  10 . For driving the brush roll  10 , an air turbine  12  is provided which is arranged in a turbine chamber  13 . The turbine shaft  14  of the air turbine  12  has an end that is provided with a toothed belt wheel  15  about which a toothed belt  16  is guided for driving the brush roll  10 .  
         [0032]    The sidewalls  5  of the vacuum shoe  4  are provided with an opening  7 , respectively, and a radial slot  9  so that each opening  7  is engaged by a pin  8  arranged at the sides of the housing  2 , respectively. These pins  8  are arranged coaxially to the rotational axis of the brush roll  10  so that the pins  8  which are hollow act as bearings for the axes of the brush roll  10 . The vacuum shoe  4  comprises two parallel extending wall portions  17 ,  18  between which the brush roll  10  is arranged. On the underside of the vacuum shoe  4  the intake opening  20  is provided via which the air is taken in. The intake air enters the turbine chamber  13  via the inflow opening  19  provided between the wall portions  18  and thus drives the air turbine  12 . From the air turbine chamber  13  the air is then guided through the vacuum connector  3  to the vacuum device, not illustrated.  
         [0033]    [0033]FIG. 3 shows in a perspective illustration the vacuum cleaning tool  1  having a vacuum shoe  24  fastened on the housing  2 . The vacuum shoe  24  has a greater height in comparison to the afore described vacuum shoe  4  as can be seen when comparing the FIGS. 1 and 3. The vacuum shoe  24  is provided with rollers  26  and has sidewalls  25  in which openings  27  are provided for fastening the vacuum shoe  24  on the already mentioned pins  8 .  
         [0034]    [0034]FIG. 4 shows a view of the underside of the vacuum cleaning tool  1  with a vacuum shoe  24  fastened to the housing  2 . The vacuum shoe has four rollers  26 . The vacuum shoe  24  has an intake opening  23  and a polishing roll  30  extending parallel thereto and supported between the sidewalls  25  of the vacuum shoe  24 . The polishing roll  30  is provided with bearings  31  at its end faces for rotatably supporting it in the vacuum shoe  24 . Moreover, at the underside of the housing  2  an actuator element  22  is provided that covers in the position illustrated in FIG. 4 a bypass opening which can be opened by pivoting the actuator element  22 .  
         [0035]    [0035]FIG. 5 shows an illustration of the vacuum cleaning tool  1  according to FIG. 2 but provided with the vacuum shoe  24  of FIG. 3. As illustrated in FIG. 5, the brush roll  10  with its drive via the air turbine  12  and the toothed belt  16  is completely identical to the embodiment of FIG. 2 so that with respect to this embodiment reference is being had to the description of FIG. 2. The reference numerals in FIG. 5 are therefore identical for parts identical with those of FIG. 2.  
         [0036]    [0036]FIG. 6 shows a cross-section of the illustration according to FIG. 5, showing that the brush roll  10  is arranged between parallel extending wall portions  28  and  29 . These parallel wall portions  28 ,  29  extend in the upper area of the vacuum shoe  24 , while the polishing roll  30  is arranged in the lower area. The polishing roll  30  has an outer circumference which is of such a size that the polishing roll projects by a certain amount past the plane E of the underside of the vacuum shoe  24  in order to treat the flooring. As is illustrated in FIG. 6, the bristle length of the bristles  11  of the brush roll  10  is large enough for engaging the surface of the polishing roll  30  so that, when driving the brush roll  10  by the air turbine  12 , the polishing roll  30  is also driven. In this connection, the rotational direction of the polishing roll  30  is opposite to the rotational direction of the brush roll  10  which is indeed advantageous. Since the brush roll rotates toward the intake opening and the polishing roll has the opposite rotational direction, the kickback effect observed on hard floorings is avoided. In order to counteract this effect, it is known to carry out additional measures, for example, to provide a rubber lip; this is, however, an additional expenditure. The vacuuming power of conventional vacuum cleaning devices is large enough in order to prevent flinging of the vacuumed material. The force transmission from the brush roll  10  onto the polishing roll  30  is realized by the principle of a slipping clutch. Accordingly, a natural slip results as a function of the torques applied to the brush roll  10  and the polishing roll  30 . As a result of the continuous action of the bristles  10  onto the surface of the polishing roll  30  a cleaning effect for the polishing roll results and the removed dirt particles are entrained by the vacuum flow and carried away.  
         [0037]    [0037]FIG. 7 shows a longitudinal section of a first embodiment of the polishing roll  30  which is comprised of a central core  32  and a cover  34  enveloping it as a mantle. The cover  34  is preferably a textile covering that, depending on the requirements, is softer or harder, i.e., more wear resistant or more abrasive. The cover  34  is connected in the vicinity of its axial ends with the core  32 , in particular, by means of adhesive connections  33  so that the cover  34  is loose (unattached) relative to the core  32  in the area between the adhesive connections  33 . Bearing pins  35  are inserted into the end faces of the core  32 . The bearing pins  35  are received in corresponding bearings provided in the sidewalls of the vacuum shoe. When rotating the polishing roll  30  with a certain rotational speed, a centrifugal force acts on the textile material of the cover  34  by which the cover is radially expanded so that the polishing roll can thus treat uneven locations and cracks in the hard floor.  
         [0038]    Even though FIG. 6 shows that the drive of the polishing roll  30  can be realized by the bristles of the brush roll, FIG. 7 shows that it is also possible to drive the polishing roll  30  by the gear wheel  36  arranged at one end face, i.e., the drive of the polishing roll  30  is realized by means of an intermediate gear via the air turbine.  
         [0039]    [0039]FIG. 8 shows an end view of the second embodiment of the polishing roll in which a gear wheel at the end face is not required. As can be seen in FIG. 9, in this embodiment the polishing roll  30  has a core in the form of a tube  37 . Plugs  38  are inserted into its ends which receive the bearing pins  35 . The cover  34  in this embodiment is welded onto the entire surface of the tube  37  forming the core.  
         [0040]    [0040]FIG. 10 shows a perspective illustration of the vacuum cleaning tool according to FIG. 3 with a vertical section along the rotational axis of the polishing roll  30 . The polishing roll  30  is provided with bearings  41  whose bearing pins engage corresponding recesses or openings in the sidewalls  25  of the vacuum shoe  4 . The drive of the polishing roll  30  is realized in this embodiment by means of the rotating brush roll  10 .  
         [0041]    [0041]FIG. 11 shows a view in the direction of arrow XI of FIG. 10, however, with the lid of the housing being removed, so that the air turbine  12  with the turbine shaft  14  and the toothed belt wheel  15  are visible. The polishing roll  30  is comprised of the tube  37  with the cover  34  connected to its mantle surface. The bearings  41  are received in the end areas of the tube  37  and comprise bearing pins  45  which are axially displaceable by a certain amount against the force of a spring  43 . This movability toward the center of the tube  37  makes possible a simple exchange of the polishing roll  30 . The ends of the bearing pins  45  facing the sidewalls  25  engage elastic components  39  which are supported in recesses or openings of the sidewalls  25  so that a floating support of the polishing roll  30  is realized. The floating support has the advantage that the drive action via the bristles  11  of the brush roll  10  is automatically adjusted. This reduces the drive action of the polishing roll  30  when the vacuum cleaning tool  1  is lifted off, i.e., the slip between brush roll  10  and polishing roll  30  is increased, while the drive action is reinforced when the vacuum cleaning tool  1  is placed on the floor. A further advantage is that the polishing roll  30  is able to adjust better to the floor conditions as a result of this bearing action.  
         [0042]    [0042]FIG. 12 shows on an enlarged scale a section of the bearing  41  illustrated on the right side of FIG. 11. In the tube  37  of the polishing roll  30  a guide sleeve  44  for the axially movable bearing pin  45  is provided. Moreover, in the tube  37  a component is provided which comprises a spacer  47 , a support frame  48  as well as a securing portion  49  engaging behind the end of the tube  37 . The spacer  47  is provided to secure the position of the guide sleeve  44  relative to the end face of the polishing roll  30 . A ring  42  is arranged on the bearing pin  45  and is non-positively connected thereto. Between the ring  42  and an end face of the guide sleeve  44  a spring  43  is provided which, by being supported on the ring  42 , loads the bearing pin  45  in the direction toward the sidewall  25 . An elastic component  39  is supported on the support ring  48 . It comprises a sleeve  46  having a cap  46 ′ of a substantially part-spherical configuration and a radial flange  46 *. In this way, there is no direct contact of the bearing pin  45  on the sidewall  25 ; instead, the support action in any force direction is realized via the elastic component  39  so that a limited relative movement of the axis of the polishing roll  30  relative to the sidewall  25  is possible. Upon displacement of the ring  42  against the force of the spring  43 , the bearing pin  45  is moved out of the cap  46 ′ so that the end of the bearing pin  45  has a corresponding spacing to the cap  46 ′. As a result of the elasticity of the component  39  a deformation of the end of the sleeve  46  and of the cap  46 ′ is possible by which the positive-locking connection between the elastic component  39  and the sidewall  25  is canceled so that the polishing roll  30  can be removed. The mounting of a new polishing roll  30  is as simple as the removal because the polishing roll can be moved between the two sidewalls  25  illustrated in FIG. 11 as a result of the elastic deformation of the component  39  until the caps  46 ′ reach the region of the receiving opening  40  so that, as a result of the force of the spring  43 , the bearing pin  45  is moved automatically into the cap  46 ′ and secures it safely in the receiving opening  40  of the sidewall  25 .  
         [0043]    [0043]FIG. 13 shows an exploded view of the polishing roll  30  which is also provided with a gear wheel  36 , similar to that in FIG. 7, but is provided at the end faces with bearing pins  35  and plugs  38 , as shown in FIG. 9. This polishing roll  30  is driven via the to the gear wheel  36 , as illustrated in FIG. 14, in particular, by an intermediate gear wheel  51  arranged at the end face of the brush roll  10  which then meshes with the gear wheel  36 . Since the drive of the polishing roll  30  is thus realized by means of the gear wheels  36 ,  51 , the bristles  11  of the brush roll  10  are of such a length that they do not contact the mantle surface of the polishing roll  30 . For driving the complete arrangement, as described in connection with FIGS. 2 and 5, an air turbine  12  as well as a toothed belt  16  are provided. The vacuum shoe  24  corresponds to that of FIGS. 5 and 6.  
         [0044]    While specific embodiments of the invention have been shown and described in detail to illustrate the inventive principles, it will be understood that the invention may be embodied otherwise without departing from such principles.