GB2415890A

GB2415890A - Vacuum cleaner nozzle with pivotal base plate

Info

Publication number: GB2415890A
Application number: GB0427017A
Authority: GB
Inventors: Kyoung-Woung Kim
Original assignee: Samsung Gwangju Electronics Co Ltd
Current assignee: Samsung Electronics Co Ltd
Priority date: 2004-07-09
Filing date: 2004-12-09
Publication date: 2006-01-11
Anticipated expiration: 2024-12-09
Also published as: KR100582519B1; CN1718150A; US20060005350A1; RU2283612C1; FR2872693A1; AU2004237799B2; RU2004137458A; KR20060004262A; GB2415890B; JP2006021019A; AU2004237799A1; GB0427017D0; DE102004061855A1

Abstract

A nozzle unit for a vacuum cleaner has a base plate (150), with a suction port through which dust is drawn, rotatably disposed under a cover (100) to contact with a surface to be cleaned. Even when the rear end of the nozzle unit is lifted away from that surface during a cleaning operation, the base plate (150) maintains close contact with that surface by pivotally rotating downwards, thus enhancing the cleaning efficiency. The cover (100) may further comprise a foot switch (314) rotatably disposed in the cover. The foot switch (314) governs the extension of a brush plate (350) situated between the cover (100) and the base plate (150).

Description

P515943CR 1 2415890 Nozzle Unit for a Vacuum Cleaner Ales application is

related to copending U.S. applications entitled "Suction Brush Assembly Having Rotation Roller for Sweeping Dust," Serial No. 10/195,595, filed July 16, 2002, uld "Bendable Suction Brush for Vacuum Cleaner," Senal No. 10/851,080, filed May 24, 2()()4.

This invention relates to a vacuum cleaner, and in partculau- to a vacuum cleaner nozzle unit that adapts to different characteristics of a surface to be cle used, so as to enhance cleauling elTiciency and accuracy.

A vacuum cleaner generally draws In dust and contamu1 lets (hereinafter reterrcd to as 'dust") from a surface to be cleaned using a suction force generated by driving a motor disposal U1 the body of the vacuous cleaner. Figure I shows a conventional vacuum cleaner having a cleaner body 10, a nozzle unit 30, rued au1 extension tube 20. The cleaner body I O accommodates a motor (not shown) Ior generating the suction force, and the nozzle cubit 3() is provided with,U1 inlet 39 which faces the surface to be cleaned, and through wretch dust is drawn in. The dust bra In through the nozzle cubit 30 flows through the extension tube 20 whicl1 leads to the cle.uler body 10.

The nozzle Unit 30 includes au1 upper housing 34 and a lower housing 38 coupled by a plurality of bolts 40, the inlet 39 being fonncd in the lower housing. The extension tube 2() Includes a connector 26 rotatably mounted on the nozzle cult 30, .U1 extension tube 24 that mates with the connector, sued a hose 22 that mates with the extension tube at one end and con lCCtS WItl1 the cleaner body 10 at the other end.

P5 1 5941GB 2 The vacuum cleaner draws in dust from the surface, such as a carpet or floor, to be cleaned, while a user of the vacuum cleaner moves the nozzle unit 30 back and forth. However, when the nozzle lust 30 is moved backwards, its rear end is often lifted away from the surface to be cleaned. With the rear end of the nozzle unit 30 spaced from the surface to be cleaned, the base of the lower housing 38 cannot closely contact that surface, thus leading to a loss of the suction force, and a deterioration of the cleaning efficiency. Also, when using the vacuum cleaner, the base of the lower housing 38 can directly contact the surface, such as a floor, to be cleaned and thus scratch the floor.

In addition, since a plurality of bolts 40 are required to couple the upper housing 34 and the lower hocusing 38, the manufacturing costs are increased, and productivity is decreased due to the increased number of parts and required assembly time.

An aim of the invention is to overcome the above disadvantages and problems of the conventional arrangement, Could to provide an improved nozzle unit for a vacuum cleaner with enhanced cleaning accuracy and cleaning efficiency.

Another aim of the invention is to provide an improved nozzle unit for a vacuum cleaner, which is capable of preventing its base from scratching the floor during a cleaning operation.

Yet another aim of the invention is to provide a nozzle unit for a vacuum cleaner that can be assembled without employing fastening members such as bolts.

The present invention provides a nozzle unit for a vacuum cleaner, the nozzle unit comprising: a cover; and P5 1 5943GB 3 a base plate rotatably connected to the cover, the base plate having a suction port through which dust is drawn in from a surface to be cleaned, the dust being drawn in by a suction force generated by a vacuum generator disposed in the body ofthe vacuum cleaner.

The nozzle Licit may further comprise a resilient member disposed between the base plate and the cover for biasing an end ofthe base plate in a predetermined direction.

The nozzle unit may further comprise a base plate stopper disposed on at least one of the base plate and the cover to limit rotation of the base plate. Accordingly, the base plate cau1 rotate over a predetermined angular range.

The nozzle unit may further comprise a base plate fixings unit disposed between the cover and the base plate for selectively fixing the base plate to the cover. The base plate fixing unit may have a foot switch rotatably disposed in the cover, and an operation lolob exposed to the outside and extending through an opening in the cover, a first locking part, a brush plate rotatably disposed in the cover for rotation in association with the foot switch, and a second locking part complementary with the first locking part for locking and unlocking the brush plate.

The nozzle unit may further comprise a brush disposed on the brush plate, the brush protruding between the cover auld the base plate according to the rotational position of the brusl1 plate.

Advantageously, the nozzle further comprises foot SWItC}1 support fibs formed on the cover at a predetermined spacing, each of said ribs having an axis hole connectable with a respective toot switch stub shaft of the foot switch, P5 1 594lGB wherein at least one of each foot switch stub shaft and the associated brush plate support rib is provided with a slope to facilitate that foot switch stub shaft being inserted into the axis hole of the associated support rib.

Preferably, the nozzle unit further comprises brush plate support ribs formed on the cover at a prcdetennned spacing, each of said ribs having an axis hole connectable with a respective brush plate stub shaft of the brush plate, wherein at least one of each brush plate stub shaft and the associated brush plate support rib is provided with a slope to facilitate that brush plate stub shaft being inserted into the axis hole ofthe associated support rib.

Conveniently, the nozzle unit further comprises: base plate stub shafts formed on at least one ofthe base plate and the cover; and base plate support ribs, each having an axis hole connectable with a respective base plate stub shaft, and base plate support ribs formed on at least one of the cover and the base plate to complement the base plate stub shafts, wherein at least one of each base plate stub shaft and the associated base plate support rib is provided with a slope to facilitate that base plate stub shaft being inserted into the axis hole of the associated support rib.

The nozzle unit may further comprise: a wheel arid a wheel shaft; a wheelreceiving part formed at a rear of the cover for receiving the wheel, and having a shaft hole through which the wheel shaft is inserted; a locking projection formed on the wheel shaft; and PS 1 5943GR 5 a locking recess donned adjacent to the shaft hole to complement the locking projection so that the wheel shaft can be inserted into, and locked with, the shad hole.

The invention also provides a nozzle unit for a vacuum cleaner, the nozzle unit comprising: S a cover; a base plate rotatably connected to the cover, the base plate having a suction port through which dust is drawn in from a surface to be cleaned, the dust being drawn in by a suction force generated by a vacuum generator disposed in the body of the vaeurun cleaner, a foot switch rotatably disposed in the cover, and having an operation knob extending through an opening In the cover and a first locking part; a brush plate rotatably disposed in the cover to rotate in association with the foot switch, and having a second locking part complementary with the first locking part, for locking and unlocking the brush plate; and a brush associated with the brush plate, and protndulg between the cover and the base 1 S plate according to the rotational position of the brush plate.

As mentioned above, the nozzle unit has a cover, a base plate rotatably disposed in the cover, and a base plate fixing unit disposed between the cover and the base plate. The base plate fixing Unit has a foot switch rotatably disposed in the cover and a brush plate rotatably disposed in the cover to rotate in association with the foot switch. The foot switch has But operation knob exposed to the outside so that the user can rotate the foot switch. A respective first locking part is fomled at both ends of the foot switch. A complementary second locking part is lomned on the brush plate.

When the second locking parts rotate in association with the rotation of the first locking parts, a baush disposed at the front of the baush plate protrudes with respect to the cover. A resilient

J

P5 1 5943GB member is interposed between the front part of the brush plate and the base plate so as to press together the front part ofthe brush plate and the base plate.

The user can select a rotation mode and a stationary mode of the base plate by actuation of the operation knob. If the user selects the rotation mode, the front end of the base plate is biased downwardly by the resilient member and the rear end is supported by a base plate stopper. When the rear side of the nozzle unit is lifted away from the surface to be cleaned, the base plate rotates and closely contacts that surface due to the suction force between that and the base plate, and the force applied on the nozzle unit by the user.

When the user selects the stationary mode and rotates the foot switch by using the operation knob, the first locking parts press downwards onto the second locking parts so as to rotate the brush plate downwardly. The brush at the front end of the brush plate protrudes downwardly from th base plate. Since the nozzle unit is supported by a wheel at the rear end and by the brush, cleaning Is performed with a predetermined gap from the surface to be cleaned. Accordingly, a surface such as a floor is not scratched. In addition, as the brush plate rotates downwards, the resilient member presses the front end ofthe base plate downwardly. Thus, the front end ofthe base plate is supported by the resilient member, and the base plate stopper at the rear end ofthe base plate is supported by the end of brush plate support ribs formed on the cover, so that the base plate is fixed with respect to the cover.

The foot switch, the brush plate, and the base plate, each have stub shafts. The cover is provided with support ribs, each having an axis hole corresponding to a respective stab shaft. The stub shaft and the support ribs are sloped so that the stub shaft can be smoothly inserted into the axis P5 1 5943G8 7 holes. As constructed above, the assembly of the nozzle unit is improved, and the number of parts is reduced without having to use additional fastening means, such as bolts.

The invention will now be described in greater detail, by way of example, with reference to the drawings, in which: Figure I is a perspective view of a conventional vacuum clcancr; Figure 2 is a perspective view of a vacuum cleaner nozzle relit constructed according to the invention, showing the nozzle unit assembled; Figure 3 is an exploded view ofthe nozzle unit of Figue ?; Figures 4A and 4B arc partial cross-sectional views on the lines 4A-4A and 4B-4B respected of Figure 3; Figure 5 is a perspective view ofthe base plate ofthe nozlc unit of 1-igue 3; Figure 6 is a cross-section taken on the line VI-VI of Figure 3; Figure 7 IS a cross-section taken on the line VII-VII of Find e 3, Figures 8A and 8B are side elevational views of the nozzle Flit of E7igrure 3, showing a portion of the nozzle unit removed and with the nozzle unit in a fH-st operational mode; and Figures 9A and 9B arc side clevational views of the nozzle unit of Figure 3 with a portion of the nozzle unit removed and with the nozz..le cubit in a second operational mode.

Referring to the drawings, Figures 2 and 3 show a vacuous cleauler nozzle unit having a cover 10() forming an upper casing, a base plate 150 rotatably fiend under the cover 100, a base plate fixing unit 30O, a pair of wheels 418, and a wheel support shall 42(). The base plate fixing, Cubit 300 Is rotatably disposed between the cover 100 and the base plate I SO. The unit 300 allows the base plate 150 to be rotated to diffeecnt operating positions depending on the type of su-lace, sucl1 as a P5 1 5941( ,8 8 carpet or a floor, to be cleaned. The wheel shaft 420 is rotatably mounted to the rear end 102 of the cover 100, so that the wheels 418 can rotate.

The cover 100 is provided with stub shafts 152 defining a first rotary axis for the base plate 150, the shub shafts extending inwardly from the inner sidewalls of the cover. The cover 100 is provided with two base plate support ribs 157, each of which is provided with an axis hole 158, which holes align with second stub shafts 156 (see Figure 5) which are coaxial with respect to the first rotary axis. A suction duct 108 is formed between the support ribs 157, the suction duct being in fluid communication with an extension tube connector 500. An operang 104 is formed at the upper side of the cover 100 for receiving an operation knob 314. Four brush plate support ribs 384 are formed in the cover 100 for rotatably fixing a brush plate 350. Each brush plate support rib 384 is provided with a brush plate axis hole 380 (see Figure 4B). Two foot switch support ribs 336 are provided in the cover 100 for rotatably fixing a foot switch 310 to the cover. Each foot switch support rib 336 is provided with a foot switch axis hole 334 into which a respective foot switch rotary shub shaft 330 is inserted. The foot switch rotary shub shafts 330 are formed at the opposite ends ofthe foot switch 310. A wheel-receiving part 400 is formed at the rear end ofthe cover 100, that part receiving the extension tube connector 500 and the wheels 418. The wheel receiving part 400 is provided with wheel shaft holes 410 for lateral insertion of the wheel shaft 420. An axis hole (not shown) is formed at the front end of the extension tube connector 500 corresponding to the wheel shaft holes 410. The wheel shaft 420 penetrates through the axis hole and the wheel shaft holes 410 so that the extension tube connector 500 and the wheels 418 are rotatably fixed to the cover 100.

Both sidewalls of the base plate 150 are provided with a first axis hole 154 corresponding to the first rotary axis defiecd by the snub shafts 152. Each first axis hole 154 is aligned with a respective P5 1 5943GB 9 first stub shaft 152 so as to enable the base plate 150 to rotate with respect to the cover.

Accordingly, even when the rear side of the nozzle unit lifts away from the surface to be cleaned, the base plate 150 rotates with respect to the cover 100 to remain in close contact with that surface. A dust transfer channel 172 is formed at the bottom of the base plate 150, the dust transfer channel leading to a suction port 176. Respective spacers 174 are disposed in front, and to the rear, of the suction port 176 for maintaining a space between the base plate 150 and the surface to be cleaned. A mount 160 (see Figure 5) is fommed at the rear end under the base plate 150, a rubber lip 168 being mounted on the mount for swecpng dust positioned behind the suction port 176.

The base plate fixing unit 300 includes the foot switch 310 which is rotatably fixed to the cover 100, and the brush plate 350 is mounted in the cover and wdcr the hoot switch for rotation in association with the foot switch.

The operation knob 314 is exposed through an opening 104 formed on the cover 100 so that the user of the vacuum cleaner can control the foot switch 310 from the outside. A first stopper 324 is formed at a rear end of the operation knob 314 for limiting excessive rotation of the foot switch 310. A first locking part (rib) 318 is fomled at that end of the Coot switch 310 and extends downwardly from the operation knob 314. A similar first locking part 318 is t'ormed at the other end of the foot switch 310. The foot switch rotary stub shafts 330 are inserted into the foot Switch axis holes 334 of the cover 100, so that the foot switch 310 is rotatably fixed to the cover 100.

Each foot switch rotary stub shaft 330 has a slope S facilitating smooth insertion into the respective foot switch axis hole 334. A second stopper 328 is formed at the centre of the foot switch 310 to link both ends of the foot switch, and to rcstran the foot switch from rotating in the P5 1 5943GB 10 other direction. The second stopper 328 restrains the foot switch 310 from rotating in the other direction over a predetermined angle by contacting the suction duct 108.

Two baush plate stub shafts 376 are formed at the rear end ofthe brush plate 350. The stub shafts 376 arc inserted into the brush plate axis holes 380 (see Figure 4B), so that the brush plate 350 is rotatably fixed at the cover 100. A pair of second locking parts 358 are formed at the front of the stub shafts 376 and contact the first locking parts 318. A receptor 210 is formed at the centre of the front of the brush plate 350 for receiving a coil spring 200. The coil spring 200 could be replaced by any suitable resilient member. The coil spring 200 is securely inserted into the receptor 210 at one end, and is fixed to the front end ofthe base plate 150 at the other end, so as to bias the base plate 150 in the direction of the arrow A (see Figure 3). The front end of the brush plate 350 is provided with a mount 368 for mounting a brush 372. The brush 372 is mounted at the front end of the brush plate 350, and is vertically movable with respect to the cover 100 depending on the rotation of the brush plate. The brush plate 350 rotates when the first locking parts 318 press and rotate the second locking parts 358.

Referring to Figure 3, the nozzle unit is assembled by fixing the foot switch 310 to the cover 100.

The operation knob 314 is inserted into the opening 104, and the foot switch stub shafts 330 are inserted into the foot switch axis holes 334 of the cover l GO. Then, the brush plate 350 is fixed to the cover 100. The bnush plate stub shafts 376 are inserted into the brush plate axis holes 380 (see Figure 4B) of the cover 100. The second locking parts 358 of the brush plate 350 contact the first locking parts 318 of the foot switch 310 with the brush plate fixed. The coil spring 200 is inserted into the receptor 210 of the brush plate 350.

P5 1 5943GB 1 1 Finally, the base plate 150 is fixed to the cover 100. The fixation of the base plate 150 Is accomplished by inserting the stub shafts 152 into the first axis holes 154, and by inserting the stub shafts 156 into the second axis holes 158, respectively. The coil spring 200 is pressed into contact with the front end of the base plate 150, so as to bias the liront end of the base plate 150 for rotation in the direction of the arrow B (see Figure 3) and the rear end of the base plate Is biased by stoppers 164. As structured and assembled, the base plate 150 maintains a level position with respect to the surface to be cleaned.

Referring to Figures 4A and 4B, the brush plate support ribs 384, the foot switch support ribs 336, the first stub shafts 152, and the second base plate support ribs 157 each have a slope S. The slope S facilitates the smooth insertion of the stub shafts 152, 156, 330, and 376 into the corresponding axis holes 154, 158, 334, and 380 while the base plate fi, xng Relit 300 (see Figure 3) Is fixed to the cover 100.

Referring to Figure 5, the two stub shafts 156 correspond to the first axis holes 154. The suction port 176 is formed between the stub shafts 156. The sanction port 176 fluidly communicates with the suction duct 108 (see Figure 3). The rear end of the base plate 150 is provided with the mount protruding upward by the reference. Both ends of the mount 160 are provided with a base plate stopper 164 restraining, the base plate 150 from rotating in the direction B over a predetermined angle. Preferably, the mount 160 serves as the bottom plate stoppers 164. but it Is possible to use a separate member for each bottom plate stopper. If the base plate 150 rotates In the direction B over the predetermined angle, the base plate stoppers 164 contact the terminal ends ofthe brush plate support ribs 384 formed at the rear end 102 ofthe cover 100 (see Figure 3), and thus the base plate is restrained from rotating further in the direction B. P5 1 5943CB 12 Figure 6 illustrates the foot switch 310 in association with the brush plate 350. Referring to Figure 6, each first locking part 318 is rotatable through a predetermined angular range by the operation knob 314, and between first and second positions P1 and P2. The first position P1 refers to the position of that first locking part 318 when the foot switch 310 is restrained from further rotation in the direction C. The hoot switch 310 is restrained from rotating further in the direction C because the second stopper 328 (see Figure 3) contacts the suction duct 108. The second position P2 refers to the position ofthat first locking part 318 when the foot switch 310 is restrained from further rotation in the other direction D. The foot switch 310 is restrained from rotating further in the other direction D because the first stopper 324 contacts the cover 100. Each second locking part 358 includes a first contact part 360 contacting the associated first locking part 318 when that first locking part is at the first position Pl, and a second contact part 362 contacting that first locking part when that first locking part is at the second position P2. The second contact part 362 Is above the first contact part 360, so that the end of that Fiat locking part 318 which is in contact with the first contact part, contacts the second contact part when that first locking part moves prom the first position P1 to the second position P2. That first locking part 318 presses downwards onto the associated second locking part 358, so that the brush plate 350 rotates downwardly around the brush plate stub shafts 376.

Figure 7 illustrates the wheel shaft 420 fixed to the wheel-receiving part of the cover 100.

Rcf'emng to Figure 7, the outer circumference of one end of the wheel shaft 420 is provided with a locking projection 424. A complementary locking recess 414 is formed on the inner side of the adjacent wheel shaft hole 410. As shaped and configured above, the extension tube connector 500 Is inserted into the rear end of the cover 100, and the wheels 418 are fixed in the wheel receiving part 400. Then, the wheel shaft 420 is inserted into the wheel shaft holes 410 formed in the cover 100 and into the axis holes of the extension tube connector 500 (see Figure 3), thus P5 1 5943GB 13 rotatably fixing the extension tube connector and the wheels to the cover. The locking projector 424 of the wheel shaft 420 is coupled to the locking recess 414 of the adjacent wheel shaft hole 410 ofthe cover 100. With this simple locking suucure, the wheels 418 and the extension tube connector 500 are rotatably connected to the nozzle unit. Thus, the assembly of the nozzle Cubit is improved and the number ofthe parts is reduced.

As seen in Figures 8A and 8B, the base plate 150 is rotatable in a first (rotation) mode or is fixed in a second (stationary) mode with respect to the cover 100. While cleaning a surface such as a carpet, a user operates the vacuum cleaner in the rotation mode because the base plate 150 is not in close contact with that surface since the rear end of the nozzle unit is spaced from the surface.

Accordingly, the user selects the rotation mode to obtain close contact of the base plate 150 with the surface. The base plate 150 rotates with respect to the cover 10() in the rotation mode, even if the rear end of the nozzle unit is spaced from the surface. In contrast, for a surface such as a floor, which may be scratched by direct contact with the base plate 15(), a gap must be maintained between the base plate I SO a Id the surface. In this case' a user operates the vacuum cleaner in the stationary mode, with the brush 372 extending downwardly loom the front end of the nozzle unit and with the front end of the nozzle unit being against the surface and the rear end of the nozzle unit being supported by the wheels 418.

Figure 8A illustrates the rotation mode of the base plate 150 with respect to the cover 100, and Figure 8B illustrates the stationary mode. Referring to Figure 8A, the second stopper 328 (see Figure 3) is biased by the suction duct 108 and restrained from rotating in the direction C (see Figure 6). The Grst locking parts 318 at the ends of the foot switch 310 contact the first contact parts 360 ofthe second locking parts 358 formed at the ends ofthe brush plate 350. The front end of the base plate 150 is biased downwardly by the coil spring 200, and the rear end is supported ' us 1 5943GB] 4 because of the contact of the stoppers 164 with the terminal ends of the brush plate support ribs 384. The front end of the brush plate 350 is biased upwardly by the coil spring 200, and the rear end is supported since the first contact parts 360 ofthe second locking parts 358 are supported by the first locking parts 318. s

When operating the vacuum cleaner in the rotation mode to clean a surface such as a floor, the user presses the rear end of the operation knob 314 and changes to the stationary mode. Still referring to Figures 8A and 8B, the first locking parts 318 rotate downwards around the stub shafts 330. The first locking parts 318 press the second locking parts 358 while moving from the first contact parts 360 ofthe second locking parts to the second contact parts 362. Thus, the brush plate 350 rotates downwards around the stub shafts 376 so that the brush 372 moves and protrudes downwards from under the base plate 150. The coil spring 200, which is disposed at the front end of the brush plate 350 and biases the brush plate upwardly, is compressed due to the moment transferred from the first locking parts 318. With the coil spring 200 compressed, the I 5 front end of the base plate 150 receives a larger downwards recovery force than in the rotation mode. Accordingly, the base plate 150 becomes stationary, since its front end is biased by the compressed coil spring 200 with a greater recovery force than in the rotation mode, and the rear end is fixed since the stoppers 164 are supported by the ends of the brush plate support ribs 384.

As a result, scratching of the floor is prevented in the stationary mode by the bias plate 150.

Figures 9A and 9B are views ofthe base plate 150 in the rotation mode. Figure 9A shows the rear end of the nozzle unit in complete contact with the surface to be cleaned. The base plate 150 is biased downwards by the coil spring 200 at the front end, and is supported at the rear end by the stoppers I G4 contacting the terminal ends of the brush plate support ribs 384. Thus, the base plate 150 is level with the surface to be cleaned.

P5 1 5943GR Figure 9B shows the rear end of the nozle unit spaced from the surface to be cleaned due to the rotation of the nozle unit through a predetermined angle. The force applied on the nozle unit by the user is transferred to the coil spring 200 via the cover 100, the foot switch 310, and the brush plate 350. Such a force is applied in a direction so as to compress the coil spring 200 downwardly. The force of the base plate 150 adhering to that surface by the suction force results in a moment in a clockwise direchion around the stub shafts 152 and 156. Such a moment compresses the coil spring 200 upwardly, as it is biased against the front end ofthc base plate 150.

Therefore, the force of the base plate 150 which compresses the coil spring 200 upwards is greater than the force which compresses the coil spring downwards, so that the base plate rotates in the clockwise direction and remains level with the surface to be cleaned. Even when the rear end of the nozle unit lifts away from the surface to be cleaned, due to the difference between the force direction caused by the user on the nozle unit and the movement direction of the nozle unit, the base plate 150 can maintain close contact with that surface; thus enhancing the cleaning 1 5 efficiency.

When the rear end of the nozle unit returns to its original position, after being separated from the surface to be cleaned, the base plate 150 is rotated in a coulterclockwse direction by the coil spring 200 being compressed downwards on the front end of the base plate. The base plate 150 rotates until the stoppers 164 contact the temminal ends ofthe brushplate support ribs 384, thereby returning to its original position, as shown in Figure 9A.

Thus, even if the rear end of the nozzle unit is spaced from the surface to be cleaned, the close contact with that surface Is maintained, thus enhancing the cleaning efficiency. Wllen cleaning a surface such as the floor, the user changes to the stationary mode. Then, a proper gap is P5 1 594lGB maintained between that surface and the base plate 150, to avoid scratching that surface. This is because the brush 372 moves and protrudes downwards from the base plate 150, and supports the front end ofthe nozzle unit, the rear end of which is supported by the wheels 418.

Accordingly, the parts of the nozzle unit can be assembled without requiring fastening means such as bolts, because each stub shaft and each axis hole is provided with corresponding slopes.

In addition, the absence ofthe fastening means reduces the number of required parts.

Claims

P5 1 5943GB 17 Claims 1. A nozzle unit for a vacuum cleaner, the nozzle

unit comprising: a cover; and a base plate rotatably connected to the cover, the base plate having a suction port through which dust is drawn in from a surface to be cleaned, the dust being drawn in by a suction force generated by a vacuum generator disposed in the body of the vacuum cleaner.
2. A nozzle runt as claimed in Elaine 1, further comprising a resilient member disposed between the base plate and the cover for biasing an end ol the base plate in a predetermined direction.
3. A nozzle unit as claimed in claim 1 or claim 2, further comprising a base plate stopper disposed on at least one ofthe base plate and the cover to limit rotation ofthe base plate.
4. A nozzle unit as claimed in claim 3, further comprising a base plate fixing tUlit disposed between the cover and the base plate for selectively fixing the base plate to the cover.
5. A nozzle unit as claimed in claim 4, wherein the base plate fixing unit composes: a foot switch rotatably disposed in the cover, and having an operation knob extending through an opening in the cover and a first locking part; and a brush plate rotatably disposed in the cover for rotation in association with the foot switch, and having a second locking part complementary to the first locking part for locking and unlocking the brush plate.

P5 1 5943 18
6. A noz.le unit as claimed in claim 5, further comprising a brush disposed on the brush plate, the brush protruding between the cover and the base plate according to the rotational position of the brush plate.
7. A nozzle unit as claimed in claim 5 or claim 6, further comprising foot switch support ribs formed on the cover at a predetermined spacing, each of said ribs having an axis hole connectable with a respective foot switch stub shaft ofthe foot switch, wherein at least one of each foot switch stub shaft and the associated brush plate support rib is provided with a slope to facilitate that foot switch stub shaft being inserted into the axis hole of the associated support rib.
8. A nozzle unit as claimed in any one of claims S to 7, further comprising brush plate support ribs formed on the cover at a predetermined spacing, each of said ribs having an axis hole connectable with a respective brush plate stub shaft ofthe brush plate, wherein at least one of each brush plate stub shaft and the associated brush plate support rib is provided with a slope to facilitate that brush plate stub shaft being inserted into the axis hole of the associated support rib.
9. A nozzle unit as claimed in any one of claims 1 to 8, further comprising: base plate stub shafts formed on at least one ofthe base plate and the cover; and base plate support ribs, each having an axis hole connectable with a respective base plate stub shaft, and base plate support ribs formed on at least one of the cover and the base plate to complement the base plate stub shafts, P5 1 5943GB 19 wherein at least one of each base plate stub shaft and the associated base plate support rib is provided with a slope to facilitate that base plate stub shaft being inserted into the axis hole of the associated support rib.
10. A vacuum cleaner nozzle unit substantially as hereinbefore described with reference to, and as illustrated by, Figures 2 to 9 of the drawings.

10. A nozzle unit as claimed in any one of claims 1 to 9, further comprising: a wheel and a wheel shaft; a wheel-receiving part formed at a rear of the cover for receiving the wheel, and having a shaft hole through which the wheel shaft is inserted; a locking projection formed on the wheel shaft; and a locking recess formed adjacent to the shaft hole to complement the locking projection so that the wheel shaft can be inserted into, and locked with, the shalt hole.

11. A nozzle unit for a vacuum cleaner, the nozzle isn't comprising: a cover; a base plate rotatably connected to the cover, the base pLatc having a suction port through which dust is drawn in from a surface to be cleaned, the dust being drawn in by a suction force generated by a vacuum generator disposed in the body of the vacuum cleaner, a foot switch rotatably disposed in the cover, and having an operation krob extending through an opening in the cover and a first locking part; a brush plate rotatably disposed in the cover to rotate in association Wi01 the foot switch, and having a second locking part complementary with the first locking part, for locking and unlocking the brush plate; and a brush associated with the brush plate, and protruding between the cover and the base plate according to the rotational position ofthe brush plate.

Psls943GB 20 12. A vacuum cleaner nozzle unit substantially as hereinbefore described with reference to, and as illustrated by, Figures 2 to 9 ofthe drawings.

P5 1 5943GB Amendments to the claims have been filed as follows 1. A nozzle unit for a vacuum cleaner, the nozzle unit comprising: a cover; a base plate rotatably connected to the cover, the base plate having a suction port through which dust is drawn in from a surface to be cleaned, the dust being drawn in by a suction force generated by a vacuum generator disposed in the body ofthe vacuum cleaner; and a base plate fixing unit disposed between the cover and the base plate for selectively fixing the base plate to the cover; wherein - I O - the baseplate fixg--unit comprises a foot switch rotatably disposed in the cover, and having an operation knob extending through an opening in the cover and a first locking part; and a brush plate rotatably disposed in the cover for rotation in association with the foot switch, and having a second locking part complementary to the first locking part for locking and unlocking the brush plate.

2. A nozzle unit as claimed in claim 1, further comprising a resilient member disposed between the base plate and the cover for biasing an end of the base plate in a predetermined direction. 2(}

3. A nozzle unit as claimed in claim l or claim 2, farther comprising a base plate stopper disposed on at least one ofthe base plate and the cover to limit rotation ofthe base plate.

4. A nozzle unit as claimed in any one of claims 1 to 3, further comprising a brush disposed on the brush plate, the brush protruding between the cover and the base plate according to the rotational position ofthe brush plate.

P5 1 5943GB 1 tJ 5. A nozzle unit as claimed in any one of claims I to 4, further comprising foot switch support ribs formed on the cover at a predetermined spacing, each of said ribs having an axis hole connectable with a respective foot switch stub shad of the foot switch, wherein at least one of each foot switch stub shaft and the associated brush plate support rib is provided with a slope to facilitate that foot switch stub shaft being inserted into the axis hole ofthe associated support rib.

6. A nozzle unit as claimed in any one of claims I to 5, further comprising brush plate support ribs formed on the cover at a predetermined spacing, each of said ribs having an axis hole connectable with a respective brush plate stub shaft ofthe brush plate, wherein at least one of each brush plate stub shaft and the associated brush plate support rib is provided with a slope to facilitate that brush plate stub shaft being inserted into the axis hole ofthe associated support rib.

7. A nozzle unit as claimed in any one of claims I to 6, further comprising: base plate stub shafts formed on at least one ofthe base plate and the cover; and base plate support ribs, each having an axis hole connectable with a respective base plate stub shaft, and base plate support ribs formed on at least one of the cover and the base plate to complement the base plate stub shafts, wherein at least one of each base plate stub shaft and the associated base plate support rib is provided with a slope to facilitate that base plate stub shaft being inserted into the axis hole of the associated support rib.

8. A nozzle unit as claimed in any one of claims I to 7, further composing: P5 1 5943GB a wheel and a wheel shall; a wheel-receiving part Conned at a rear ofthe cover for receiving the wheel, and having a shaft hole through which the wheel shaft is inserted; a locking projection formed on the wheel shaft; and S a locking recess formed adjacent to the shaft hole to complement the locking projection so that the whee] shaft can be inserted into, and locked with, the shaft hole.

9. A nozzle unit for a vacuum cleaner, the nozzle unit comprising: a cover; - a base plate rotatably connected to the cover, the base plate having a suction port through which dust is drawn in from a surface to be cleaned, the dust being drawn In by a suction force generated by a vacuum generator disposed in the body ofthe vacuum cleaner, a foot switch rotatably disposed in the cover, and having an operation knob extending through an opening in the cover and a first locking part; a brush plate rotatably disposed in the cover to rotate in association with the foot switch, and having a second locking part complementary with the first locking part, for locking and unlocking the brush plate; and a brush associated with the brush plate, and protruding between the cover and the base plate according to the rotational position ofthe brush plate.