Abstract:
A vacuum cleaning apparatus includes a vacuum cleaner base and a handle configured to be attached to the base. A nozzle is configured for the base to draw air through the nozzle to clean the floor as the nozzle is moved along the floor by a user pushing the base by the handle. A power head assembly includes a power head having a brushroll and an electric motor that drives the brushroll. The assembly further includes a tube structure configured to connect the power head to the base for the base to draw air through the power head and the tube structure to clean the floor as the power head is moved along the floor by a user pushing the tube structure.

Description:
TECHNICAL FIELD 
   This application relates to vacuum cleaners. 
   BACKGROUND 
   A vacuum cleaner includes a base and a nozzle. The nozzle can be removably attached to the base for vacuuming a carpeted floor. 
   SUMMARY 
   A vacuum cleaning apparatus includes a vacuum cleaner base and a handle configured to be attached to the base. A nozzle is configured for the base to draw air through the nozzle to clean the floor as the nozzle is moved along the floor by a user pushing the base by the handle. A power head assembly includes a power head having a brushroll and an electric motor that drives the brushroll. The assembly further includes a tube structure configured to connect the power head to the base for the base to draw air through the power head and the tube structure to clean the floor as the power head is moved along the floor by a user pushing the tube structure. 
   Preferably, the handle is configured to be removably attached to the base. The tube structure has a flexible tube enabling the power head to be manually moved independent of the base. The base is configured to sense which one of the nozzle and the power head assembly is attached to the base and control an operating condition of the base based on which one is attached to the base. The nozzle includes a brushroll. The base has a drive pulley for driving the brushroll of the nozzle. The base is configured to rotate the drive pulley when the nozzle is attached to the base but not when the power head assembly is attached to the base. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view of a base unit of a vacuum cleaner and various cleaning attachments that can be removably attached to it, including a nozzle, a power head assembly and an accessory hose; 
       FIG. 2  is a perspective view of the base unit, showing its external parts; 
       FIG. 3  is a perspective view of the base unit, showing its internal parts; 
       FIG. 4  is a perspective view of the base unit attached to the nozzle; 
       FIG. 5  is a perspective view illustrating a procedure for attaching the hose to the base unit; 
       FIG. 6  is a perspective view of the base unit attached to the power head assembly; 
       FIG. 7  is a rear perspective view of the nozzle; and 
       FIG. 8  is a rear perspective view of a part of the power head assembly. 
   

   DESCRIPTION 
   Overview 
   The apparatus shown in  FIG. 1  has parts that are examples of the elements recited in the claims. The apparatus thus includes examples of how a person of ordinary skill in the art can make and use the claimed invention. It is described here to meet the requirements of enablement and best mode without imposing limitations that are not recited in the claims. 
   The apparatus shown in  FIG. 1  is used for cleaning household surfaces, such as a carpeted floor  6 . The apparatus includes a base unit  10  and three cleaning attachments—a nozzle  12 , a power head assembly  14  and an accessory hose  16 . The nozzle  12  and the power head assembly  14  can be removably attached to the base unit  10  for vacuuming the floor  6 . The hose  16  can be removably attached to the base unit  10  for vacuuming above-the-floor household surfaces. The base unit  10  with the three cleaning attachments  12 ,  14  and  16  can be sold as a set to a single buyer, who can use each attachment with the base as desired. 
   Base Unit 
   The base unit  10  comprises a base  20 , a handle  22  pivotably connected to the base  20 , and a filter bag  24  supported by the handle  22 . 
   The handle  22  in this example is an “upright handle” by which a user, while standing, pushes the base  20  over the floor  6 . The handle  22  is permanently attached to the base  20  in this example, but can instead be removably attached to the base  20 . 
   As shown in  FIG. 2 , the base  20  has a housing  30 . The housing  30  has a front face  40  with upper and lower inlet ports  46  and  48 . Front wheels  50  and rear wheels  52  are rotatable connected to the housing  30  for wheeling the base  20  over the floor  6 . The base  20  has two perch pins  60  and a bear claw latch  64  with a release button  66 , for securing the cleaning attachments to the base  20 . It also has four electrical contacts  71 ,  72 ,  73  and  74 —respectively designated ground, 5VDC-out, 24VDC-out and resistance-sense. A front pushbutton switch  76  on the housing  30  senses whether the upper inlet port  46  is covered by a cleaning attachment. 
   As shown in  FIG. 3 , a centrifugal fan  80  in the housing  30  has an inlet  82  connected to the inlet ports  46  and  48  and an outlet  84  connected to the filter bag  24 . The fan  80  is driven by a motor  88 . The motor  88  also drives a toothed drive pulley  90  through a drive train that includes shafts  93 , belts  94 , pulleys  95 , a bevel gear  96  and an electrically actuated clutch  98 . A drive assist motor  99  rotates the rear wheels  52  to propel the base  20 . A rear pushbutton switch  120  senses whether the handle  22  is in an upright or inclined position. 
   A controller circuit  130  is electrically connected to the electrical components  71 - 74 ,  76 ,  88 ,  98 ,  99 ,  120  and  124  ( FIGS. 2 and 3 ) of the base  20  to monitor and control operation of the base  20 . 
   The circuit  130  receives wall current through a power cord  132 . It generates a 5VDC and 24VDC supply that is output through the 5VDC-out and 24VDC-out contacts  72  and  73 . It senses electrical resistance applied across the sense contact  74  and ground contact  71  by whichever attachment is installed on the base  20 . Since each attachment applies a unique resistance, the controller  130  can determine which attachment, if any, is installed. 
   The controller  130  powers the motor  88  only when a power switch  140  ( FIG. 1 ) on the handle  22  is switched on and the front switch  76  is depressed. The controller  130  engages the clutch  98  to couple the motor  88  to the drive pulley  90  only while the nozzle  12  is installed, and not when the power head  14  is installed. When the handle  22  is inclined, the controller  130  powers the drive assist motor  99  to rotate the rear wheels  52  in a direction and at a speed that correspond respectively to the direction and magnitude of the force manually applied to the handle  22 , to assist the user in moving the base  20  over the floor  6 . 
   Nozzle 
     FIG. 4  shows an upright vacuum cleaner  300  comprising the nozzle  12  attached to the base unit  10 . This type of cleaner is configured for the user to manually push the cleaner  300  by its handle  22  over the floor  6  to clean the floor  6 . The nozzle  12  is supported by the base  20  to move with the base  20  as the base  20  is pushed by its handle  22 . 
   The nozzle  12  has a brushroll  302  driven by the drive pulley  90  ( FIG. 2 ) to rotate against the floor  6  to dislodge dirt from the floor  6 . The fan  80  generates an air flow that carries the dirt from the floor  6 , through the nozzle  12 , the lower inlet ports  48  ( FIG. 2 ) and the fan  80 , into the filter bag  24 . The nozzle  12  has a door  350  that covers and blocks the base&#39;s upper inlet port  46 . A headlight  310  on the nozzle  12  illuminates the floor  6  in front of the cleaner  300 . The headlight  310  is powered by electricity supplied by the base  20  through the base&#39;s ground and 5VDC-out contacts  71  and  72  ( FIG. 2 ). 
   Accessory Hose 
   As shown in  FIG. 5 , the hose  16  is configured to connect a hose accessory, such as a brush attachment  390 , to the base  20 . The hose  16  includes a flexible tube  392  and a rigid connector  394 . 
   The hose  16  can be installed on the base  20  without removing the nozzle  12 . This is done by opening the door  350  (arrow  395 ) and inserting the hose connector  394  into the upper inlet port  46  (arrow  397 ). A prong  398  projecting from the connector  394  engages the base&#39;s front switch  76 . Within the base  20 , the connector  394  conducts air from the hose  16  into the fan inlet  82  while isolating the nozzle  12  from the fan inlet  12 . 
   The hose  16  can also be installed on the base  20 , by simply inserting the hose connector  394  into the upper inlet port  46 , without the nozzle  12  present. In this configuration, the controller  130  determines, by the lack of an applied resistance across the base&#39;s ground and sense contacts  71  and  74 , that a cleaning head is not installed. The controller  130  then disengages the clutch  98  ( FIG. 3 ) to uncouple the drive pulley  90  from the motor  88 . 
   Power Head Assembly 
     FIG. 6  shows a canister type vacuum cleaner  500  comprising the power head assembly  14  attached to the base  20 . This type of cleaner is configured for the base  20  to be pulled over the floor  6  by the assembly  14  as the user pushes the assembly  14  over the floor  6  to clean the floor  6 . 
   The power head assembly  14  includes a power head  510  with a brushroll  512  driven by a motor  514 . A rigid tube  520 , with a handgrip  522 , is pivotably connected to the power head  510 . The rigid tube  520  is connected by a flexible tube  530  to a connector  540  that is removably attachable to the base  20 . 
   A headlamp  550  on the power head  510  illuminates the floor  6  in front of the power head  510 . The headlamp  550  and the motor  514  are respectively powered by 5VDC and 24VDC from the electrical contacts  71 - 73  ( FIG. 2 ) of the base  20 , through a power switch  560  in the handgrip  522 . 
   In operation, a user grasps the handgrip  522  to both push the power head  510  over the floor  6  and pull the base  20  by the flexible tube  530 . The flexible tube  530  enables the power head to be moved independently of the base  20  within an area limited by the length of the flexible tube  530 . The brushroll  512  rotates against the floor  6  to dislodge dirt. The fan  80  generates an air flow that carries the dirt from the floor  6 , through the power head assembly  14 , the upper inlet port  46  ( FIG. 2 ) and the fan  80 , into the filter bag  24 . 
   The nozzle  12  ( FIG. 4 ) and the power head connector  540  are both specifically designed by the manufacturer to be attachable to the particular base  20  shown in  FIG. 2 . Accordingly, the nozzle  12  and the connector  540  have similar structures that are uniquely sized, shaped and positioned for interconnection with the base  20 . These structures include, as apparent by comparing  FIG. 7  to  FIG. 8  in view of  FIG. 2 , perch hooks  660  and  660 ′ that hook onto the base&#39;s perch pins  60 , a latch pin  664  and  664 ′ grasped by the base&#39;s latch  64 , electrical contacts  671 - 674  and  671 ′- 674 ′ that electrically contact the base&#39;s contacts  71 - 74 , and a prong  676  and  676 ′ that presses the base&#39;s front switch  76 . 
   This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to make and use the invention. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.