Patent Abstract:
A drive belt shifting arrangement for a rotatable brush roller of an upright cleaner where the shifter has an idler pulley for arcuate movement within the loop of the belt between the roller and the motor occasioned by pedal actuation. The same pedal action by the user alternately cams the belt onto the idler pulley to discontinue roller rotation or to permit its movement back to the motor shaft to allow roller rotation.

Full Description:
[0001]    This application claims the benefit to U.S. provisional patent application entitled “BELT LIFTER MECHANISM FOR VACUUM CLEANER” having Ser. No. 61/043,213 filed Apr. 8, 2008, which is incorporated herein by reference in its entirety. 
     
    
     TECHNICAL FIELD 
       [0002]    The present disclosure relates to floor cleaning appliances with a belt shifting arrangement, more particularly to an upright cleaner such as vacuum cleaners, bare floor suction cleaners like extractors having a motor driven floor engaging roller brush. Some of these vacuum cleaners have a mechanism for disengaging the roller brush while continuing to run the motor for generating vacuum for cleaning as, for example, where it is desired to use hose attachments rather than the floor engaging roller brush. 
         [0003]    Heretofore, various mechanisms have been utilized for enabling the user to engage and disengage the roller brush; and, in particular, foot operated actuators have been provided for such engagement and disengagement for user convenience. An example of such a device is the belt lifter or shifter mechanism described in U.S. Pat. No. 6,067,689 in which a foot operated actuator is moved downwardly by foot pressure for disengagement and lifted up by pulling with the foot to move the actuator upwardly through an arc of up to about 110 degrees. This type of actuator movement, namely, the pulling upward with the user&#39;s foot in addition to the arcuate length of the foot movement, has been deemed to be somewhat awkward and, thus, it has been desired to improve the convenience of the engagement and disengagement of the roller brush in an upright vacuum cleaner. 
       BRIEF DESCRIPTION 
       [0004]    The present disclosure provides a belt lifter or engaging and disengaging mechanism for the roller brush of a floor cleaning appliance where in one embodiment is a vacuum cleaner, particularly an upright vacuum cleaner. The belt lifter or engaging and disengaging mechanism is provided in a manner which addresses the problems of the awkwardness of the foot operated actuator of the known vacuum cleaners. The belt lifter or clutching mechanism of the present disclosure utilizes a foot operated pedal having a relatively short stroke which enables the user to disengage the roller brush from the motor by a short downward stroke of the actuator and to engage the drive belt on the motor for driving the roller brush by a second relatively short downward stroke of the actuator. This provides a more convenient and user acceptable foot operated actuator for an upright vacuum cleaner where it is desired to disengage the roller brush drive while the vacuum motor continues to operate. 
         [0005]    In one embodiment of the present disclosure the belt lifter or shifter has a support mounting plate for attachment to the floor cleaning appliance, a arcuate movable clutch actuator with a user accessible pedal at one end, and clutch lever operatively associated with the actuator having a belt engaging arcuate surface. All three have openings sufficient for a motor shaft to pass through them where the openings can range from apertures to curved unconnected ends of each. The mounting plate has stops to limit the arcuate movement of the clutch lever and locking members to hold the idler pulley is either and engaged position with the belt or a disengaged position with the belt upon user activation of the pedal. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         [0006]      FIG. 1  is a perspective view of the roller brush drive train assembly for an upright vacuum cleaner in an exemplary embodiment with the drive belt disengaged; 
           [0007]      FIG. 2  is a view similar to  FIG. 1  with the mechanism moved to the position with the drive belt engaged for driving the roller brush; 
           [0008]      FIG. 3  is a front elevation view of the belt lift or clutching mechanism of the embodiment of  FIG. 1  in the disengaged position; 
           [0009]      FIG. 4  is a section view taken along section indicating line  4 - 4  of  FIG. 3 ; 
           [0010]      FIG. 5  is a view similar to  FIG. 3  showing the belt lifter mechanism in the position with the belt engaged as shown in  FIG. 2 ; 
           [0011]      FIG. 6  is a section view taken along section indicating line  6 - 6  of  FIG. 5 ; and, 
           [0012]      FIG. 7  is an exploded perspective view of the belt lifter or clutch mechanism of the present exemplary embodiment. 
           [0013]      FIG. 8  is a vacuum cleaning floor cleaning appliance that can have the roller brush drive train assembly with short stroke engaging and disengaging mechanism as shown in the other FIGURES. 
       
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS  
       [0014]    Before any embodiments of the inventive disclosure are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless specified or limited otherwise, the terms “mounted,” “connected,” “supported,” and “coupled” and variations thereof are used broadly and encompass both direct and indirect mountings, connections, supports, and couplings. Further, “connected” and “coupled” are not restricted to physical or mechanical connections or couplings. In addition other than where otherwise indicated, all numbers expressing quantities of physical properties and parameters and so forth used in the specification and claims are to be understood as being modified in all instances by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are approximations that may vary depending upon the desired properties sought to be obtained by the embodiments of the present invention. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical value should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Moreover, all ranges disclosed herein are to be understood to encompass the beginning and ending range values and any and all sub-ranges subsumed therein. 
         [0015]    Embodiments of the disclosure relate to floor cleaning appliances suitable examples are depicted in the drawings where similar parts and elements have the same reference number where appropriate.  FIG. 1  Referring to  FIG. 1 , a drive train for a belt driven roller brush of a vacuum cleaner is indicated generally at  10  and includes a vacuum generating drive motor  12  mounted to a portion of the vacuum cleaner structure  14  with a drive shaft  16  extending therethrough and outwardly thereof. A drive belt  18  operative to engage the motor shaft  16  engages a driven pulley  20  on a roller brush assembly indicated generally at  22  which is journalled for rotation on bearings  24 ,  26  provided on end plates  28 ,  30  which it will be understood are adapted for attachment to the vacuum cleaner structure (not shown). Known drive belts are typically formed of elastomeric material capable of about 25 percent elongation without breaking. Suitable non-exclusive examples of belts include flat belts, belts with v-shaped or u-shaped or rectangular cross-sectional shapes, cogged, and multiple longitudinal V-type belts, like Poly-V belts. The drive belt  18  is shown in  FIG. 1  as having an end opposite the roller brush pulley  20  disposed over an idler pulley  32 . Drive belt  18  may be stretched between motor shaft  16  and pulley  20 , such that it&#39;s natural elasticity maintains drive belt  18  under tension for transmitting power from motor  12  to brush roller  22 . The idler pulley  32 , as will hereinafter be described in detail, is mounted on a belt lifter or clutch mechanism indicated generally at  34 . As can be seen in  FIG. 7 , the lifter mechanism  34  includes a support frame or mounting plate  36  having an aperture  38  formed therein which is received over motor shaft  16  and secured to the vacuum cleaner structure  14 .  FIG. 1  shows the drive belt disengaged from the drive motor; and,  FIG. 2  shows the belt engaged with the motor for driving roller brush  22 . 
         [0016]    Referring to  FIGS. 3-7 , attached at one end of the mounting plate  36  is a support bracket  40 , by suitable fasteners as, for example, rivets  42 ,  44 . The bracket  40  has an end thereof extending generally parallel to the surface of plate  36  and with an aperture  46  formed therein adjacent the opposite free end. 
         [0017]    An actuator member indicated generally at  48 , has a pivot aperture  50  formed therein intermediate to the ends thereof. Received through the rivet aperture  50  is a retainer bushing  52  which has bearing surface  54  engaged in aperture  50 , with the lower end of the bushing  52  secured through the aperture  38  in frame  36  by any suitable expedient, as for example weldment or riveting or orbital staking. Thus, actuator  48  is free to pivot about bearing surface  54  when assembled to the frame  36 . With references to  FIGS. 1 and 2 , actuator  48  has a pedal  58  provided on the end of an arm  60  thereof for user depression. However, the pedal has been omitted from  FIGS. 3 through 7  for clarity of illustration. 
         [0018]    Actuator arm  60  has a tab or lug  62  formed thereon. Engaged on the lug  62  is one end  64  of a tension spring  66 , which has its opposite end  68  engaged with a similar tab  70  formed on the support frame  36 . Spring  66  thus biases the actuator  48  and arm  60  in a counterclockwise direction about the bushing  52 . 
         [0019]    A portion of actuator  48  disposed on the opposite side from arm  60  includes an arcuate slot  72  formed therein, which is generally of constant radius and concentric with the bushing bearing surface  54 . Actuator  48  also includes a second slot  74  with a generally rectangular configuration formed therein radially outwardly of the arcuate slot  72 . The configuration and disposition of the slots  72  and  74  are shown clearly in  FIG. 7 . 
         [0020]    A clutch lever indicated generally at  76  has a hub  78  formed thereon and extending axially therefrom on opposite sides thereof. Hub  78  is disposed between the free end of bracket  40  and the mounting frame  36 . A shouldered bolt  80  is received through hub  78  and aperture  46  in bracket  40  and through aperture  82  in frame  36  and is secured therein by any suitable expedient such as threaded nut  84 . Thus, clutch lever  76  is freely pivoted about the larger diameter portion of bolt  80 . A torsion spring  86  is provided about the hub  78  on lever  76  with one end of the torsion spring  88  engaging a projection  90  extending from lever  76 . An opposite end  92  of spring  86  engages the edge of bracket  40  in an arrangement which thus biases the lever  76  in a counterclockwise direction about the bolt  80 . 
         [0021]    Clutch lever  76  has on one end thereof, a projection or lug  94  extending from the inner face of the lever  76  and into the slot  74  on actuator  48  for limited lost motion movement therein. The end of lever  76  opposite lug  94  from hub  78  has a generally hooked or U-shaped configuration with the idler pulley  32  mounted on the end thereof by a suitable expedient. For example, bolt  93  extends through an aperture  96  in the end of the lever  76  and is retained thereon by nut  98 . A curved portion  95  of clutch lever  76  is configured to avoid interference with bushing  52  and the motor shaft  16  yet provide a wide arc of movement to the lever  76  for positioning idler pulley  32  on opposite sides of motor shaft  16  and centered on a line passing through the axis of motor shaft  16  and the axis of roller brush  22 . 
         [0022]    Mounting frame  36  has an arcuate slot  100  formed therein as shown in  FIGS. 3 ,  5  and  7 . Actuator member  48  has a tab or lug  102  formed thereon arcuately intermediate the arm  60  and slot  74 . Tab  102  extends into and engages slot  100  with the end  104  of tab  102  formed or bent to register in a sliding manner on the inner face of frame  36  for guiding movement of actuator  48 . 
         [0023]    The clutch lever  76  has a detent or locking surface  106  formed on the outer periphery thereof on the side opposite the curved portion  95 . The surface  106  extends generally radially with respect to bolt  80 . It is located intermediate the hub  78  and aperture  96  and serves an engaging function such as a latching function, as will hereinafter be described in greater detail. 
         [0024]    Also provided is a locking member  108 , having a generally L-shaped configuration. Member  108  has an aperture  110  formed at the junction of a pair of arms thereof or generally in the central region. The member  108  is pivotally mounted on frame  36  by a rivet  112  passing through aperture  110  in the lever and a corresponding aperture  114  formed in the frame  36 . Member  108  has a lug or tab  116 , which has one end  118  of a tension spring  120  engaged thereon. An opposite end  122  of spring  120  engages a corresponding lug or tab  124  provided on the edge of frame  36 . Spring  120  thus biases lever  108  in a counterclockwise direction pivotally about rivet  112 . 
         [0025]    The end of member  108  on the opposite side from spring  120  has a lug or tab  126  formed thereon. This tab extends through slot  128  formed in frame  36 , as shown in  FIGS. 3-6 , with the end of the tab  126  formed or configured to engage the inner surface of frame  36  in a sliding engagement. This design prevents a deflection of member  108  away from the frame  36 . Member  108  has another lug or tab  130  extending therefrom on the end thereof adjacent tab  126 . The tab or lug  130  extends from the member  108  in the direction away from plate  36 , and has a right angle formed at the end  132  thereof. The end  132  of tab  130  serves to engage the latching surface  106  on clutch lever  76  as will hereinafter be described. 
         [0026]    Referring to  FIG. 7 , an actuator stop member  134  is pivotally mounted on locking member  108  by a fastener such as rivet  136  passing through aperture  138  formed in the member  134  and an aligned aperture  140  formed in the member  108 . A spacer washer  142  is disposed between the stop member  134  and locking member  108 , which facilitates free rotation of the stop member upon rivet  136  mounted on the locking member  108 . A clearance slot  144  is provided in support frame  36  to permit movement of the end of the rivet as the locking member  108  moves to prevent the end of the rivet from engaging the frame  36 . Stop member  134  has a tab  146  formed on an end thereof, which extends downwardly toward the member  108 . It is operative to engage the edge of member  108 , as will hereinafter be described. The end of stop member  134  on the opposite side of the aperture  138  from tab  146  has a pawl  148  formed thereon. The pawl  148  serves to be engaged by a downwardly extending tab  150  formed on the actuator arm  60  of actuator  48 , in a manner which will hereinafter be described. 
         [0027]    Actuator stop member  134  also has an upwardly extending tab or lug  152  formed thereon intermediate the tab  146  and pawl  148 . The tab  152  is used to mount  5  one end  154  of a tension spring  156 . Referring to  FIG. 3 , the opposite end of spring  156  is connected to a tab  158  provided on the locking member  108 , which tab  158  is positioned at a relatively short distance from rivet  112 . Spring  156  is operative to bias the stop member  134  in a counterclockwise direction about the rivet  136 . 
         [0028]    Referring to  FIGS. 2 and 5 , the clutch mechanism  34  is shown with the belt  18  engaging the motor shaft  16 , with the belt shown in dashed outline in  FIG. 5 . The clutch actuator lever  48  is shown rotated to its fully counterclockwise position in solid outline. Further movement thereof is prevented by the tab  152  engaging the upper end of the slot  100  formed in the frame  36 . The clutch lever  76  is rotated to its fully counterclockwise position under the urging of torsion spring  86 , with the lug  94  on lever  76  engaging the right hand side of slot  74  in the actuator lever  48 , thereby preventing further movement of the member  76 . 
         [0029]    When the operator of the vacuum cleaner desires to disengage the roller brush  22  from the drive motor, the operator depresses the pedal  58  to push the arm  60  downwardly, effecting clockwise rotation of the actuator member  48  about the bushing  54 . This causes the slot  74  of the actuator arm  48  to bear against the lug  94  and rotate the clutch lever  76  in a clockwise direction about the bolt  80 . Such movement causes a cam surface  160  on the clutch lever  76  to bear against the tab  130  on member  108 . This movement lifts the tab  130  to the position shown in dashed outline, by clockwise rotation of the member  108  about rivet  112 . Further downward movement of arm  60  causes the slot  74  in the actuator  48  to move the clutch lever  76  to the position shown in solid outline in  FIG. 3  whereupon the bias of spring  120  causes member  108  to rotate in the counterclockwise direction, causing tab  132  to engage the locking surface  106  on clutch arm  76 . Thus, the clutch lever  76  is locked into the position shown in solid outline in  FIG. 3  thereby disengaging the belt  18  from the motor shaft  16  by contact of the idler pulley  32  with the belt  18 . 
         [0030]    Upon the user releasing pressure from pedal  58 , arm  60  moves from the position shown in solid outline in  FIG. 3  upwardly to the position shown in dashed outline. Further counterclockwise rotation of the member  48  is prevented by engagement of the left side of slot  74  with the lug  94  on the clutch lever as shown in dashed outline in  FIG. 3.6   
         [0031]    It will be understood that during the belt disengagement movement, the belt  18  is stretched from the position shown in  FIGS. 2 and 5  to the length shown in  FIGS. 1 and 3 , by virtue of the elastomeric nature of the material of the drive belt  18 . 
         [0032]    When the user desires to re-engage the driving of the roller brush  22 , the lever arm  60  of actuator  48  is moved by the user depressing pedal  58  to move the actuator  48  including arm  60  from the position shown in dashed outline in  FIG. 3  to the lowered or clockwise rotated position shown in solid outline, whereupon the lug or tab  54  on arm  60  engages the pawl  148  on stop member  134  and rotates the member  134  in a clockwise direction until the tab  146  thereon engages the inner edge of the lower portion of member  108  as shown in dashed outline in  FIG. 5 , whereupon further downward movement of arm  60  and clockwise rotation of actuator  48  is prevented. Concurrently with the rotation of stop member  134  on arm locking member  108 , the downward movement of the stop member  134  causes arm locking member  108  to pivot about rivet  112  and lift the tab  130  on the opposite end of locking member  108  from engagement with the locking surface  106  in on the clutch lever  76 . 
         [0033]    With the tab  134  disengaged from the locking surface  106 , the line of action of the tension forces of opposing sides of the belt on the pulley  32  acts along the line AA in  FIG. 3  (e.g. through the center of the roller brush  22 ). This line of action causes a counterclockwise moment on the clutch lever  76  about the bolt  80  causing sudden free movement of clutch lever  76  to the engaged position as shown in  FIG. 5 , thereby re-engaging the belt with the motor shaft  16 . The counterclockwise movement of the clutch lever  76  to the position shown in  FIG. 5  causes the lug  94  on clutch lever  76  to engage the right hand edge of slot  74  in actuator  48  and rotate the actuator counterclockwise to the return position shown in solid outline in  FIG. 5 , when the user releases pressure from the pedal  58 . 
         [0034]    As shown in  FIG. 8  in general according to an embodiment of the inventive disclosure an upright cleaner includes a floor engaging portion  170 , and a handle portion  172  pivotally mounted with the floor engaging portion for pivotal motion relative to the floor engaging portion between a generally upright stationary position and an inclined pivotal operating position. A brush roller  22  or sometimes referred to as an agitator or beater bar is rotatably mounted in the floor engaging portion  170  for agitating a floor surface being cleaned. Also within portion  170  can be the drive motor  12  with the motor output shaft  16  and an brush roller belt  18  selectively drivingly connecting the motor to the brush roller. The engaging and disengaging mechanism as for the above-described embodiments such as those of  FIGS. 1-7  are also positioned in the floor engaging portion  170 . With this arrangement the drive motor can be separate from any suction source and motor for the upright cleaner. Alternatively the motor for the suction source can also be the motor for the belt drive for the brush roller. In such a case the motor is arranged such that a rotor shaft extends horizontally and out both ends of motor housing. A conventional fan (not shown) may be affixed to one end of rotor shaft (not shown) for generating suction. The other end of the rotor shaft is utilized to drive any transmission and brush roller  22  via a drive belt  18 . The upright cleaner  168  can be manually propelled or self-propelled in which case the floor engaging portion  170  would also house the drive transmission. The details of the transmission  18  do not form a part of the present invention and are therefore not disclosed in detail herein. However, a suitable transmission for use with a self-propelled upright vacuum cleaner according to the present invention is disclosed in U.S. Pat. No. 3,581,591, the disclosure of which is hereby incorporated herein as of reference. 
         [0035]    The floor engaging portion  170  also referred to as a foot usually includes a floor nozzle  174  that is fluidly connected to a dirt receptacle and the suction source (not shown). Freely rotating support wheels  176  (only one of which is visible in  FIG. 8  are located to the rear and on opposite sides of the floor engaging portion  170 . An upper housing  178  with handle portion  172  or just the handle portion  172  is pivotally mounted to the lower portion  170  in a conventional manner for pivotal motion from a generally upright stationary position, to an inclined pivotal operating position. A hand grip  180  may be slidably mounted to the top end of upper housing  178  for limited reciprocal motion relative thereto for any electronic controls such as an off/on switch (not shown). The nozzle body, generally indicated as  182 , defines a transversely extending brush roller chamber  184  having a downward opening nozzle or suction opening  174 . A rotary brush roller  22  is rotatably mounted in chamber  184  in a conventional manner with its bristles usually extending out nozzle opening  174  for agitating a surface to be cleaned. 
         [0036]    The present disclosure thus describes a belt lifter or clutch mechanism for engaging and disengaging the roller brush of an upright vacuum cleaner in which the user need only effect a short push stroke of a foot pedal to disengage the roller brush from the motor; and, upon release, the pedal returns to a ready position. The user need only apply another short push stroke to release the mechanism and re-engage the belt  7  from the roller brush to the drive motor. The mechanism of the present disclosure thus provides a simple and easy to use clutching mechanism for enabling the user of an upright vacuum cleaner to disengage the roller brush from the drive motor and continue operation of the drive motor and vacuum generating unit to enable use of attachments for vacuuming. 
         [0037]    The exemplary embodiment has been described with reference to the drawings presented. Obviously, modifications and alterations will occur to others upon reading and understanding the preceding detailed description. It is intended that the exemplary embodiment be construed as including all such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.

Technology Classification (CPC): 0