CLEANER HEAD FOR A VACUUM CLEANER

Abstract

A cleaner head for a vacuum cleaner includes a laser diode for illuminating debris located upon a region of a work surface located in front of the cleaner head with green light.

Claims

1. A cleaner head for a vacuum cleaner, the cleaner head comprising an optical system for illuminating debris upon a region of a work surface located in front of the cleaner head, the optical system comprising a laser diode which emits green light.

2. The cleaner head according to claim 1, wherein the cleaner head comprises opposing side walls, and the optical system is located adjacent one of the side walls of the cleaner head.

3. The cleaner head according to claim 2, wherein the cleaner head comprises a suction chamber, and the optical system is located between said one of the side walls and the suction chamber.

4. The cleaner head according to claim 2, wherein the cleaner head comprises an agitator, and the optical system is located to one side of the agitator.

5. The cleaner head according to claim 1, wherein the optical system is positioned so that the central axis of a light beam emitted by the optical system contacts a horizontal work surface upon which the cleaner head is located at an acute angle in the range from 0 to 10°.

6. The cleaner head according to claim 5, wherein the acute angle is in the range from 0 to 5°.

7. The cleaner head according to claim 1, wherein the optical system is positioned so that a light beam is emitted from the cleaner head at a height of less than 10 mm from a work surface upon which cleaner head is located.

8. The cleaner head according to claim 1, wherein the majority of the region of the work surface upon which debris is illuminated by the optical system is bounded by two planes each containing a respective side wall of the cleaner head.

9. The cleaner head according to claim 1, wherein the optical system comprises beam shaping means for receiving light emitted from the laser diode and directing the light towards the work surface such that, when the cleaner head is disposed upon a planar work surface, the optical system illuminates debris lying upon a region of the work surface which is in the shape of a sector.

10. The cleaner head according to claim 9, wherein the beam shaping means comprises a lens.

11. The cleaner head according to claim 9, wherein the central axis of the sector is aligned at an angle in the range from 35 to 65° to the front edge of the cleaner head.

12. A vacuum cleaner comprising: the cleaner head according to claim 1; and a suction source for drawing an airflow into the vacuum cleaner through the cleaner head.

13. The vacuum cleaner according to claim 12, in the form of a handheld vacuum cleaner.

14. The vacuum cleaner according to claim 12, in the form of a battery-powered vacuum cleaner.

15. The vacuum cleaner according to claim 12, comprising a controller for controlling the optical system.

16. The vacuum cleaner according to claim 15, wherein the controller is arranged to actuate the optical system when the suction source of the vacuum cleaner is switched on.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Preferred features of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

[0023] FIG. 1 is a perspective view of a vacuum cleaner;

[0024] FIG. 2 is a perspective of a cleaner head of the vacuum cleaner, illustrating a region of a work surface upon which debris is illuminated by an optical system of the cleaner head;

[0025] FIG. 3 is a side view of the cleaner head, with part of a side wall cut away to illustrate the components of the optical system;

[0026] FIG. 4 illustrates schematically a control system for the optical system; and

[0027] FIG. 5 is a graph illustrating the increase with time of the output optical power of the optical system from when the suction source is switched on.

DETAILED DESCRIPTION OF THE INVENTION

[0028] An embodiment of a vacuum cleaner is illustrated in FIG. 1. The vacuum cleaner 10 comprises a main body 12 which is attached by a wand assembly 14 to a cleaner head 16 through which a dirt-bearing airflow is drawn into the vacuum cleaner 10 by a suction source 18, which is generally a motor-driven fan unit. The vacuum cleaner 10 includes a separation system 20 for separating dirt and other debris from the airflow, a power source 22, in this embodiment a battery, for driving various components of the vacuum cleaner 10, including the suction source 18, and an air outlet 24.

[0029] The cleaner head 16 is illustrated in more detail in FIGS. 2 and 3. The cleaner head 16 comprises a casing 26 which defines opposing, generally parallel side walls 28, 30 of the cleaner head, and a suction chamber into which a dirt-bearing airflow is drawn into the cleaner head. The casing 26 may be formed from a number of different sections joined together. The suction chamber houses an agitator 32 for agitating dirt, dust or other debris from the work surface to become entrained within the airflow. The agitator 32 is in the form of a brush bar which is rotatable relative to the casing 26 about an axis which is collinear with the longitudinal axis of the agitator 32, and which in this embodiment is generally perpendicular to the side walls 28, 30 of the cleaner head 16. In this embodiment, the agitator 32 has a cylindrical shape, and includes rows of bristles 34 for engaging the work surface. A front portion of the agitator 32 is exposed by the casing 26. A front edge 36 of the cleaner head 16 is defined by the casing 26, the front edge 36 extending between, and generally perpendicular to, the side walls 26, 28. Alternatively, the front edge 36 may be defined by the agitator 32. The rotation of the agitator 32 is driven by a motor which is housed either inside the casing 26 or inside the agitator 32. The motor is arranged to rotate the agitator 32 in such a direction that the bristles 34 sweep dirt and debris rearwardly into the suction chamber. The suction chamber conveys the airflow air into a neck 38 of the cleaner head 16, within which the air is conveyed to an outlet 40 of the cleaner head 16.

[0030] The neck 38 includes a connector 42 for connecting the cleaner head 16 to the wand assembly 12, and electrical connectors 44 for connecting the motor and an optical system 46 of the cleaner head 16 to the power source 22 of the vacuum cleaner 10.

[0031] In FIGS. 2 and 3, the cleaner head 16 is illustrated as being located on a planar work surface W, such as a horizontal floor surface. The optical system 46 of the cleaner head 16 is located to one side of the agitator 32, within a housing 48 located between one of the side walls 28, 30 of the cleaner head 16 and the agitator 32. The optical system 46 is arranged to emit light through a window 49 of the housing 48 so as to illuminate debris lying upon a region 50 of the work surface located in front of the cleaner head 16. The optical system 46 comprises a light source 52 for emitting light, and a lens 54 for receiving the emitted light and for directing a light beam towards the work surface. The light source 52 and the lens 54 may be mounted in a module connected to the housing 48. In this embodiment, the light source 52 is a laser diode. A suitable laser diode is an Osram PLT5 510 green laser diode, which has a maximum optical output power of 10 mW at 25° C., and which emits green light at a wavelength of 515 nm. With reference also to FIG. 4, the light source 52 is connected to a controller 56 mounted in the cleaner head 16, preferably within the housing 48. The controller 56 is connected by one or more wires to one or more of the electrical connectors 44 located on the neck 38. When the neck 38 is connected to the wand assembly 14, wires within the wand assembly 14 connect the electrical connectors 44 to a controller 58 located in the main body 12 of the vacuum cleaner 10.

[0032] With reference to FIG. 3, the optical system 46 emits a light beam B, in this embodiment a beam of green light, towards the work surface. The beam B is preferably relatively shallow, having a vertical beam spread a1 which is less than 5°. The optical system 46 is positioned within the housing 48 so that the central axis A of the light beam B contacts the work surface W at an acute angle a2 in the range from 0 to 10°, more preferably in the range from 0 to 5°, and in this embodiment at an angle of 2°. The optical system 46 is positioned so that it is close to the work surface, and preferably so that the light beam B is emitted from the cleaner head 16 at a height of less than 10 mm, more preferably less than 5 mm, from the work surface.

[0033] Returning to FIG. 2, the optical system 46 is positioned within the housing 48, and the lens 54 is shaped, so as to direct the light beam towards the work surface W such that a region 50 of the work surface upon which debris is illuminated is in the shape of a sector. The sector has two radii R1, R2 which bound the sector, and which define a central angle Z1 of the sector. The central angle Z1 is preferably in the range from 70 to 110°.

[0034] The central axis A, located angularly midway between the two radii R1, R2 is preferably aligned at an angle Z2 to the direction D of forward movement of the cleaner head 16 over the work surface W, which direction D is generally parallel to the side walls 26, 28 and perpendicular to the front edge 36 of the cleaner head 16. The angle Z2 is preferably in the range from 25° to 45°, and in this embodiment is 35°. The central axis is thus aligned at an angle which is preferably in the range from 35 to 65°, and in this embodiment is 45°, to the front edge 36 of the cleaner head 16.

[0035] Each of the radii R1, R2 is longer than the maximum width of the cleaner head 16 so as to illuminate debris located upon regions of the work surface lying on either side of the path of forward movement of the cleaner head, which in this embodiment is located between the two planes containing the side walls 26, 28 of the cleaner head 16. To illuminate debris upon a region of the work surface W which is immediately in front of the cleaner head 16, the radius R1 is aligned at a relatively small angle, preferably less than 20°, more preferably less than 10°, to the front edge 36 of the cleaner head 16. The other radius R2 is preferably aligned at an obtuse angle to the front edge 36 of the cleaner head 16 so as to illuminate debris upon a region of the work surface lying outside of the path of forward movement of the cleaner head 16.

[0036] The optical system 46 is activated when the suction source 18 of the vacuum cleaner 10 is switched on by the user. The controller 58 of the vacuum cleaner 10 supplies power to the controller 56 of the cleaner head 16, which controls the supply of power to the light source 52 of the optical system so as to control the output optical power of the light source 52. Whilst the controller 56 may control the power supplied to the light source so that the output optical power is at a maximum, in this embodiment 10 mW, immediately after the suction source 18 is switched on, in this embodiment, the controller 56 controls the power supplied to the light source so that the output optical power increases gradually to the maximum over a period of time from when the suction source 18 is switched on. This can reduce power consumption at the start of a cleaning process, and reduce the risk that the user being exposed to the full output optical power of the light source 52 whilst the user may still being in the process of positioning the cleaner head 16 for the start of the cleaning process. With reference to FIG. 5, this period of time is preferably less than a few seconds, and in this embodiment is 0.25 sec.

[0037] The controller 58 is arranged to stop supplying power to the controller 56 when the suction source 18 is switched off by the user, or when the battery is exhausted, which in turn causes the light source 52 to become turned off.

[0038] The controller 56 may also vary the output optical power of the light source 52 away from the maximum during the cleaning process. As illustrated in FIG. 4, the cleaner head 16 may comprise a sensor 60 for monitoring a condition of the cleaner head 16, and for outputting a signal to the controller 56 depending on the monitored condition, in response to which the controller 56 may vary the output optical power of the light source 52. For example, the sensor 60 may be arranged to detect the pressure within the suction cavity or the neck of the cleaner head 16, and the controller 56 may be arranged to reduce, or suspend, the supply of power to the optical system 46 depending on a signal received from the sensor 60 which is indicative of the detected pressure. For example, the pressure within the cleaner head 16 can vary if the cleaner head 16 is lifted from the work surface, for example to reposition the cleaner head 16 on the work surface or during movement of the vacuum cleaner 10 to a different part of a room or other environment, and the output optical power of the light source 52 can be reduced whilst the cleaner head 16 is spaced from the work surface. When the signal received from the sensor 60 indicates that the cleaner head 16 has returned to a work surface, the controller 56 increases the power supplied to the optical system 46 so that the output optical power of the light source 52 returns to the maximum value. As another example, the sensor 60 may be arranged to detect the orientation of the cleaner head 16, which can also provide an indication that the cleaner head 16 has been lifted from the work surface.