Cleaner head

Abstract

A cleaner head for a vacuum cleaning appliance includes a main body, a front agitator and a rear agitator, each agitator being rotatable relative to the main body, a mechanism for rotating the front agitator and the rear agitator, and a surface agitating edge located between the front agitator and the rear agitator.

Claims

1. A cleaner head for a vacuum cleaning appliance, comprising: a body; a brushbar arranged to rotate with respect to the body about a rotational axis, the brushbar having an outer surface, wherein a compliant material forms at least a portion of the outer surface; wherein an internal surface of the body has a curved portion that curves around at least a portion of the outer surface of the brushbar and forms a front edge of the cleaner head that extends in a longitudinal direction of the brushbar and is raised relative to a bottom of the body, so that when the bottom of the body is placed adjacent to a floor surface during use, a bottom of the front edge of the cleaner head is located higher than the rotational axis of the brushbar and is spaced further from the floor surface than the bottom of the body and defines an upper edge of an opening at the front of the cleaner head through which the brushbar is exposed, the brushbar is arranged such that the brushbar forms a seal between the curved portion of the internal surface of the body and the floor surface, the body comprises a suction chamber having a suction opening that is adjacent to the floor surface and through which a dirt-bearing air flow enters the cleaner head, and the suction chamber is located rearward of the brushbar so that the brushbar defines a front edge of the suction opening.

2. The cleaner head of claim 1, wherein the motor is located within the brushbar.

3. The cleaner head of claim 1, further comprising a drive mechanism comprising a motor and a transmission, wherein the transmission couples the motor to the brushbar.

4. The cleaner head of claim 3, wherein the transmission comprises a gear arrangement.

5. The cleaner head of claim 3, wherein the transmission comprises a driven member connected to the brushbar and a drive belt arranged to drive the driven member.

6. The cleaner head of claim 1, wherein the front edge of the cleaner is located forward of the rotational axis of the brushbar.

7. The cleaner head of claim 1, wherein the seal is formed between the front edge of the cleaner head and the floor surface.

8. The cleaner head of claim 1, wherein the curved portion extends around at least 20% of the circumference of the brushbar.

9. The cleaner head of claim 1, wherein the curved portion of the internal surface has a radius of curvature which is the same as the radius of the brushbar.

10. The cleaner head of claim 1, wherein the curved portion extends over the top of the brushbar.

11. The cleaner head of claim 1, wherein the compliant material forms at least 70%, preferably at least 85% and more preferably at least 95% of the outer surface.

12. The cleaner head of claim 1, wherein the compliant material comprises a flexible pile.

13. The cleaner head of claim 12, wherein the pile comprises filaments formed from one of metallic, carbon fibre, plastics, natural and composite material.

14. The cleaner head of claim 13, wherein the brushbar comprises a brushbar body, and the filaments are woven on to a flexible carrier member located about the brushbar body.

15. The cleaner head of claim 14, wherein the carrier member is adhered to the brushbar body.

16. A vacuum cleaner comprising the cleaner head of claim 1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) An embodiment of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

(2) FIG. 1 is a front perspective view, from above, of a cleaner head for a vacuum cleaning appliance;

(3) FIG. 2 is a front view of the cleaner head of FIG. 1;

(4) FIG. 3 is a bottom view of the cleaner head of FIG. 1;

(5) FIG. 4 is a left side view of the cleaner head of FIG. 1;

(6) FIG. 5 is a right side view of the cleaner head of FIG. 1, with part of the main body removed;

(7) FIG. 6 is a top view of the cleaner head of FIG. 1;

(8) FIG. 7 is a side sectional view taken along line A-A of FIG. 6, with the cleaner head located on a relatively hard floor surface; and

(9) FIG. 8 is the same view as FIG. 7, but with the cleaner head located on a carpeted floor surface.

DETAILED DESCRIPTION OF THE INVENTION

(10) FIGS. 1 to 4 and FIG. 6 illustrate an embodiment of a cleaner head 10 for a vacuum cleaning appliance. In this embodiment, the cleaner head 10 is arranged to be connectable to a wand or hose of a cylinder vacuum cleaning appliance. The cleaner head 10 comprises a main body 12 and a conduit 14 connected to the main body 12. The main body 12 comprises an upper section 16, side plates 18, 20 and a lower section 22. The upper section 16 may be integral with the lower section 22, with the side plates 18, 20 being connected to the upper section 16 and the lower section 22 of the main body 12. The upper section 16 of the main body 12 has a raised front edge 24. A rear portion 26 of the lower section 22 of the main body 12 protrudes rearwardly beyond the upper section 16 of the main body 12.

(11) The lower section 22 of the main body 12 comprises a bottom surface 28 which, in use, faces a floor surface to be cleaned and, as described in more detail below, engages the surface of a carpeted floor surface. The bottom surface 28 is generally planar, and comprises a trailing section 30 and a side section 32. A rear surface 33 of the lower section 22 curves upwardly and rearwardly from the rear of the trailing section 30.

(12) The main body 12 comprises a downwardly-facing suction opening 34 through which a dirt-bearing air flow enters the cleaner head 10. The suction opening 34 is generally rectangular in shape, and is delimited in part by relatively short side walls 36, 38 and a relatively long rear wall 40. The side section 32 of the bottom surface 28 comprises the side wall 36, the side plate 18 of the main body comprises the side wall 38, and the trailing section 30 of the bottom surface 28 comprises the rear wall 40. As shown in FIG. 7, the rear wall 40 of the suction opening 34 is curved or inclined forwardly relative to the bottom surface 28 to sweep the fibres of a rug or deeply piled carpeted floor surface beneath the trailing section 30 of the bottom surface 28 as the cleaner head 10 is manoeuvred over the floor surface. The angle of inclination of the rear wall 40 relative to the bottom surface 28 is preferably in the range from 40 to 50. A rear edge 42 of the suction opening 34 is located at the intersection between the rear wall 40 and the trailing section 30 of the bottom surface 28, and extends substantially uninterruptedly between the side walls 36, 38. The side walls 36, 38 are generally orthogonal to the bottom surface 28.

(13) With particular reference to FIG. 3 and FIG. 7, a surface agitating member 44 extends across the suction opening 34, generally parallel to the rear edge 42 of the suction opening 34. The surface agitating member 44 is connected to the side walls 36, 38 of the suction opening 34. The surface agitating member 44 comprises a front surface 46 and a rear surface 48 which each extend substantially the entire length of the surface agitating member 44, and which intersect to define a surface agitating edge 50. To reduce the resistance to the manoeuvring of the cleaner head 10 over a carpeted surface, the lower part of the front surface 46 of the surface agitating member 44 is also inclined forwardly relative to the bottom surface 28 to sweep the fibres of a rug or deeply piled carpeted floor surface beneath the surface agitating edge 50 as the cleaner head 10 is manoeuvred over the floor surface. The angle of inclination of the front surface 46 of the surface agitating member 44 relative to the bottom surface 28 at the intersection between the front surface 46 and the rear surface 48 is preferably in the range from 10 to 30. The angle subtended between the front surface 46 and the rear surface 48 at the surface agitating edge 50 is preferably in the range from 50 to 80. The surface agitating edge 50 is preferably relative sharp, preferably having a radius of curvature less than 0.5 mm.

(14) To prevent the surface agitating edge 50 from scratching or otherwise marking a hard floor surface as the cleaner head 10 is manoeuvred over such a surface, the main body 12 comprises at least one surface engaging support member which serves to space the surface agitating edge 50 from such a surface. In this embodiment, the cleaner head 10 comprises a plurality of surface engaging support members which are each in the form of a rolling element. Two relatively wide rolling elements 52 are each rotatably mounted within a respective aperture 54 formed in the rear portion 26 of the lower section 22 of the main body 12, whereas two relatively narrow rolling elements 56 are each rotatably connected to the surface agitating member 44 and located towards a respective end of the surface agitating member 44 so that the surface agitating edge 50 is located therebetween. As illustrated in FIG. 7, the rolling elements 52, 56 protrude downwardly beyond both the bottom surface 28 of the lower section 22 of the main body 12 and the surface agitating edge 50 so that when the cleaner head 10 is located on a hard floor surface H with the rolling elements 52, 56 engaging that surface, the bottom surface 28 of the main body 12 and the surface agitating edge 50 are spaced from that surface.

(15) Returning to FIG. 3, a plurality of rug strips 58 for guiding the movement of the cleaner head 10 over a rug or deeply piled carpeted floor surface extend across part of the suction opening 38. The rug strips 58 are connected to, and preferably integral with, the surface agitating member 44, and extend from the surface agitating member 44 to the rear wall 40 of the suction opening 38, to which the rug strips 58 are connected. The rug strips 58 are substantially parallel to the side walls 36, 38 of the suction opening 34.

(16) The cleaner head 10 comprises a front agitator 60 and a rear agitator 62 located behind the front agitator 60 for agitating dirt and dust located on a floor surface. In this embodiment, each of the agitators 60, 62 comprises a brush bar which is rotatable relative to the main body 12 about a rotational axis. The rotational axes A, B of the agitators 60, 62 are substantially parallel, and are also substantially parallel to the front edge 24 of the main body 12, the rear edge 42 of the suction opening 34 and the surface agitating edge 50.

(17) The front agitator 60 and the rear agitator 62 are dissimilar. With reference again to FIGS. 3 and 7, the front agitator 60 comprises a generally cylindrical body 64 which rotates about the longitudinal axis thereof. The body 64 has an outer surface comprising a pile 66 formed from relatively flexible filaments. In this example, the pile 66 is similar to the raised or fluffy surface of a carpet, rug or cloth, and comprises filaments woven on to a fabric carrier member (not shown) attached to the body 64, for example using an adhesive. The length of the filaments of the pile 66 is preferably in the range from 5 to 15 mm. The fabric carrier member may be in the form of a strip wound on to the body 64 so that the pile 66 is substantially continuous, substantially covering the outer surface of the body 64. Alternatively, the carrier member may be in the form of a cylindrical sleeve into which the body 64 is inserted.

(18) The length of the filaments of the front agitator 60 is selected so that the pile 66 protrudes downwardly beyond the bottom surface 28 of the main body 12 and the surface agitating edge 50, and at least as far as the rolling elements 52, 56. Consequently, when the cleaner head 10 is located on a hard floor surface H, as illustrated in FIG. 7, the pile 66 engages the hard floor surface H to enable dirt and debris to be swept from the hard floor surface H with rotation of the front agitator 60 relative to the main body 12. With the pile 66 substantially covering the body 64 of the front agitator 60, the pile 66 can engage and form a seal with the hard floor surface H during rotation of the front agitator 60. The pile 66 therefore defines the front edge 68 of the suction opening 34 of the cleaner head 10. The front edge 68 can remain in contact with a floor surface as the cleaner head 10 is manoeuvred over the floor surface so that, in use, a pressure difference established between the air passing through the cleaner head 10 and the external environment is greater than that established in a cleaner head 10 in which the entire periphery of the suction opening is spaced from the floor surface, thereby improving the entrainment within an airflow entering the cleaner head 10 of debris of dirt and dust located in crevices in the hard floor surface H.

(19) As mentioned earlier, the upper section 16 of the main body 12 has a raised front edge 24. The front agitator 60 is arranged so that the rotational axis A of the front agitator 60 is located both behind and beneath the front edge 24. The length of the filaments of the pile 66 of the front agitator 60 is selected so that the pile 66 extends forwardly beyond the front edge 24 of the main body 12. This can be seen most clearly in FIGS. 4 and 5. As a result, the pile 66 of the front agitator 60 provides the forward extremity of the cleaner head 10. The pile 66 can therefore act as a relatively soft and flexible front bumper for the cleaner head 10, meaning that the front of the cleaner head 10 can engage walls, furniture or other such objects upstanding from a floor surface without marking these objects. Furthermore, depending on the distance by which the pile 66 protrudes forwardly from the front edge 24 of the main body 12 the cleaner head 10 can be pushed forward against an upstanding object so that the pile 66 can sweep dirt and debris from the portion of the floor surface adjoining the upstanding object before the front edge 24 comes into contact with the up standing object.

(20) The filaments of the front agitator 60 may be formed from one of a plastics material or a natural material. Alternatively, at least some of the filaments of the front agitator 60 may be formed from carbon fibre material, metallic material, or other composite material. Consequently, in this latter case the surface resistivity of the filaments of the pile 66 may be in the range from 1105 to 11012 /sq. Providing the front agitator 60 with a flexible, electrically conductive outer surface can enable static electricity residing on a floor surface to be cleaned to be discharged upon contact between the front agitator 60 and the floor surface. In turn, this can enable fine dust and powder which would otherwise be attracted to the floor surface to be dislodged from the floor surface by the front agitator 60.

(21) The rear agitator 62 also comprises a generally cylindrical body 70 which rotates about the longitudinal axis thereof. Instead of a relatively flexible pile formed from filaments being located about the body 70, the rear agitator 62 comprises relatively stiff surface engaging elements which in this embodiment are in the form of relatively stiff bristles 72 protruding radially outwardly from the body 70. As shown in FIG. 3, the bristles 72 are arranged in a plurality of clusters arranged in a helical formation at regular intervals along the body 70.

(22) The rear agitator 62 is arranged so that, during rotation of the rear agitator 62 about its rotational axis B, the bristles 72 protrude downwardly through the suction opening 34 of the main body 12, between the rug strips 58 and beyond the surface agitating edge 50. However, as illustrated in FIG. 7 the rear agitator 62 is also arranged so that the bristles 72 do not protrude downwardly beyond the rolling elements 52, 56 or the pile 66 of the front agitator 60. Consequently, when the cleaner head is located on a relatively hard floor surface H, the bristles 72 of the rear agitator are spaced from the floor surface H. This means that the rear agitator 62 can be rotated simultaneously with the front agitator 60 irrespective of the nature of the floor surface on which the cleaner head 10 is located without the floor surface being scratched or otherwise marked by the bristles 72 of the rear agitator 62. This can enable a relatively simple drive mechanism to be used to rotate both the front agitator 60 and the rear agitator 62, as described in more detail below.

(23) As also shown in FIG. 7, the rear agitator 62 is arranged so that the bristles 72 engage and move through the pile 66 of the front agitator 60 during use of the cleaner head 10. This can enable the bristles 72 of the rear agitator 62 to dislodge matter which may become caught or entangled between or about the filaments of the pile 66 of the front agitator 60. In addition to enabling the exposed front portion of the front agitator 60 to maintain a relatively clean appearance, the removal of dirt or debris from the pile 66 of the front agitator 60 can enable the cleaner head 10 to maintain a relatively uniform cleaning performance, for example through preserving the seal formed between the front edge 68 of the suction opening 34 and the floor surface.

(24) The bristles 72 of the rear agitator 62 are preferably formed from an electrically insulating, plastics material, such as nylon, and so may have a surface resistivity in the range from 11012 to 11016 /sq. Alternatively, at least some of the bristles 72 may be formed from a metallic or composite material and so may have a surface resistivity within the aforementioned range for the pile 66 of the front agitator 60 in order to discharge any static electricity residing on a carpeted floor surface and/or, if the pile 66 is formed from a natural or electrically insulating material, on the pile 66 of the front agitator 60.

(25) Optionally, a window 74 is located in the upper section 16 of the main body 12 to allow a user to view the rear agitator 62 during use of the cleaner head 10 to check that the rear agitator 62 has not become so entangled with hair or other fibres as to impair the rotation thereof relative to the main body 12. As illustrated in FIG. 6, the window 74 may be a relatively small window located centrally on the upper surface 16 of the main body 12. Alternatively, the size of the window 74 may be increased to enable a user to view a greater proportion of the rear agitator 62 during use of the cleaner head 10.

(26) FIG. 5 illustrates a drive mechanism 80 for rotating the front agitator 60 and the rear agitator 62 relative to the main body 12. The drive mechanism 80 comprises a motor 82 located within a motor housing 84 formed in the upper section 16 of the main body 12, and which is located behind the rear agitator 62. The motor 82 is supplied with electrical power by leads (not shown) which pass through the conduit 14 and terminate with terminals located adjacent the air outlet of the conduit 14. These terminals are connectable to a power leads located, in the case of an upright vacuum cleaning appliance, in the main body of the vacuum cleaning appliance or, in the case of a cylinder vacuum cleaning appliance, at the end of a wand connected by a hose to the main body of the appliance.

(27) The drive mechanism 80 further comprises a first drive member 86, preferably in the form of a pulley, mounted on a first drive shaft 88. The first drive shaft 88 is connected to the motor 80. The first drive member 86 is connected by a first drive belt 90 to a first driven member 92, also preferably in the form of a pulley. The first driven member 92 is mounted on a second drive shaft 94 for rotation about an axis which is substantially parallel to the rotational axis of the first drive shaft 88. One of the first driven member 92 and the second drive shaft 94 is connected to one end of the body 70 of the rear agitator 62 so as to rotate the rear agitator 62 about its rotational axis B. The other end of the body 70 of the rear agitator 62 is rotatably supported by formations disposed on the side plate 18 of the main body 12.

(28) The drive mechanism 80 also comprises a second drive member 96, preferably in the form of a pulley, mounted on the second drive shaft 94 for rotation with the first driven member 92. The second drive member 96 has a smaller radius than the first driven member 92. The second drive member 96 is connected by a second drive belt 98 to a second driven member 100, also preferably in the form of a pulley. The second driven member 100 has a larger radius than the second drive member 96. The second driven member 100 is mounted on a third drive shaft 102 for rotation about an axis which is substantially parallel to the rotational axis of the first drive shaft 88. One of the second driven member 100 and the third drive shaft 102 is connected to one end of the body 64 of the front agitator 60 so as to rotate the front agitator 60 about its rotational axis A. Similar to the rear agitator 62, the other end of the body 64 of the front agitator 60 is rotatably supported by formations disposed on the side plate 18 of the main body 12.

(29) The arrangement of the drive mechanism 80 is such that, upon activation of the motor 80, the front agitator 60 and the rear agitator 62 rotate in the same direction so as to sweep dirt and debris on a floor surface rearwardly towards the conduit 14. The arrangement of the drive mechanism 80 is also such that the front agitator 60 and the rear agitator 62 are rotated at different speeds. The front agitator 60 is rotated at a first speed, and the rear agitator 62 at a second speed which is greater than the first speed. In this embodiment the front agitator 60 is rotated at a speed of around 1,500 rpm, and the rear agitator 62 is rotated at a speed of around 3,700 rpm. However, the speeds of rotation of the front agitator 60 and the rear agitator 62 are not restricted to these values; the speed of rotation of the rear agitator 62 is preferably at least twice the speed of rotation of the front agitator 60, and may be as much as three times or four times the speed of rotation of the front agitator 60.

(30) Returning to FIG. 7, the main body 12 comprises an air outlet 108 located towards the rear of the main body 12 for conveying a dirt-bearing air flow to the conduit 14. To minimise the height of the cleaner head 10, the air outlet 108 is preferably located behind the rear agitator 62. The main body 12 also comprises a suction channel which extends from the suction opening 34 to the air outlet 108. The suction channel can be considered as being divided into a front section 110 and a rear section 112, with the surface agitating edge 50 being located between the front section 110 and the rear section 112 of the suction channel. In use, a dirt-bearing air flow passes from the front section 110 to the rear section 112 of the suction channel over the surface agitating edge 50.

(31) With the front edge 24 of the main body 12 being raised above the rotational axis A of the front agitator 60, there is a risk that dirt and debris which has been swept from the floor surface by the front agitator 60 may be subsequently thrown forward from the front of the cleaner head 10 if it is not dislodged by the bristles 72 of the rear agitator 62 and drawn into the airflow passing through the cleaner head 10. In view of this, the upper section 16 of the main body 12 comprises a barrier member 116 which protrudes downwardly from the upper section 16 towards the suction opening 34. The barrier member 116 is shown in FIGS. 7 and 8. The barrier member 116 is located between the front agitator 60 and the rear agitator 62, and preferably extends substantially the entire length of the front agitator 60. As illustrated, the barrier member 116 extends into the pile 66 of the front agitator 60 to dislodge debris and dirt from between the filaments of the pile 66 for entrainment within the air flow.

(32) Returning to FIGS. 1 and 6, the conduit 14 comprises a front section 120 and a rear section 122. To facilitate the manoeuvring of the cleaner head 10 over a floor surface, the front section 120 is pivotably connected to the main body 12 of cleaner head for movement relative thereto about a first pivot axis which is substantially parallel to the rotational axes A, B of the front agitator 60 and the rear agitator 62. The rear section 122 of the conduit 14 is connected to the neck 126 of the front section 50 of the conduit 14 for pivotal movement relative thereto about a second pivot axis angled to the first pivot axis.

(33) The front section 120 comprises a head 124 pivotably connected to the main body 12, and a neck 126 extending from the head 124 to the rear section 122 of the conduit 14. The head 124 is positioned within a recess located centrally in the upper section 16 of the main body 12. The head 124 has a substantially cylindrical outer surface which is open at each end thereof to receive an air flow from the rear section 112 of the suction channel, and is connected to the upper section 16 so that the head 124 is free to rotate about its longitudinal axis. The bottom of the recess within the upper section 16 of the main body 12 is delimited by a curved support surface 128 for supporting the head 124. The support surface 128 preferably has a radius of curvature which is substantially the same as that of the outer surface of the head 124. In addition to supporting the head 124, the support surface 128 also serves to guide fluid into the head 124 from the rear section 112 of the suction channel.

(34) The neck 126 is connected to the head 124 substantially midway between the open ends of the head 124, and in this embodiment is integral with the head 124. The neck 126 extends away from the head 124 in a direction which is substantially orthogonal to the longitudinal axis of the head 124. Consequently, as air passes through the head 124 and into the neck 126, the air changes direction by around 90. To reduce turbulence within the head 124, the head 124 comprises two guide surfaces (not shown) each for guiding fluid entering the head 124 through a respective one of the open ends towards the neck 126. The guide surfaces are preferably integral with the inner surface of the head 124, and arranged so that each guide surface curves away from the inner surface of the head 124 towards the neck 126 to meet the other guide surface at an apex 130 extending across the bore of the head 124.

(35) The connection between the front section 120 and the rear section 122 of the conduit 14 is effected by the connection of the air outlet 132 of the neck 126 of the front section 120 to the air inlet 134 of the rear section 122. The air outlet 132 of the neck 126 is substantially cylindrical, and is angled downwardly (as illustrated in FIG. 7) towards a floor surface to be cleaned. The air inlet 134 of the rear section 122 is also substantially cylindrical and is angled upwardly (as also illustrated in FIG. 7) away from the floor surface.

(36) The rear section 122 of the conduit 14 comprises an air outlet 136 which is connectable to a wand, hose or other such duct of a cylinder vacuum cleaning appliance which comprises dirt and dust separating apparatus and a motor-driven fan unit for drawing dirt-bearing air into the main body 12 of the cleaner head 10. During use of the vacuum cleaning appliance, an air flow is drawn into the cleaner head 10 through the suction opening 34. The air flow passes through the suction channel to the air outlet 108 of the main body 12. The air flow then passes through the conduit 14 and enters, for example, the wand of the cleaning appliance. The motor 82 of the drive mechanism 80 is activated to rotate simultaneously the front agitator 60 and the rear agitator 62.

(37) When the cleaner head 10 is located on a relatively hard floor surface H, as illustrated in FIG. 7, a pressure difference is generated between the air passing through the cleaner head 10 and the external environment. This pressure difference generates a force which acts downwardly on the main body 12 of the cleaner head 10 towards the floor surface. As the rolling elements 52, 56 and the pile 66 of the front agitator 60 protrude downwardly beyond the surface agitating edge 50 and the bristles 72 of the rear agitator, only the rolling elements 52, 56 and the pile 66 of the front agitator 60 engage the hard floor surface H. The bottom surface 28 of the main body 12 is spaced from the hard floor surface H, and so debris located on the hard floor surface H can become entrained within the air flow generated by the cleaning appliance, with the result that a dirt-bearing air flow can flow unrestrictedly beneath the bottom surface 28 of the main body 12 and into the suction channel through the suction opening 34. With the rotation of the front agitator 60 relative to the main body 12, the pile 66 of the front agitator 60 is able to sweep dirt and debris from the hard floor surface H into the front section 110 of the suction channel. This debris can be thrown rearwardly by the pile 66 of the front agitator 60 and become entrained within the air flow passing through the suction channel to the air outlet 108. In the event that any debris has become caught or otherwise trapped between the filaments of the pile 66, this debris can be dislodged from the filaments by the rotating bristles 72 of the rear agitator 62 or the barrier member 116.

(38) When the cleaner head 10 is located on a carpeted floor surface C, as illustrated in FIG. 8, the rolling elements 52, 56 and the pile 66 of the front agitator 60 are pushed into the fibres of the carpeted floor surface C under the weight of the cleaner head 10 and the force acting downwardly on the main body 12. As the support members 52, 56 sink into the carpet, the bottom surface 28 of the main body 12 comes into contact with the carpeted floor surface C. As the surface agitating edge 50 and the bristles 72 of the rear agitator 62 protrude downwardly beyond the bottom surface 28 of the main body 12, dirt and dust within the fibres of the carpeted floor surface C can be agitated by the surface agitating edge 50 and the rear agitator 62, and become entrained within the air flow drawn into the suction channel.