Abstract:
A vacuum cleaner includes a base having first and second inlet ports and a fan configured to draw air through the inlet ports into the base. A vacuuming head is removably attachable to the base to channel air from a surface into the first inlet port to clean the surface while covering and blocking the second inlet port. An attachment, different than the head, is removably attachable to the base to channel air into the second inlet port.

Description:
TECHNICAL FIELD 
     This application relates to vacuum cleaners. 
     BACKGROUND 
     A vacuum cleaner includes a base and a vacuuming head. The vacuuming head can be removably attached to the base for vacuuming a carpet. 
     SUMMARY 
     A vacuum cleaner includes a base having first and second inlet ports and a fan configured to draw air through the inlet ports into the base. A vacuuming head is removably attachable to the base to channel air from a surface into the first inlet port to clean the surface while covering and blocking the second inlet port. An attachment, different than the head, is removably attachable to the base to channel air into the second inlet port. 
     The attachment can be configured to cover and block the first inlet port when the attachment is removably attached to the base. The fan can have an inlet through which the fan draws air from the inlet ports, and the attachment can be configured to be inserted through second inlet port and, within the base, isolate the first inlet port from the fan inlet. Both inlet ports are preferably at a front end of the base. 
     Another vacuum cleaner has a base with a front end, first and second inlet ports in the front end and an impeller behind the ports. The base defines a first flow path extending continuously rearward from the first inlet port to the impeller and a second flow path extending continuously rearward from the second inlet port to the impeller. A vacuuming head is removably attachable to the base to conduct air from a surface into the first inlet port to clean the surface. An attachment, different than the head, is removably attachable to the base to conduct air into the second inlet port. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a vacuum cleaner base with a handle and a filter bag, and various cleaning attachments that can be removably attached to the base, including a vacuuming head, a power head assembly and an accessory hose; 
         FIG. 2  is a perspective view of the base, showing its external parts; 
         FIG. 3  is a perspective view of the base, showing its internal parts; 
         FIG. 4  is a front perspective view of the vacuuming head shown attached to the base; 
         FIG. 5  is a rear perspective view of the vacuuming head; 
         FIG. 6  is a side sectional view illustrating a procedure for attaching the vacuuming head to the base; 
         FIG. 7  is a side sectional view of the vacuuming head attached to the base; 
         FIG. 8  is a perspective view illustrating operation of the vacuuming head and the base; 
         FIG. 9  is a perspective view illustrating a procedure for attaching the hose to the base; 
         FIG. 10  is a side sectional view of both the hose and the vacuuming head attached to the base; 
         FIG. 11  is a side sectional view of the hose attached to the base without the vacuuming head; 
         FIG. 12  is a perspective view of the power head assembly attached to the base; 
         FIG. 13  is a perspective view of a portion of the power head assembly; 
         FIG. 14  is a side sectional view illustrating a procedure for attaching the power head assembly to the base; and 
         FIG. 15  is a side sectional view of the power head assembly attached to the base. 
     
    
    
     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 a carpeted floor  6 . The apparatus includes a base unit  10  and three cleaning attachments for cleaning household surfaces—a vacuuming head  12 , a power head assembly  14  and an accessory hose  16 . The vacuuming head  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. 
     Base 
     The base unit  10  comprises a base  20 , a handle  22  extending upward from the base  20 , and a filter bag  24  supported by the handle  22 . 
     As shown in  FIG. 2 , the base  20  has a housing  30  located on an axis  31 . The housing  30  has axially front and rear ends  36  and  38 . At the front end  36 , the housing  30  has a front face  40  and a platform  42  projecting forward from the front face  40 . A pocket  45  is transversely centered in the front face  40  and the platform  42 . The front face  40  defines an upper inlet port  46  above the pocket  45  and two lower inlet ports  48  on either side of the pocket  45 . Each inlet port  46  and  48  is surrounded by a rubber gasket  49 . 
     Two front wheels  50  and two rear wheels  52  are respectively rotatable about parallel axes  53  and  55  for wheeling the base  20  over the floor  6 . The rear wheels  52  are fixed to a common rear axle  56  that is rotatably connected to the housing  30 . The front wheels  50  are rotatably connected to the housing  30  by a height-adjust mechanism  58  that enables a user to raise and lower the front end  36  relative to the floor  6 . 
     Two transversely extending perch pins  60  are attached to the platform  42  by two pairs of support arms  62 . A bear claw latch  64 , with a release button  66 , is attached to the top of the housing  30 . Four electrical contacts  71 ,  72 ,  73  and  74 —respectively designated ground, 5VDC-out, 24VDC-out and resistance-sense—are fixed to the platform  42 . An attachment sensor  76  on the housing  30 , in this example a pushbutton switch, 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 by a fill tube  86  to the filter bag  24 . The fan  80  further has an impeller  87  rotatable about the axis  31  and driven by a motor  88 . 
     A toothed drive pulley  90  is located in the pocket  45  and is rotatable about a transversely extending rotational axis  91 . The drive pulley  90  is driven by the motor  88  through a drive train that includes shafts  93 , belts  94 , pulleys  95 , a bevel gear  96  and an electrically actuated clutch  98 . 
     A controller circuit  100  is electrically connected to the electrical components  71 - 74 ,  76 ,  88 ,  98  of the base  20 , shown in  FIGS. 2-3 , to monitor and control operation of the base  20 . The circuit  100  receives wall current through a power cord  102 . It generates a 5VDC supply and a 24VDC supply that are output respectively through the 5VDC-out contact  72  and the 24VDC-out contact  73 . It senses electrical resistance applied across the sense contact  74  and ground contact  71  by whichever head  12  or  14  is installed on the base  20 . Since each cleaning head applies a unique resistance, the controller  100  can determine which head, if any, is attached. 
     The controller  100  monitors a toggle-type power switch  104  ( FIG. 1 ) in the handle  22  and turns the motor  88  alternately on and off each time the switch  104  is pressed. The circuit  100  refrains from powering the motor  88  when no cleaning attachment is installed or the upper inlet port  46  is uncovered, as determined by the attachment sensor  76 . If a cleaning attachment is detached while the motor  88  is running, the controller  100  will immediately cease powering the motor  88  until the attachment is reattached as indicated by the sensor  76  and the power switch  104  is pressed. 
     If a cleaning attachment different from the vacuuming nozzle  12  is installed, as determined through the resistance-sense contact  74 , the controller  100  will power the motor  88  when the power switch  104  is pressed but keep the clutch  98  disengaged, which disengages the drive pulley  90  from the motor  88 . This enables the motor  88  to drive the fan  80  without driving the drive pulley  90 . 
     Vacuuming Head 
       FIG. 4  shows a vacuum cleaner  300  comprising the vacuuming head  12  attached to the base unit  10 . The vacuuming head  12  includes a housing  304  with front and rear ends  306  and  308 . A headlamp  310  at the front end  306  is configured to illuminate the floor  6  in front of the head  12 . 
     As shown in  FIG. 5 , the housing  304  defines a nozzle cavity  321  and rotatably supports a brushroll  322  in the cavity  321 . The brushroll  322  includes a dowel  324  and bristles  326  projecting from the dowel  324 . The dowel  324  has a poly-V surface section  328  and is rotatable about an axis  329 . 
     A drive coupling assembly  330  is configured to couple the brushroll  322  to the drive pulley  90  ( FIG. 2 ) of the base  20  for the drive pulley  90  to drive the brushroll  322 . The coupling assembly  330  includes an idler pulley  332  located outside the nozzle cavity  321  and rotatable about an axis  333  parallel to the brushroll axis  329 . The idler pulley  332  is mounted to the housing  304  by an elastically flexible arm  335  cantilevered from the housing  304 . A belt  336  extends permanently about the brushroll  322  and the idler pulley  332  and is thus partially inside and partially outside the nozzle cavity  321 . The belt  336  has a poly-V inner surface  337  and a gear-toothed outer surface  338 . 
     Three electrical contacts  341 ,  342 ,  343 —ground, power-in, and resistance-out—are attached to the rear  308  of the housing  304 . They are configured to respectively contact the ground, 5VDC-out and resistance sense contacts  71 ,  72  and  74  ( FIG. 2 ) of the base  20 . The ground and power-in contacts  341  and  342  are electrically connected to the headlamp  310  ( FIG. 4 ) to power the headlamp  310  with 5VDC supplied by the base  20 . The ground and resistance-out contacts  341  and  343  are connected across a resistor (not shown) in the head  12  with a resistance value that is unique to the vacuuming head  12 . 
     A latch pin  346  and two perch hooks  348  are adjoined to the rear  308  of the housing  304  for attaching the head  12  to the base  20 . A door  350  is pivotably connected to the housing  304  by a hinge  352  ( FIG. 4 ) to cover an upper opening  354  in the housing  304 . A sealing surface  356  of the door  350  is configured to sealingly engage the upper gasket  49  of the base  20  ( FIG. 2 ). A prong  358  projecting from the door  350  is configured to press the sensor switch  76  when the head  12  is attached to the base  20  and the door  350  is closed. Air enters the nozzle cavity  321  through an inlet opening  359  and exits the nozzle cavity  321  through two outlet openings  360 . The outlet openings  360  are surrounded by sealing surfaces  362  configured to sealingly engage the two lower gaskets  49  of the base  20 . 
       FIG. 6  illustrates a procedure for attaching the head  12  to the base  20 . First, the perch hooks  348  are mounted onto the perch pins  60  of the base  20 . The arms  62  ( FIG. 2 ) of the base  20  abut two opposite sides of the perch hooks  348  to keep the head  12  transversely centered on the base  20 . Then, the head  12  is pivoted (arrow  371 ) rearward about the perch pins  60  until the latch pin  346  is captured by the latch  64  of the base  20  as shown in  FIG. 7 . The head  12  is thus removably attached to the base  20  in an installed position. The height-adjustment mechanism  58  can be adjusted to bring the brushroll bristles  326  into contact with the floor  6 . 
     In the installation procedure shown in  FIG. 6 , the pivotal movement (arrow  371 ) of the head  12  toward and into the installed position moves the belt  336  toward and into engagement with the drive pulley  90 , and also moves the contacts  341 ,  342  and  343  of the head  12  toward and into electrical contact with the contacts  71 ,  72  and  73  of the base  20 , and further moves the sealing surfaces  356  and  362  of the head  12  into sealing contact with the three gaskets  49  of the base  20 . The perch pins  60  facilitate the installation procedure by supporting the weight of the head  12  and by keeping components of the head  12  properly aligned with mating components of the base  20  while the head  12  is pivoted. 
     With the head  12  in its installed position as shown in  FIG. 7 , the following features are apparent: The head  12  is configured to channel air from the floor  6  into the lower inlet ports  48  while its door  350  covers and blocks the upper inlet port  46 . The respective rotational axes  53 ,  55 ,  91 ,  329  and  333  of the front and rear wheels  50  and  52 , the drive pulley  90 , the brushroll  322  and the idler pulley  332  are all horizontal and parallel to each other and to the perch pins  60 . They are all also perpendicular to movement of the base  20  as it is pushed forward and pulled rearward over the floor  6 . The belt&#39;s poly-V inner surface  337  engages the idler pulley  332  and the poly-V surface  328  of the brushroll  322 . The brushroll axis  329  and the idler pulley axis  333  are at opposite sides of the drive pulley axis  91 , respectively in front of and behind the drive pulley axis  91 . This enables the idler pulley  332  and the brushroll  322  to together pull the belt&#39;s toothed outer surface  338  down against, and partially about, the drive pulley  90 . 
     The elastic pulley mounting arm  335  applies to the idler pulley  332  an elastic force pulling the belt  336  down against the drive pulley  90 . The elastic nature of the pull force enables the position of the idler pulley  332  to adjust to variation in length of the belt  336  to maintain tension of the belt  336  against the drive pulley  90 . 
     To detach the head  12  from the base  20 , the latch release button  66  is pressed to release the latch pin  346 . Then, the head  12  is pivoted away from the base  20  and lifted from the perch pins  60 . 
     As shown in  FIG. 8 , the base  20 , handle  22 , bag  24  and vacuuming head  12  together comprise an upright vacuum cleaner  300 . When the power switch  104  ( FIG. 1 ) is pressed, the controller  100  powers the motor  88 . The motor shaft  380  directly drives the impeller  87 . It indirectly drives the brushroll  322  through a sequence of moving parts comprising the drive pulley  90 , the drive belt  336 , the shafts  93 , the other belts  94  and pulleys  95 , the bevel gear  96 , and rotating parts of the clutch  98 . 
     As the user moves the cleaner  300  over the floor  6 , the brushroll  322  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 nozzle cavity  321 , the lower inlet ports  48  and the fan  80 , into the filter bag  24 . This route includes a split first flow path  381  extending from the head&#39;s inlet  359  to the base&#39;s lower inlet ports  48 . The route further includes a split second flow path  382  extending continuously rearward from the lower inlet ports  48  to the impeller  87 . The continuously-rearward character of the second flow path  382  is beneficial to flow efficiency. The efficiency is further benefited by the split second path  382  fully including two imaginary straight lines L 2  extending, unobstructed, respectively from the two lower inlet ports  48  to the impeller  87 . 
     As shown in  FIG. 8 , the sequence of moving parts conveying rotation of the motor shaft  380  to the brushroll  322  is spaced from, and does not extend through, the inlet ports  46  and  48  and the flow paths  381  and  382 . The drive belt  336  is isolated from the first flow path  381  by a casing  386  that is part of the head housing  304 . 
     Accessory Hose 
     As shown in  FIG. 9 , 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  extending from a rigid scoop-shaped connector  394 . A prong  398  projecting from the connector  394  is configured to engage the attachment sensor  76 . The hose  16  can be installed on the base  20  by manually opening the door  350  (arrow  395 ) away from the upper inlet port  46 , and inserting the hose connector  394  into the upper inlet port  46  (arrow  397 ) until the hose  16  is in an installed position shown in  FIG. 10 . 
     Within the base  20 , the connector  394  sealingly engages the fan  80  and the base housing  30  to isolate the fan inlet  82  from the lower inlet ports  48 , to block air from flowing from the lower inlet ports  48  to the fan inlet  82 . 
     When the power switch  104  ( FIG. 1 ) is pressed, the controller  100  powers the motor  88  to drive the fan  80 . The fan  80  generates a flow of air that carries dirt from the surface being cleaned, through the hose  16 , the upper inlet port  46  and the fan  80  into the bag  24  ( FIG. 9 ). Preferably, this route includes a flow path  399  that extends continuously rearward from the upper inlet port  46  through the fan inlet  82  to the impeller  87 . This path  399  fully includes an imaginary straight line L 1  extending, unobstructed, from the upper inlet port  46  through the fan inlet  82  to the impeller  87 . 
     As shown in  FIG. 11 , the hose  16  can be installed on the base  20  without the vacuuming head  12  and function as described above. By the lack of an applied resistance across the ground and resistance-sense contacts  71  and  74 , the controller  100  determines that a head is not installed and disengages the clutch  98  ( FIG. 3 ), and thus disengages the drive pulley  90  from the motor  88 . 
     The hose  16  in this example is a cleaning attachment in that it is for cleaning household surfaces. In another example, the attachment is a vacuum powered tool that is not for cleaning, such as a vacuum powered sander. The sander can include an air motor that rotates a sanding disk and is connected to a tube that is removably insertable into the upper inlet port. Like the hose  16 , the vacuum powered tool can be installed on the base  20  whether the vacuuming head  12  is installed or is absent. 
     Power Head Assembly 
       FIG. 12  shows the power head assembly  14  attached to the base  20 . The power head assembly  14  includes a power head  510 , connected by a rigid tube  514  and a flexible tube  516  to an attachment plate connector  518 . 
     The power head  510  includes a housing  520  defining a nozzle cavity  521 . A headlamp  524  is secured to a front end of the housing  520 . A brushroll  530  in the nozzle cavity  520  is driven by a motor  534  in the housing  520 . The rigid tube  514  is pivotably connected to the power head  510  and has a handgrip  540 , so that the tube  514  can be used as a handle for pushing the power head  510  over the floor  6 . 
     As shown in  FIGS. 12-13 , the connector  518  supports four electrical contacts  641 ,  642 ,  643  and  644 —ground, 5VDC-in, 24VDC-in and resistance-sense—that engage corresponding electrical contacts  71 ,  72 ,  73  and  74  ( FIG. 2 ) of the base  10 . A three-conductor electrical line  645  extends from the first three contacts  641 - 643  to the power head  172 . The line  645  conducts 5VDC and 24VDC from the base  20  to power the headlamp  524  and the brushroll motor  534 , respectively. The electrical power conducted to the headlamp  524  and the brushroll motor  534  can be manually interrupted with a power switch  646  located on the rigid tube  514  in front of the handgrip  540 . The connector  518  has a latch pin  646 , two hooks  648  and a prong  658  corresponding to those of the vacuuming head  12 . The connector  518  further has upper and lower sealing surfaces  660  and  662  to sealingly engage the upper and lower gaskets  49  ( FIG. 2 ) of the base  20 . 
     The connector  518  can be installed on the base  20  in a manner similar to that explained above for the vacuuming head  12 . Referring to  FIG. 14 , first the perch hooks  648  are mounted on the perch pins  60  of the base  20 . Then, the connector  518  is pivoted rearward (arrow  671 ) about the perch pins  60  until the latch pin  646  is captured by the latch  64  of the base  20 , thus bringing the connector  518  into an installed position shown in  FIG. 15 . 
     In the installation procedure shown in  FIG. 14 , the pivotal movement (arrow  671 ) of the connector  518  toward and into its installed position moves the contacts  641 - 644  of the connector  518  toward and into contact with the contacts  71 - 74  ( FIG. 2 ) of the base  20 , and moves the prong  658  ( FIG. 13 ) toward and into engagement with the sensor switch  76 , and moves the sealing surfaces  660  and  662  of the connector  518  into sealing engagement with the gaskets  49  of the base  20 . The base&#39;s perch pins  60  facilitate the installation procedure by supporting the weight of the connector  518  and by keeping components of the connector  518  properly aligned with mating components of the base  20  while the connector  518  is pivoted. 
     In its installed position shown in  FIG. 15 , the flexible tube  516  channels air into the upper inlet port  46  while the connector&#39;s sealing surface  662  covers and blocks the lower inlet ports  48 . The controller  100  ( FIG. 3 ) determines that the power head assembly  14  is installed by the resistance applied by the assembly  14  across the ground and resistance-sense contacts  71  and  74 . In response, the controller  100  disengages the clutch  98 , and thus disengages the drive pulley  90  from the motor  88 . 
     Referring to  FIG. 12 , pressing the main power switch  104  starts the fan motor  88  to drive the fan  80 . Pressing the power switch  646  at the handgrip  540  starts the power head motor  534  to drive the brushroll  530 . A user grasps the handgrip  540  to move the power head  510  about the floor  6 . The headlamp  524  illuminates the floor  6  in front of the power head  510 . The brushroll  530  rotates against the floor  6  to dislodge dirt. The dislodged dirt is carried by a flow of air from the floor  6  though the nozzle cavity  521 , the tubes  514  and  516 , the upper inlet port  46  ( FIG. 15 ), the fan  80  and the fill tube  87  ( FIG. 2 ) into the filter bag  24 . This route includes the flow path  399  that extends continuously rearward from the upper inlet port  46  to the impeller  87  and that frilly includes the first imaginary straight line L 1  extending from the inlet port to the impeller  87 . 
     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.