WO2004041053A1

WO2004041053A1 - Vacuum cleaner

Info

Publication number: WO2004041053A1
Application number: PCT/CA2003/001670
Authority: WO
Inventors: Wayne E. Conrad
Original assignee: Polar Light Limited
Priority date: 2002-11-06
Filing date: 2003-11-05
Publication date: 2004-05-21

Abstract

A surface cleaning head (12) for a vacuum cleaner has a bottom wall (28) having a dirty air inlet (34), a brushing member (32) associated with the dirty air inlet (34) and a dirt collection area (38) positioned downstream from the dirty air inlet (34) and configured to retain particulate material in the dirt collection area (38). The dirt collection area (38) has an upstream end and a downstream end, the downstream end having a smaller cross section than the dirty air inlet (34). The downstream end has an air outlet (46), which is in airflow communication with a source of suction, and at least one filtration member when the vacuum cleaner is in use.

Description

Title: VACUUM CLEANER

Field of the Invention

[0001] This application relates to vacuum cleaning appliances such as upright vacuum cleaners, stick vacuum cleaners, canister vacuum cleaners, central vacuum cleaners and the like. Background of the Invention

[0002] Various different formats of vacuum cleaners are known in the art. These include upright vacuum cleaners, canister vacuum cleaners, stick vacuum cleaners and central vacuum systems. An important characteristic of any type of vacuum cleaner is its ability to clean a surface. Typically, a vacuum cleaner uses a combination of mechanical action and suction to entrain material in an air stream that enters the vacuum cleaner and is then filtered in one or more filtration steps that are provided in the vacuum cleaner. The mechanical action is typically provided by a rotating brush, which is used to lift dirt from a surface (especially carpet or the like) so that the dirt may be entrained in an air stream, which is then drawn into the vacuum cleaner through a dirty air inlet provided in the base of a floor cleaning head. In order to improve the efficiency of a vacuum cleaner, it has been known to increase the airflow at the dirty air inlet. By increasing the airflow at the dirty air inlet, the ability of a vacuum cleaner to pick up larger debris by suction is enhanced.

[0003] Battery operated vacuum cleaners are also known in the art.

Battery operated vacuum cleaners utilize batteries that are provided on board the vacuum cleaner to power a suction motor and also a brush motor, if same is provided. In order to provide a battery operated vacuum cleaner with a level of suction similar to that of vacuum cleaners that are operated by household current or the like, and to thus have a cleaning efficiency that is similar to a conventionally powered vacuum cleaner, a relatively large number of batteries is required. The use of such a large number of batteries results in a substantial increase in the weight of the vacuum cleaner. The increased weight of the vacuum cleaner will tend to cause the vacuum cleaner to sink into a carpeted surface. In addition, it may be difficult for a consumer to push. Further, even with a large number of batteries, the vacuum cleaner may have an operating life that is too short for a commercially viable product. In addition, the use of a large number of batteries substantially increases the cost of the vacuum cleaner.

[0004] In order to reduce on board power capacity which is required

(e.g. to reduce the number of batteries which are used or enable cheaper batteries having a lower Amp hour rating to be used) without compromising performance or run time has proved difficult. Summary of the Invention

[0005] There is a relationship between the number of batteries that are utilized in the vacuum cleaner and the volume of airflow that travels through the vacuum cleaner (which may be measured in cubic feet per minute (cfm)). The higher the airflow rate, the higher the velocity of the air at the dirty air inlet. However, it has been determined by the inventor that the number of batteries which are required to increase the volume of air flow through a vacuum cleaner increases at least proportionally as the volume of air flow through a vacuum cleaner is increased. Further, when volume of airflow is above about 30 cfm, the number of batteries required to increase the volume of air traveling through the vacuum cleaner increases at a rate that is more than proportional to the increase volume of airflow produced by the additional batteries. Accordingly, if a vacuum cleaner were designed utilizing fewer batteries, then the efficiency of the vacuum cleaner would be reduced (due to a decrease in the cfm of airflow through the vacuum cleaner and, accordingly, a decrease in the velocity of the air at the dirty air inlet to the vacuum, cleaner).

[0006] In accordance with the instant invention, a new suction inlet construction for a vacuum cleaner has been developed. The construction includes a brushing member which is configured to direct particulate matter up a ramp and a particulate collection area positioned downstream of the ramp. The particulate collection area has a lower surface that is below the top of the ramp. The particulate collection area has a downstream exit, which is in flow communication with a downstream filter member. Accordingly, the particle collection area may function as a hopper to store heavier particulate matter.

[0007] In operation, a user may encounter a portion of the surface to be cleaned that has a large amount of particulate matter (e.g. a spill of rice). With the limited airflow which may be produced by a battery-powered suction motor, a battery-operated vacuum cleaner may be unable to clean up the spill, even in a few passes. However, in accordance with this aspect of the instant invention, the brushing member can be used to sweep the particulate matter up the ramp and into the particulate collection area. Thus, even in one pass, a battery-powered vacuum cleaner may pick up most, if not essentially all, of the particulate matter. The airflow through the vacuum cleaner may then slowly entrain the particulate matter in the particulate collection area. Preferably, the particulate collection area is shaped such that the airflow rate at the outlet from the particulate collection area is higher than at the ramp inlet. As the airflow rate increases, the dirty air stream traveling through the particulate collection area will be able to entrain additional particulate matter. For example the particulate collection area may be funnel shaped. Accordingly one or more of the walls, floor and roof of the particulate collection area may be narrowed towards the particulate collection area so as to reduce the cross-sectional area of the particulate collection area and therefore, increase the airflow rate therethrough.

[0008] Preferably, the outlet from the particulate collection area extends upwardly from the floor. Accordingly, the dirty air stream need not raise the particulate matter above a sill or other abutment member.

[0009] The novel suction inlets of the instant invention produce enhanced cleaning efficiency at lower power operating levels. Accordingly, a battery-operated vacuum cleaner having good cleaning efficiency (e.g., similar to upper end conventionally powered vacuum cleaners) and acceptable operating life on a single battery charge (e.g. up to 30 minutes or more) may be developed. For example, a vacuum cleaner utilizing the designs may have a suction motor, which requires only about 100 watts of power. Such a motor is substantially smaller and lighter than conventional vacuum cleaner motors (which are known to draw 10 - 15 amp). The lighter weight of the motor offsets, to a degree, the weight of the batteries thereby limiting the weight of the battery-operated vacuum cleaner. Further, due to the lower power requirement of the vacuum cleaner, fewer batteries are required so as to provide a battery operated vacuum cleaner with an acceptable operating life, thus also assisting in reducing the weight of the vacuum cleaner.

[0010] The new designs may be used advantageously with both a battery-operated vacuum cleaner as well as a vacuum cleaner that is operated from an external electrical source (e.g. by plugging the vacuum cleaner into a household, office or commercial electrical outlet).

[0011] If the vacuum cleaner is operated from an external power source, then the use of the inlet design is also advantageous. The use of a motor which draws a reduced amount of power will enable a vacuum cleaner to be manufactured which is lighter and, in addition, quieter.

[0012] In accordance with one embodiment of the instant invention there is provided a surface cleaning head for a vacuum cleaner comprising:

(a) a bottom wall having a dirty air inlet and a brushing member associated with the dirty air inlet; and,

(b) a dirt collection area positioned downstream from the dirty air inlet and configured to retain particulate material in the dirt collection area, the dirt collection area having an upstream end and a downstream end, the downstream end having a smaller cross section than the dirty air inlet, the downstream end having an air outlet which is in air flow communication with a source of suction and at least one filtration member when the vacuum cleaner is in use.

[0013] In one embodiment, the surface cleaning head has a ramp the extends upwardly from a first end proximal the dirty air inlet a second end proximal the dirt collection area and the dirt collection area has a bottom wall that is positioned below the second end of the ramp.

[0014] In another embodiment, the air outlet is positioned adjacent the bottom wall of the dirt collection area. [0015] In another embodiment, the dirt collection area has at least one wall which is configured to convey particulate material to the air outlet other than due solely to the air flow through the dirt collection area.

[0016] In another embodiment, the dirt collection area has at least one wall that is configured to covey particulate material to the air outlet under at least one of the force of gravity and vibrations produced when the vacuum cleaner is in operation.

[0017] In another embodiment, the dirt collection area has a bottom wall that is sloped downwardly towards the air outlet of the dirt collection area.

[0018] In another embodiment, the dirt collection area has a bottom wall that is sloped inwardly and downwardly towards the air outlet of the dirt collection area.

[0019] In another embodiment, the dirt collection area has a bottom wall that is sloped inwardly towards the air outlet of the dirt collection area.

[0020] In another embodiment, the dirt collection area is configured to accelerate the airflow passing through the dirt collection area.

[0021] In another embodiment, the velocity of the air entering the air outlet in the downstream end of the dirt collection area is at least about 5 times greater than the velocity of air when it enters the dirty air inlet.

[0022] In another embodiment, the velocity of the air entering the air outlet in the downstream end of the dirt collection area is at least about 10 times greater than the velocity of air when it enters the dirty air inlet.

[0023] In another embodiment, the cross sectional area of the dirt collection area generally continuously decreases from the upstream end of the dirt collection area to the downstream end of the dirt collection area. [0024] In another embodiment, the brushing member is a rotary brush.

[0025] In accordance with another embodiment of the instant invention there is also provided a surface cleaning head for a vacuum cleaner comprising: (a) a bottom wall having a dirty air inlet and a brushing member associated with the dirty air inlet; and,

(b) a dirt collection area having a bottom wall and positioned downstream from the dirty air inlet and configured to retain particulate material in the dirt collection area, the dirt collection area having an upstream end and a downstream end, the downstream end having an air outlet which extends upwardly from the bottom wall of the dirt collection area and is in air flow communication with a source of suction and at least one filtration member when the vacuum cleaner is in use. [0026] In one embodiment, the surface cleaning head has a ramp the extends upwardly from a first end proximal the dirty air inlet a second end proximal the dirt collection area and the bottom wall of the dirt collection area is positioned below the second end of the ramp.

[0027] In another embodiment, the dirt collection area has at least one wall which is configured to convey particulate material to the air outlet other than due solely to the air flow through the dirt collection area.

[0028] In another embodiment, the dirt collection area has at least one wall that is configured to covey particulate material to the air outlet under at least one of the force of gravity and vibrations produced when the vacuum cleaner is in operation.

[0029] In another embodiment, the bottom wall of the dirt collection area is sloped downwardly towards the air outlet of the dirt collection area. [0030] In another embodiment, the bottom wall of the dirt collection area is sloped inwardly and downwardly towards the air outlet of the dirt collection area.

[0031] In another embodiment, the bottom wall of the dirt collection area is sloped inwardly towards the air outlet of the dirt collection area.

[0032] In another embodiment, the dirt collection area is configured to accelerate the airflow passing through the dirt collection area.

[0033] In another embodiment, the velocity of the air entering the air outlet in the downstream end of the dirt collection area is at least about 5 times greater than the velocity of air when it enters the dirty air inlet.

[0034] In another embodiment, the velocity of the air entering the air outlet in the downstream end of the dirt collection area is at least about 10 times greater than the velocity of air when it enters the dirty air inlet.

[0035] In another embodiment, the cross sectional area of the dirt collection area generally continuously decreases from the upstream end of the dirt collection area to the downstream end of the dirt collection area.

[0036] In another embodiment, the brushing member is a rotary brush.

[0037] In another embodiment, the downstream end has a smaller cross section than the upstream end. [0038] In accordance with another embodiment of the instant invention there is also provided a method of cleaning a surface using a surface cleaning head having a dirty air inlet in fluid communication with a source of suction comprising:

(a) introducing a dirty air stream into the surface cleaning head through the dirty air inlet;

(b) passing the dirty air stream through a portion of the surface cleaning head which is configured to collect particulate matter which is introduced into the surface cleaning head through the dirty air inlet and which is not entrained in the dirty air stream as the particulate matter enters the dirty air inlet or which does not remain entrained in the dirty air stream;

(c) passing the dirty air stream through a portion of the surface cleaning head which is configured to increase the velocity of the dirty air stream;

(d) conveying the collected particulate matter to the position at which the velocity of the dirty air stream is increased; and,

(e) using the increased velocity of the dirt air stream to entrain at least some of the collected particulate matter. [0039] In one embodiment, the method further comprises the step of using mechanical action to draw particulate matter into the dirty air inlet.

[0040] In one embodiment, the method further comprises the step of sweeping particulate matter into the dirty air inlet.

[0041] In one embodiment, the method further comprises the step of using a rotating brush to at least assist in sweeping particulate matter into the dirty air inlet.

Brief Description of the Drawings

[0042] These and other advantages of the instant invention will be more fully and completely understood in accordance with the following description of the preferred embodiments of the vacuum cleaner in which:

[0043] Figure 1 is a perspective view of a vacuum cleaner according to the instant invention;

[0044] Figure 2 is a side view of the vacuum cleaner of Figure 1 ;

[0045] Figure 3 is a partial cut away view of the floor cleaning head of the vacuum of Figure 1 ;

[0046] Figure 4 is a cross section along the line 4 - 4 of Figure 8;

[0047] Figure 5 is a partial cut away of an alternate embodiment of the floor cleaning head of the vacuum cleaner of Figure 1; [0048] Figure 6 is a cross section along the line 4 - 4 in Figure 1 of the alternate embodiment of the floor cleaning head of Figure 5;

[0049] Figure 7 is a cross section along the line 7 - 7 in Figure 8;

[0050] Figure 8 is a top plan view of the preferred embodiment of the floor cleaning head shown in Figure 3 with the top cover removed;

[0051] Figure 9 is a schematic diagram showing one air flow path for the floor cleaning head of Figure 5 wherein the filtered air is recycled to the dirty air inlet for the rotatably mounted brush;

[0052] Figure 10 is a schematic drawing of the floor cleaning head of figure 9 wherein a valve is provided;

[0053] Figure 11 is a schematic front prospective view of the valve shown in Figure 10;

[0054] Figure 12 is a front view of the valve of Figure 10;

[0055] Figure 13 is a side view of the valve of Figure 10; [0056] Figures 14 - 16 show the operation of the valve of Figure 10;

[0057] Figure 17 is a cross section along the line 17 - 17 of the alternate embodiment of the floor cleaning head shown in Figure 19;

[0058] Figure 18 is a cross section along the line 17 - 17 of an alternate embodiment of the floor cleaning head shown in Figure 19; [0059] Figure 19 is a top plan view of an alternate embodiment of the floor cleaning head of Figure 1 with the top cover removed;

[0060] Figure 20 is a perspective view of a manually controllable brush speed button according to one embodiment of this invention;

[0061] Figure 21 is a top plan view of an alternate embodiment of a manually adjustable brush speed control according to another embodiment of this invention; [0062] Figure 22 is a schematic drawing of an acoustically controlled electronic brush speed adjustment system according to another embodiment of the instant invention;

[0063] Figure 23 is an alternate embodiment of a cross section along the line 17 - 17 of the alternate embodiment of a floor cleaning head shown in Figure 19;

[0064] Figure 24 is an alternate embodiment of a cyclone chamber for an inlet duct according to one embodiment of this invention; and,

[0065] Figure 25 is a further alternate embodiment of a cyclone chamber for an inlet duct according to an alternate embodiment of this invention.

Detailed Description of the Invention

[0066] The following description of the preferred embodiment is based on the upright vacuum cleaner 10 shown in Figures 1 and 2. It will be appreciated that the improvements in the vacuum cleaner design discussed herein may be applied to a floor cleaning head of an upright vacuum cleaner, a canister vacuum cleaner, a central vacuum system, or any other vacuum cleaner which is designed to clean debris from a floor. It will also be appreciated that the improvements herein may be utilized in vacuum cleaners utilizing any source of power (including batteries and household electrical current), although the use of an onboard power supply is preferred.

[0067] Referring to Figures 1 and 2, vacuum cleaner 10 has a floor cleaning head 12 and an upper body portion 14 pivotally mounted to floor cleaning head 12, as is known in the art. A handle 16 is provided, e.g., on upper body portion 14 so as to enable a consumer to move vacuum cleaner 10 over a surface to be cleaned, as is known in the art. Typically, one or more filtration members (such as a cyclone or a filter bag, but preferably at least one cyclone) may be incorporated into upper body portion 14. However, it will be appreciated that some or all of the filtration members may be provided in floor cleaning head 22 (see for example the embodiment shown in Figure 9). [0068] Generally, floor cleaning head 12 may be of any particular configuration. As shown in Figure 1, floor cleaning head 12 has front wheels 18 and rear wheels 20 to enable the vacuum cleaner to be able to be pushed over a surface to be cleaned. Floor cleaning head 12 also has a top wall 22, side walls 24, a front wall 26, a bottom wall 28 and rear wall 30. If vacuum cleaner 10 is battery operated, then the batteries may be provided in floor cleaning head 12. Alternately, the batteries could be provided, for example, in a battery pack, which is removably mounted to upper body portion 14. Floor cleaning head 12 may utilize glides or other means instead of wheels to enable the vacuum cleaner to be able to be pushed over a surface to be cleaned, as is known in the art.

[0069] Front wheels 18 are preferably provided adjacent side 24 of floor cleaning head 12 in front of rotatable brush 32 (see for example Figures 3, 7 and 8). As shown in these Figures, wheels 18 are rotatably mounted in a housing, which is provided in or adjacent front wall 26 of floor cleaning head 12. It will be appreciated that front wheels 18 may be provided at any location along the length of front wall 26. Preferably, wheels 18 are provided adjacent side walls 24 of floor cleaning head 12 so as not to roll over dirt that will be encountered by brush 32. Any other support means for a surface cleaning head, which is known in the art, may be used.

[0070] In the alternate embodiment shown in Figure 4, front wheels 18 are provided rearwardly of brush 32. An advantage of this embodiment is that the wheels will not engage the dirt on the surface prior to the dirt encountering brush 32 (provided that floor cleaning head 12 is moved forwardly, in the direction of arrow A in Figure 4). However, if wheels 18 are provided rearward of brush 32, they will tend to leave a track in the carpet. An advantage of positioning wheels 18 in front of brush 32, as shown for example in Figure 5, is that the brush will groom the carpet and remove the tracks left by wheels 18. [0071] In accordance with this invention, an improved suction inlet for a vacuum cleaner utilizes a ramp 36 and a funnel shaped dirt receiving area 38. For example, referring to Figures 3, 4 and 8, floor cleaning head 12 has brush 32 mounted above dirty air inlet 34. Ramp 36 is positioned rearward of brush 32. Dirt receiving area 38 is positioned rearward of ramp 36 and has sidewalls 40, bottom wall 42 and rear wall 44. An air outlet port 46 is provided in rear wall 44. Air outlet port is in fluid flow communication with a suction motor, which may be provided, for example, in upper body portion 14 of vacuum cleaner 10 or at any other location known in the vacuum cleaner art. It will be appreciated that the suction motor may be a dirty air motor or a clean air motor as is known in the art. It will also be appreciated that brush 32 may be any brush or agitation means known in the vacuum cleaner art.

[0072] Ramp 36 comprises an inclined surface having a lower end 48 and an upper end 50. As shown in Figure 4, ramp 36 is a planar surface having a constant angle of inclination. Rear wall 52 of ramp 36 extends downwardly to bottom wall 42 of receiving area 38. As shown in Figure 4, rear wall 52 extends generally vertically.

[0073] As floor cleaning head 12 travels over surface 92 the action of brush and/or the air flow into inlet 34 produced by the suction motor of the vacuum cleaner will cause dirt to enter floor cleaning head 12 via dirty air inlet 34 and to travel upwardly along or above ramp 36 into dirt receiving area 38. Brush 32 may provide a sweeping action to sweep larger and heavier particulate matter up ramp 36 and past top 50 into dirt receiving area 38. Preferably brush is a rotatably mounted brush, however, brush 32 may operate in any manner that produces a sweeping action. Ramp 36 and dirt receiving area 38 may be configured in any manner provided that dirt receiving area has a bottom wall 42 that is positioned below top 50 of ramp 56. By shaping dirt receiving area 38 in this way, dirt can not travel forwardly through floor cleaning head 12 so as to exit dirty air inlet 34. In effect, dirt receiving area 38 comprises a hopper for receiving dirt that is picked up through dirty air inlet 34. Accordingly, ramp 34 need not be inclined as steeply as shown in Figure 4 and, in an alternate embodiment, it could be generally horizontal provided that bottom wall 42 is vertically displaced downwardly from the distal end of ramp 36 from brush 34 (i.e. top 50). It will be appreciated by those skilled in the art that the greater the vertical displacement between top 50 of ramp 36 and bottom wall 42 of receiving area 38, the greater the storage volume of receiving area 38. It will also be appreciated that rear wall 52 need not be vertical but may be inclined in any particular direction. For example, as shown in Figure 6, rear wall 52 may have a first section 56 which is inclined frontwardly towards front wall 26 of floor cleaning head 12 and a second portion which extends downwardly (and is curved) to bottom wail 42 of dirt receiving area 38. [0074] If wheels are mounted rearward of brush 32, then, as shown in

Figure 3, the bottom potion of ramp 36 may be provided with a recess 60 for receiving front wheels 18.

[0075] A surface that is to be cleaned typically has finer particulate matter (e.g. dust) as well as larger particles such as sand, rice or small stones that are to be removed by the vacuum cleaner. In a typical vacuum cleaner, a rotating brush will be able to lift such heavy particulate matter off of the surface to be cleaned. However, a relatively high velocity air stream is required to entrain such heavy particulate matter and transport it to the filter media. Accordingly, in order to have good cleaning performance, known vacuum cleaners require high volume of airflow so as to entrain such large particulate matter. In accordance with the instant invention, dirt receiving area 38 is a trough shaped member for accumulating material prior to the material being fed with the air stream to the filtration member. If an area of heavy dirt concentration is encountered, the airflow may not be sufficient to entrain all of the dirt. By providing a storage area, the excess material, which is not entrained, may be stored for entrainment in the air stream once the concentration of material being entrained in air stream decreases. Referring to Figure 4, if brush 32 encounters such heavy particulate matter, which cannot be entrained in an air stream, the particulate matter will be swept up or along ramp 36 and deposited in receiving area 38. [0076] In accordance with one embodiment of this invention, dirt receiving area 38 is funnel shaped. For example, referring to Figure 8, the length of rear wall 52 of ramp 36 (which is the front wall of dirt receiving area 38) is substantially longer than rear wall 44 of dirt receiving area 38 adjacent air outlet port 46. In addition, as shown in Figure 3, bottom wall 42 is sloped inwardly towards the central portion of bottom wall 42 adjacent air outlet port 46 as indicated by arrow B. Further, as shown in Figure 3, bottom wall 42 is sloped rearwardly towards air outlet port 46 as indicated by arrow C. Accordingly, if heavy particulate matter is swept into dirt receiving are 38, it will be conveyed by gravity and/or the vibration of the vacuum cleaner 10 towards outlet port 46, depending upon the entry point of such dirt into dirt receiving area 38. It will be appreciated that dirt receiving area 38 may be of any particular configuration which will convey the particulate matter by other than air flow alone to air outlet port 46. [0077] As will be appreciated, the cross sectional area of air outlet port

46 is substantially smaller than the cross-sectional area of dirty air inlet 34. Further, the rear most section 54 of dirt receiving area 38 has a cross section area that is also substantially reduced from that of 34. As the cross section area decreases, and the velocity of the airflow will increase provided that the volume of air traveling through floor cleaning head 12 (e.g. as measured in cfm) remains constant. Accordingly, the velocity of the air as it approaches air outlet port 46, particularly in the vicinity of rear most section 54, may be substantially increased compared to its velocity at dirty air inlet 34 allowing the air to entrain heavy particulate matter which accumulates in dirt receiving area 38.

[0078] Depending upon the configuration of dirty air inlet 34 and receiving area 38, the velocity of air at rear most section 54 may be five or ten times greater than the velocity of the air at dirty air inlet 34. It will be appreciated that the actual change in velocity will vary depending upon the size of dirty air inlet 34 and the configuration of dirt receiving area 38. It will also be appreciated that the configuration of dirt receiving area 38 may be changed to more greatly assist heavy particulate matter to travel towards outlet port 46 due to mechanical action (such as by increasing the steepness of floor 42). It will also be appreciated that bottom wall 42 need not be sloped transversely inwardly in the direction of arrow B. For example, if a plurality of inlet ports 46 were positioned along the transverse length of rear wall 44, or if a single outlet port 46 were provided along a substantial portion of the length of rear wall 44 wherein inlet port 46 had a substantially reduced vertical height, then bottom wall 44 may need to be only sloped rearwardly towards inlet 46. Overall, the exact configuration that is selected will vary depending upon the desired velocity at outlet 46. Preferably, dirt receiving area 38 and outlet 46 are constructed so as to provide a five fold increase in the velocity of the air in the portion of dirt receiving area 38 adjacent outlet 46 (i.e. rearmost section 54) and, more preferably at least about a 10 fold increase in velocity.

[0079] As shown in Figure 3, outlet 46 is preferably positioned adjacent bottom wall 42. It will be appreciated that outlet 46 may be positioned above outlet 42. However, in such a case, a ramp or other means may be needed to permit dirt to flow upwardly into outlet 46. In the preferred embodiment, outlet 46 is positioned adjacent or essentially adjacent bottom wall 42. The suction motor is preferably positioned downstream from outlet 46, although it may be positioned upstream from outlet 46.

[0080] By using a funnel shaped collection area, the volume of air traveling through the vacuum cleaner may be substantially reduced without deleteriously affecting the efficiency of the vacuum cleaner in terms of its ability to pick up small heavy particulate matter. This arises due to the increase in the velocity of the air as the air travels though floor cleaning head 12 towards outlet 46. Accordingly, the wattage required by a suction motor for a vacuum cleaner may be substantially reduced since the increased velocity may be obtained merely by reconfiguring airflow passage 112 through floor cleaning head 12. Accordingly, the number of batteries which are required to operate a battery operated vacuum cleaner may be reduced so as to obtain a light weight, battery-operated vacuum cleaner having an operating life of, for example, thirty minutes or more, wherein the vacuum cleaner has good cleaning efficiency for small, heavy particulate matter. Alternately, if the volume of air traveling through the vacuum cleaner is not reduced, then the velocity of the air at outlet 46 may be enhanced thereby improving the efficiency of the vacuum cleaner.

[0081] Optionally brush 32 may be rotated at different speeds depending upon the type and amount of material that enters floor cleaning head 12 via dirty air inlet 34. In accordance with this aspect of the invention, a slower brush speed is preferably utilized to pick up heavier particulate matter whereas a faster speed is preferably utilized to pick up finer particulate matter. A faster rush speed beneficially picks up and assists in entraining into an air flow stream fine particulate matter (e.g. dust and the like). The brush speed to entrain finer particulate matter may be from about 3,000 to about 10,000, preferably from about 4,000 to about 7,500 and more preferably from about 4,000 to about 6,000 rpm. Heavier particulate matter (e.g. sand, small stones, rice or larger particulate matter having a moderate density) is preferably picked up using a slower speed of brush 34. To pick up such material, brush 34 preferably rotates at a speed of about 500 to about 3,000 rpm and, preferably from about 1 ,000 to about 2,000 rpm. If a higher speed is utilized to collect large heavier particulate matter, then at least some of the heavier particulate matter would be traveling at a higher velocity as it enters dirty air inlet 34. This can result in the material encountering a wall surrounding brush 32 and being deflected back out from the interior of floor cleaning head 12 to the surface being cleaned. [0082] The speed of the brush may be controlled in a variety of manners. For example, the speed may be manually controlled by a consumer pushing a button that may be located anywhere on the vacuum cleaner. For example, referring to Figure 1 , brush speed control button 64 is positioned adjacent main on/off button 62 on top surface 66 of upper body portion 14. It will also be appreciated that button 64 may be a foot pedal or the like. When vacuum cleaner 10 is operated (e.g. a consumer pushes button 62) then the brush may commence rotating at a preset speed (e.g. a higher speed for collecting finer particulate matter). If a user notices that there is heavier particulate matter that the vacuum cleaner has to pick up, then the consumer may depress button 64 to reduce the speed of rotation of brush 34. It will also be appreciated that vacuum cleaner 10 may be designed so as to commence brush 34 rotating at the slower speed when vacuum cleaner 10 is turned on and that a consumer depresses button 64 to accelerate the speed of rotation of brush 34.

[0083] It will be appreciated that button 64 may be configured so as to adjust the speed of brush 34 between a series of discrete speeds or, alternately, to be able to adjust the speed of brush 34 between two preset speeds at any of an infinite number of speeds. For example, referring to Figure 20, a rotary button 68 may be moved between a plurality of discrete positions indicated by speed markings 70 using alignment indicator 72 to select a desired position. Alternately, as shown in Figure 21 , a slide control knob 74 may travel along slot 76 and be set in an infinite number of positions between the opposed ends 78 of slot 76. In either event, the speed of brush 34 could be varied by adjusting the power delivered to brush motor 84, which is drivingly connected to brush 34, based upon the position of rotary button 68 or slide control knob 74 (e.g., these controls could be drivingly connected to a variable rheostat). Alternately, if a foot operated pedal is utilized, then a clutch and transmission mechanism could be utilized to adjust the speed of brush 34 (e.g., by changing a drive belt that engages brush 34 from one size of pulley to another size of pulley). [0084] Preferably, the speed of brush 34 is adjusted based upon the sound of particulate matter as it travels through floor cleaning head 12. In particular, larger dirt particles such as stones and rice will tend to "ping" or "knock" as they enter and travel through the housing surrounding brush 34. Accordingly, an acoustic sensor could be provided for varying the power provided to brush motor 84 based on the noise produced by the particulate matter traveling through floor cleaning head 12. For example, referring to Figure 4, an acoustic sensor could be provided along inner surface 80 of top wall 22 or front wall 26 surrounding brush 32. Alternately, as such "pinging" or "knocking" is relatively loud, the acoustic sensor need not be positioned immediately adjacent brush 34. For example, an acoustic sensor 82 could be provided in dirt receiving area 38 (see Figure 3) or, alternately, it may be placed elsewhere in vacuum cleaner 10 provided that it is located sufficiently close to brush 34 to be able to detect the sound produced by the larger dirt particles.

[0085] Acoustic sensor 82 may be connected to brush motor 84 such as via controller 86 (see Figure 22). In operation, acoustic sensor 82 detects a noise level, preferably in the vicinity of brush 34. Acoustic sensor 82 produces an electrical signal that is transmitted by a wire 88 to controller 86. Controller 86 produces a signal that adjusts the speed of brush motor 84 based upon the signal received from acoustic sensor 82. For example, controller 86 may increase or decrease the power that is delivered to brush motor 84 via wire 88 based upon a pre-programmed algorithm that is provided with controller 86. Thus, as the intensity of the signal that is detected by acoustic sensor 82 increases, the power delivered to brush motor 84, such as by wire 90, may be decreased. It will be appreciated that controller 86 may adjust the speed of brush motor 84 between two preset levels, a number of preset levels or an infinite number of levels, depending upon the algorithm programmed into controller 86. It will also be appreciated that brush motor 84 may be drivingly connected to brush 34 by any means known in the art such as a direct drive system or a belt driven system. [0086] In accordance to another embodiment of the instant invention, front wall 26 of floor cleaning head 12 may have a recess 94 removed therefrom at a position adjacent the surface being cleaned so as to prevent particulate matter being embedded into carpet as floor cleaning head 12 passes over the carpet or, alternately, from pushing dirt ahead of floor cleaning head 12. In particular, in known designs, the front wall of a vacuum cleaner extends down to cover the vertical front face of the housing of the rotatable brush. As the vacuum cleaner travels across a floor, the front of the vacuum cleaner may engage dirt. Depending upon a number of factors including the weight of the vacuum cleaner and the amount of dirt, some of the dirt may be pushed downwardly and embedded into the carpet by the passage of the front wall of the floor cleaning head over the dirt. This can result in a decrease in the efficiency of the vacuum cleaner since not all of the embedded dirt may be removed by the action of the suction produced by the vacuum cleaner and a rotatable brush. In another scenario, a user may have spilled a quantity of material (e.g. sugar, rice or the like) on a surface to be cleaned. In such a case, the front wall of a vacuum cleaner may push the dirt ahead of the vacuum cleaner instead of permitting the dirt to travel underneath the floor cleaning head to the dirty air inlet. If recess 94 is provided, then the large quantity of particulate matter may be swept up ramp 36 in dirt receiving area 38 in one or only a few passes and the air stream may then slowly entrain the particulate matter in dirt receiving area 38 as the vacuum cleaner is used to clean different areas of a surface.

[0087] In accordance with this preferred embodiment of the instant invention, front wall 26 of floor cleaning head 12 has a recess 94 provided in it so as to permit dirt to travel into or underneath floor cleaning head 12 without being embedded into carpet or being pushed in front of floor cleaning head 12. Referring to Figures 1 , 3 - 7, 9, 10, 17, 18 and 23, recess 94 is provided in front wall 26. Side walls 96 and bottom surface 98 of front wall 26 define recess 94. The vertical height H of recess 94 (which is shown in Figure 7 as the vertical distance between bottom surface 98 and surface 92 which is to be cleaned) may be about one half to about two thirds of the length of a bristle of brush 32. For a typical brush, height H may be about 1/4 to about 1/2 of an inch. However, it will be appreciated that height H may be greater than this amount.

[0088] Generally, front wall 26 prevents a consumer or furniture form contacting brush 32 as it rotates. Accordingly, if the height of recess 94 is increased too much, brush 94 may scrape a consumer or furniture as a consumer vacuums with floor cleaning head 12. Generally, the upper limit of height H may be selected based upon the degree to which brush 32 is to be enclosed so as to prevent a consumer or other object from encountering brush 32. In one variation, the upper level of bottom surface 98 may be set so that angle A is 90° or less, wherein angle A, as shown in Figure 7, defines the angle between the vertical and a line extending forwardly from the center of brush 32 to surface 98.

[0089] In order to reinforce front wall 96, one or more support members

100 (see Figure 5) may be provided. Support members 100 or the like may be provided if needed to prevent front wall 26 deflecting too much during the operation of the vacuum cleaner. Front wall 26 may be reinforced by other means such as using a stiffer material of a thicker material.

[0090] If floor cleaning head 12 is provided with a recess 94, then, preferably, a deflector 102 is provided. Deflector 102 may comprises a member that extends inwardly from inner wall 80 of front surface 26, preferably adjacent bottom 98 of front wall 26. If recess 94 is provided or a ramp 36 is provided, then brush 32 preferably rotates counter clockwise. Thus, some of the particulate matter may also be caused to travel counter clockwise. With the provision of recess 94, some of this particulate matter could exit floor cleaning head 12 via recess 94 and be deposited in front of the vacuum cleaner. While the continued operation of floor cleaning head 12 will result in such particulate matter being picked up again, the appearance of particulate matter exiting floor cleaning head 12 is undesirable from a consumer appearance point of view. Accordingly, deflector 102 is preferably provided.

[0091] Deflector 102 is positioned and configured so as to prevent such particulate matter from traveling out of floor cleaning head 12 via recess 94. Accordingly, as shown, for example, in Figure 4, deflector 102 may be a thin planner member that extends along the length of recess 94 and extends rearwardly (i.e. inwardly towards brush 32) a sufficient extent so as to prevent, or essentially prevent, dirt from traveling outwardly between rearward end 104 of deflector 102 and outward end 106 of bristles 108. Preferably, rearward end 104 terminates sufficiently short of outward end 106 of bristles 108 so that bristles 108 do not encounter deflector 102 during normal operation. However, the gap between ends 104 and 106 is preferably sufficiently small so as to prevent or substantially limit the outward transport of dirt through recess 94. It will be appreciated by those skilled in the art that deflector 102 need not be positioned on bottom 98 of front wall 26. Deflector 102 may be positioned on inner surface 80 at a position spaced upwardly from bottom 98. In addition, deflector 102 need not be rectangular in shape but may be of any particular cross section that has sufficient rigidity. In addition, deflector could be angled upwardly or downwardly.

[0092] Upper surface 110 of air flow passage way 112 is preferably configured so that particulate matter which encounters upper surface 110 is deflected into dirt receiving area 38. In particular, as dirt enters air inlet 34, it will travel rearwardly and upwardly in the direction of ramp 36. Heavier particulate matter may not be re-directed by the air stream traveling through passage 112 and/or gravity so as to be deposited into dirt receiving area 38. For example, some of the heavier particles could continue to travel upwardly and hit upper surface 110. This particulate matter may deflect off of inner surface 110 of passage 112 and be directed out of inlet 34. Accordingly, inner surface 110 is preferably shaped so as to act as a deflector to direct particulate matter that engages surface 110 into dirt receiving area 38. Inner surface 110 may be of any particular configuration that will perform this function. The exact configuration will depend, inter alia, upon the configuration of ramp 36 as well as of dirt receiving area 38. For example, inner surface 110 could be radiused or, as shown in Figure 4, it could be a generally planner surface. Preferably, inner surface 110 is angled upwardly and rearwardly from the horizontal. As shown in Figure 4, for example, inner surface 110 may be angled upwardly by an angle B from the horizontal. Angle B may vary from 5 to 35°, more preferably from about 5 to about 15° and, most preferably is about 10°. [0093] Optionally, a floor cleaning head 12 includes a first dirty air inlet

34 associated with rotating brush 34 (i.e. a brush inlet) and a second suction let 114. Brush inlet 34 is provided for picking up larger or heavier particulate matter which may be deposited on surface 94 which is to be cleaned. Suction inlet 114 is configured to have a higher velocity of air at inlet 114 then inlet 34. Accordingly, as shown in, for example, Figure 6, inlet 114 is substantially smaller than inlet 34 thereby substantially increasing the velocity of the air entering inlet 114 as compared to the velocity of the air entering inlet 34. Preferably, the velocity of the air entering inlet 114 is at least five times the velocity of the air entering inlet 34, more preferably, the velocity of the air entering inlet 114 is at least ten times the velocity of the air entering inlet 34 and, more preferably, the velocity of the air entering inlet 114 is from ten to one hundred times the velocity of the air entering inlet 34. In order to achieve these differences in velocity, the amount of air drawn through inlets 114 and 34 may be varied and the cross section area of the air flow ducts downstream from inlets 114 and 34 (e.g., ducts 116 and 112) may be varied.

[0094] In accordance with such an embodiment as shown in Figure 7, airflow passage 112 is provided downstream from inlet 34. Similarly, airflow passage 116 is provided downstream from inlet 114. Inlets 112 and 116 air in air flow communication with one or more filter members, preferably the same filter members. Accordingly, airflow passages 114 and 116 may be combined in advance of the filter members. As shown in Figure 7, ducts 112 and 116 merge downstream of outlet 46 to form a single main duct 118 that is in air flow communication with one or more filter members and a suction motor. By varying the cross-section area of duct 116 and 118, the amount of air traveling through each may be adjusted and thus the velocity of the air traveling through the inlet 114 and inlet 34 will be varied. In one particular embodiment, preferably about 50% of the air travels through passage 112 and about 50% of the air travels through passage 116. By varying the cross-section area of inlets 114 and 34, the velocity of the air traveling through the inlet 114 and inlet 34 may also be varied. It will be appreciated that a person skilled in the art may obtain a desired air velocity at each of inlets 34 and 114 by varying these parameters and adjusting the volume of air drawn by the suction motor.

[0095] Inlet 114 may be provided in front of, to the rear of, or both in front of and to the rear of, inlet 34. For example, as shown in Figure 5, inlet 114 is preferably provided rearward of inlet 34. Accordingly, larger particulate matter will be picked up by inlet 34 thus preventing inlet 114 from encountering larger particulate matter that could become wedged in inlet 114. In an alternate embodiment, it will be appreciated that inlet 114 could be provided in front of inlet 34 (see for example Figure 18). Alternately, two or more inlets 114 could be provided. For example, as shown in Figure 17, one inlet 114 could be provided in front of inlet 34and a second inlet 114 could be provided rearward of inlet 34. If an inlet 114 is provided in advance of inlet 34, an inlet 114 is preferably sized so as to not become blocked by larger particulate matter that will typically be encountered by floor cleaning head 12. [0096] Inlet 114 may be of any particular length. Preferably, as shown in Figure 19, the length of inlet 114 (i.e. in the direction of the width of floor cleaning head 12) is the same or essentially the same as the length of inlet 34. In addition, it is preferred that each of inlet 34 and inlet 114 extends essentially across the entirety of the width of floor cleaning head 12. It will be appreciated by those skilled in the art that if inlet 114 is shorter in length then the width of floor cleaning head 12, then not all of the surface over which floor cleaning head 12 passes will be cleaned by inlet 114.

[0097] Inlet 114 preferably has a width W (see Figure 6) that varies from about 1/32 to about 1/2 of an inch, preferably from about 1/16 to about 1/4 of an inch and, most preferably from about 1/8 of an inch to about 3/16 of an inch.

[0098] As shown in Figure 23, inlet 114 may be directly in air flow communication with passage 116. Accordingly, inlet 114 essentially comprises an extension of passage 116 (i.e. the height H of passage 116 is essentially the same width W of slot 114 as shown in Figure 23). [0099] In an alternate preferred embodiment, inlet 114 directs air into a cyclone chamber 120 having an inner wall 122 (see for example Figures 5 -7). Passage 116 communicates with cyclone chamber 112 via an inlet provided in inner wall 122. An enlarged view of cyclone chamber 120 is shown in Figures 24 and 25.

[00100] An advantage to using a cyclone downstream from inlet 114 is that it reduces the tendency of dirt to be ejected from inlet 114. In particular, as air enters inlet 114, it is induced to travel in a cyclonic pattern (see for example Figure 24) due to the configuration of inlet 114 and/or cyclone wall 122. Preferably, cyclone chamber is adjacent inlet 114. It is to be appreciated that cyclone chamber 120 is not a filtration member of the vacuum cleaner and is in fact positioned upstream from the filtration member or members of the vacuum cleaner.

[00101] Since the air travels in a swirling or cyclonic pattern in chamber 120, particulate matter that is contained in the air stream will be maintained in the air stream and conveyed into passage 116. Preferably, chamber 120 has a diameter which is at least three times the width W of inlet 114, more preferably at least four times, even more preferably at leas six times and most preferably at least about eight times or more the width W of inlet 114. It will be appreciated by those skilled in the cyclonic art that chamber 120 need not be circular in cross section, as shown in Figure 24, but may be square, triangular or any other cross sectional shape which is known in the cyclone art. If cyclone chamber 120 is not circular in cross section, then the diameter of the chamber is the mean effective diameter of a circle having the same area as the cross sectional area of the cyclone.

[00102] Optionally, a suction inlet for a vacuum cleaner, carpet extractor or the like may also utilize a narrow slot 114 which enters into a cyclone chamber 120 wherein the appliance does not include an inlet duct with a brush. [00103] In any of the foregoing embodiments, inlet 114 may have a brush associated therewith. For example, in the embodiment of Figures 5 - 7, inlet 114 is not provided with a brush. In the embodiment of Figure 24, brush 124 is provided on the rearward end of slot 114. In the alternate embodiment of Figure 25, brush 124 is mounted centrally in inlet 114 and may be supported by any means known in the art, such as a plurality of tie rods 116 which are provided at intermittent locations along the length of cyclone chamber 120. Tie rods 126 or other supporting members are configured so as not to deleteriously interfere with the cyclonic action in cyclone chamber 120.

[00104] If inlet 114 is positioned in front of brush 32, such as in the embodiment shown in Figure 17, then inlet 114 is preferably mounted so as to deflect or pivot upwardly away from surface 92 as floor cleaning head 12 moves forwardly and to pivot or deflect downwardly as floor cleaning head 12 moves rearwardly. Due to the fact that inlet 114 is relatively narrow, and is generally designed for collecting finer particulate matter, in accordance with this embodiment of the invention, inlet 114 is raised a sufficient distance above surface 92 as floor cleaning head 12 moves forwardly so as not to pick up larger particulate material which may damage inlet 114. Thus, the larger particulate matter will encounter brush 32 and will be picked up via inlet 34. On the rearward stroke of the vacuum cleaner (i.e. when floor cleaning head 12 is moved rearwardly), most or essentially all of the larger particulate matter should have been picked up by brush 32. Accordingly, inlet 114 may be lowered to a position sufficiently proximate to surface 92 so that it may vacuum finer particulate matter from surface 92.

[00105] The embodiment of Figure 9- demonstrates the use of these features in a vacuum cleaner wherein at least one filter member is provided in floor cleaning head 12. In addition, in this embodiment, an airflow system is illustrated wherein some, and preferably all, of the filtered air is recycled to inlet 34 to assist in entraining particulate matter in inlet 34. A floor cleaning head according to any of the embodiments herein may have one or more filter members in floor cleaning head 12 and/or may recirculate some or all of the treated air. [00106] As discussed previously, the vacuum cleaner may utilize any filtration step or steps known in the vacuum cleaner art. As shown in Figure 9, main airflow passage 118 preferably communicates with cyclone 128. The air is treated in cyclone chamber 128 and travels to optional first and second additional filtration steps 130 and 132. The additional filtration steps may be one or more of electrostatic precipitation, a filtration media or one or more additional cyclonic treatment steps. Some or all of the filtered air exiting optional additional filtration step 132 is preferably fed according to one embodiment via return air flow passage 134 to inlet 34. The air exits return airflow passage 134 at distal end 136. If a recess 94 is not provided, then the air may exit adjacent bottom wall 28.

[00107] In a vacuum cleaner that utilizes both an inlet 34 and an inlet

114, a valve may be provided to selectively close either of inlets 34 and 114 and, most preferably, to selectively close inlet 34. Generally, when a vacuum cleaner is used to clean a bare floor (e.g. linoleum, tile, wood or the like), a rotatable brush 32 is not required. In such cases, vacuum cleaners have been designed with means to stop brush 32 from rotating when a bare floor is being cleaned or means to raise brush 32 sufficiently above the surface which is being cleaned so as not to damage the surface in the bare floor cleaning mode. Any of these mechanisms may be utilized in any of the embodiments of this invention. If a floor cleaning head 12 has a brush inlet 34 and a suction inlet 114, then brush inlet 34 need not be used when floor cleaning head 12 is used to clean a bare floor. In such a case, airflow passage 112 may be closed by means of a valve, such as a valve that closes outlet 46. It will be appreciated that the valve may be positioned in any part of passage 112 upstream of the position that passage 112 merges with main passage 118. Outlet 46 may be closed by means of a valve that is manually actuated by a user or by any other means known in the vacuum cleaner art. By closing off air flow passage 112, all of the air flow into floor cleaning head 12 will travel through inlet 114 thus further increasing the velocity of the air entering 114. This increase in velocity is beneficial when cleaning a bare floor. [00108] In accordance with a further embodiment of the instant invention, airflow passage 112 may be closed by means of a valve when floor cleaning head 12 travels in one particular direction, preferably rearwardly. During the rearward stroke of floor cleaning head 12 (i.e. floor cleaning head 12 travels in the rearward direction), inlet 114 precedes inlet 34. Further, during a forward stroke, all or substantially all of the larger particulate matter may have been collected through inlet 34. Accordingly, by closing passage 112, enhanced suction may be produced through inlet 114 thereby increasing the efficiency of inlet 114 to pick up finer particulate matter that was not collected during the forward pass of floor cleaning head 12. An example of a mechanism to automatically close outlet 46 with each rearward passage of floor cleaning head 12 is shown in Figures 10 - 16.

[00109] As shown herein, valve 140 is provided downstream of outlet 46 and is sized so as to prevent air traveling through outlet 146 to passage 118. It will be appreciated that valve 140 may be positioned in front of outlet 46. Alternately, it will be appreciated that valve 140 may only close a portion of outlet 46 or the passage upstream or downstream thereof. In such a case, the amount of air traveling through passage 112 would be reduced but not eliminated. Valve 140 may extend upwardly through a slot in the upper surface of the airflow passage downstream from outlet 46 and is mounted to top arm 140. Top arm 140 has side arms 142 that extend downwardly therefrom through openings 146 in bottom wall 28 to brushes 144. Top arm 140 is pivotally mounted, such as by means of bearings 148, which may be, for example, mounted to the upper surface of the air flow passage downstream from outlet 46.

[00110] In operation, when floor cleaning head 12 travels forwardly, brushes 114 engage the surface 92 and therefore cause valve 138 to pivot rearwardly thereby opening outlet 46 (see Figure 14). As floor cleaning head 12 travels rearwardly, brushes 144 move forwardly in openings 146 due to engagement of brushes 144 and the surface 92 that is being cleaned. The forward movement of arms 142 relative to openings 146 causes valve 148 to rotate towards outlet 46 (see Figure 15). Further rearward motion of floor cleaning head 12 will cause arms 142 to continue to move forward with respect to opening 146 to the position shown in figure 16. At this position, outlet 46 has been closed by valve 128 pivoting to block the airflow passage downstream from outlet 46.

[00111] Accordingly, during the forward motion of the floor cleaning head 12, dirty air travels inwardly through both inlets 34 and 114. During the rearward travel of floor cleaning head 12, outlet 46 is closed thereby increasing the volume of air traveling through inlet 114 while terminating the flow of air through inlet 34. Accordingly, on the rearward stroke of the floor cleaning head 12, the fine dirt pick up which is achieved by inlet 114 is enhanced.

[00112] It will be appreciated by those skilled in the art that any one or more of the embodiments disclosed herein may be combined with any other embodiment disclosed herein. For example, in one such combined embodiment, a floor cleaning head 12 having a ramp 36 and a dirt receiving area 38 may utilize a brush having a variable speed to collect finer particulate matter and heavier particulate matter wherein the system may be controlled by an acoustic sensor. Such a vacuum cleaner may be provided with recess 94. Alternately, any embodiment of the vacuum cleaner which includes a dirt receiving area 38 downstream from a ramp 38 may include an inner surface of the top cover of air flow passage 112 which acts as the deflector to deflect particulate matter into dirt receiving area 38.

[00113] Any of the embodiments of a vacuum cleaner disclosed herein, may have a narrow slot 114 which preferably has a cyclone chamber 120 provided downstream thereof and, most preferably, immediately downstream thereof such that inlet 114 forms the inlet to cyclone chamber 120 and, optional a tangential inlet into cyclone chamber 120. In a particularly preferred embodiment, a vacuum cleaner includes a recess 94 and an inlet 114, with or without a cyclone chamber 120. By providing recess 94, the cross sectional area of inlet 34 is enlarged thereby further reducing the velocity of air entering inlet 34 (assuming the same volume of air flow is utilized by the vacuum cleaner). The further reduction in the velocity of the air at inlet 34 further decreases the efficiency of inlet 34 to collect finer particulate matter. The narrowing of the dirt receiving area will assist in transporting the larger particulate matter to the filter member. Accordingly, in such a case, it is particularly preferred to provide an inlet 114 either in front of and/or to the rear of brush 32 and, preferably, to the rear of brush 32, for collecting finer particulate matter.

[00114] Any embodiment, which utilizes a dirt collection area 38 and a suction inlet 114, may utilize a valve 140 so as to increase the velocity of air entering suction inlet 114. The valve may be closed either selectively by a consumer (e.g. for a bare floor cleaning mode) and/or, on the forward or rearward and, preferably, on the rearward stroke of floor cleaning head 12 so as to enhance the fine particulate collection during one of the strokes, and preferably, the rearward stoke, of floor cleaning head 12.

[00115] It will also be appreciated that the constructions may be used in association with a cleaner head for use in cleaning surfaces other than floors and as such may be referred to as a surface cleaner head.

[00116] These and other embodiments of the invention are within the scope of the following claims.

Claims

Claims:

1. A surface cleaning head for a vacuum cleaner comprising: a) a bottom wall having a dirty air inlet and a brushing member associated with the dirty air inlet; and, b) a dirt collection area positioned downstream from the dirty air inlet and configured to retain particulate material in the dirt collection area, the dirt collection area having an upstream end and a downstream end, the downstream end having a smaller cross section than the dirty air inlet, the downstream end having an air outlet which is in air flow communication with a source of suction and at least one filtration member when the vacuum cleaner is in use.

2. The surface cleaning head of claim 1 wherein the surface cleaning head has a ramp the extends upwardly from a first end proximal the dirty air inlet a second end proximal the dirt collection area and the dirt collection area has a bottom wall that is positioned below the second end of the ramp.

3. The surface cleaning head of claim 1 wherein the air outlet is positioned adjacent the bottom wall of the dirt collection area.

4. The surface cleaning head of claim 1 wherein the dirt collection area has at least one wall which is configured to convey particulate material to the air outlet other than due solely to the air flow through the dirt collection area.

5. The surface cleaning head of claim 1 wherein the dirt collection area has at least one wall that is configured to covey particulate material to the air outlet under at least one of the force of gravity and vibrations produced when the vacuum cleaner is in operation.

6. The surface cleaning head of claim 1 wherein the dirt collection area has a bottom wall that is sloped downwardly towards the air outlet of the dirt collection area.

7. The surface cleaning head of claim 1 wherein the dirt collection area has a bottom wall that is sloped inwardly and downwardly towards the air outlet of the dirt collection area.

8. The surface cleaning head of claim 1 wherein the dirt collection area has a bottom wall that is sloped inwardly towards the air outlet of the dirt collection area.

9. The surface cleaning head of claim 1 wherein the dirt collection area is configured to accelerate the airflow passing through the dirt collection area.

10. The surface cleaning head of claim 1 wherein the velocity of the air entering the air outlet in the downstream end of the dirt collection area is at least about 5 times greater than the velocity of air when it enters the dirty air inlet.

11. The surface cleaning head of claim 1 wherein the velocity of the air entering the air outlet in the downstream end of the dirt collection area is at least about 10 times greater than the velocity of air when it enters the dirty air inlet.

12. The surface cleaning head of claim 1 wherein the cross sectional area of the dirt collection area generally continuously decreases from the upstream end of the dirt collection area to the downstream end of the dirt collection area.

13. The surface cleaning head of claim 1 wherein the brushing member is a rotary brush.

14. The surface cleaning head of claim 1 wherein the downstream end has a smaller cross section than the upstream end.

15. A surface cleaning head for a vacuum cleaner comprising: a) a bottom wall having a dirty air inlet and a brushing member associated with the dirty air inlet; and, b) a dirt collection area having a bottom wall and positioned downstream from the dirty air inlet and configured to retain particulate material in the dirt collection area, the dirt collection area having an upstream end and a downstream end, the downstream end having an air outlet which extends upwardly from the bottom wall of the dirt collection area and is in air flow communication with a source of suction and at least one filtration member when the vacuum cleaner is in use.

16. The surface cleaning head of claim 15 wherein the surface cleaning head has a ramp the extends upwardly from a first end proximal the dirty air inlet a second end proximal the dirt collection area and the bottom wall of the dirt collection area is positioned below the second end of the ramp.

17. The surface cleaning head of claim 15 wherein the dirt collection area has at least one wall which is configured to convey particulate material to the air outlet other than due solely to the air flow through the dirt collection area.

18. The surface cleaning head of claim 15 wherein the dirt collection area has at least one wall that is configured to covey particulate material to the air outlet under at least one of the force of gravity and vibrations produced when the vacuum cleaner is in operation.

19. The surface cleaning head of claim 15 wherein the bottom wall of the dirt collection area is sloped downwardly towards the air outlet of the dirt collection area.

20. The surface cleaning head of claim 15 wherein the bottom wall of the dirt collection area is sloped inwardly and downwardly towards the air outlet of the dirt collection area.

21. The surface cleaning head of claim 15 wherein the bottom wall of the dirt collection area is sloped inwardly towards the air outlet of the dirt collection area.

22. The surface cleaning head of claim 15 wherein the dirt collection area is configured to accelerate the airflow passing through the dirt collection area.

23. The surface cleaning head of claim 15 wherein the velocity of the air entering the air outlet in the downstream end of the dirt collection area is at least about 5 times greater than the velocity of air when it enters the dirty air inlet.

24. The surface cleaning head of claim 15 wherein the velocity of the air entering the air outlet in the downstream end of the dirt collection area is at least about 10 times greater than the velocity of air when it enters the dirty air inlet.

25. The surface cleaning head of claim 15 wherein the cross sectional area of the dirt collection area generally continuously decreases from the upstream end of the dirt collection area to the downstream end of the dirt collection area.

26. The surface cleaning head of claim 15 wherein the brushing member is a rotary brush.

27. A method of cleaning a surface using a surface cleaning head having a dirty air inlet in fluid communication with a source of suction comprising: a) introducing a dirty air stream into the surface cleaning head through the dirty air inlet; b) passing the dirty air stream through a portion of the surface cleaning head which is configured to collect particulate matter which is introduced into the surface cleaning head through the dirty air inlet and which is not entrained in the dirty air stream as the particulate matter enters the dirty air inlet or which does not remain entrained in the dirty air stream; c) passing the dirty air stream through a portion of the surface cleaning head which is configured to increase the velocity of the dirty air stream; d) conveying the collected particulate matter to the position at which the velocity of the dirty air stream is increased; and, e) using the increased velocity of the dirt air stream to entrain at least some of the collected particulate matter.

28. The method as claimed in claim 27 further comprising the step of using mechanical action to draw particulate matter into the dirty air inlet.

29. The method as claimed in claim 27 further comprising the step of sweeping particulate matter into the dirty air inlet.

30. The method as claimed in claim 27 further comprising the step of using a rotating brush to at least assist in sweeping particulate matter into the dirty air inlet.