Vacuum cleaner device

Abstract

The present invention relates to a vacuum cleaner device (1) for operation on a floor area (F), comprising: a suction duct (7) and an actuator (9) arranged and configured to generate an underpressure in the suction duct (7) so that air is sucked into the suction duct (7), a temperature sensor (10) configured to sample an air temperature in the vicinity of the device (1), wherein said temperature sensor (10) is arranged in the suction duct (7) or adjacent an opening (6d) of the suction duct (7), and an analyzing unit (3) configured to detect a wet spot (W) on said floor area (F) using said sampled air temperature.

Claims

1. A vacuum cleaner device for operation on a floor area, comprising: a suction duct and an actuator arranged and configured to generate an underpressure in the suction duct so that air is sucked into the suction duct, a temperature sensor configured to sample an air temperature in the vicinity of the device, wherein said temperature sensor is arranged in the suction duct or adjacent an opening of the suction duct, and an analyzing unit configured to detect a wet spot on said floor area using said sampled air temperature, wherein the analyzing unit is configured to detect the presence of a wet spot on the floor area in case the sampled air temperature shows a predefined temperature drop over a predefined period of time or in case a slope of the sampled air temperature is negative and decreases below a predefined threshold, and wherein the temperature drop per period of time is larger than 0.2° C./s, and/or wherein the temperature drop per period of time is in the range from 0.4° C./s to 1° C./s.

2. The vacuum cleaner device according to claim 1, wherein the analyzing unit is further configured to at least one of: determine if the temperature drop is followed by an increase of the sampled temperature after passing of a pre-defined time span to confirm detection of the wet spot; determine if a relative humidity sampled by the vacuum cleaner device increases when the temperature drop occurs and/or decreases when said increase of the sampled temperature occurs to confirm detection of the wet spot; determine if a total temperature drop associated with the detected wet spot exceeds a pre-defined threshold to confirm detection of the wet spot; determine if a total relative humidity increase associated with the detected wet spot exceeds a pre-defined threshold to confirm detection of the wet spot.

3. The vacuum cleaner device according to claim 1, wherein the vacuum cleaner device comprises at least one relative humidity sensor configured to sample a relative humidity of the air in the vicinity of the vacuum cleaner device.

4. The vacuum cleaner device according to claim 3, wherein the analyzing unit is configured to detect a wet spot on said floor area using said sampled air temperature and said sampled relative humidity.

5. The vacuum cleaner device according to claim 4, wherein the analyzing unit is configured to detect the presence of a wet spot on the floor area in case the sampled air temperature shows a predefined temperature drop over a predefined period of time or a slope of the sampled temperatures is negative and decreases below a predefined threshold, and in case the relative humidity shows a predefined increase over a predefined period of time or a slope of the sampled relative humidity increases above a predefined threshold.

6. The vacuum cleaner device according to claim 1, wherein the device comprises a housing having a bottom wall configured to face said floor area upon operation of the vacuum cleaner device on said floor area, wherein the bottom wall comprises said opening, and wherein the housing comprises a lateral wall.

7. The vacuum cleaner device according to claim 1, wherein the suction duct comprises a constriction, wherein the temperature sensor is arranged in the constriction.

8. The vacuum cleaner device according to claim 6, wherein the temperature sensor is mounted to the bottom wall or to the lateral wall adjacent said opening.

9. The vacuum cleaner device according to claim 3, wherein the at least one relative humidity sensor is mounted to a bottom wall of a housing of the vacuum cleaner device or to a lateral wall of a housing of the vacuum cleaner device.

10. The vacuum cleaner device according to claim 3, wherein the at least one relative humidity sensor is arranged in the suction duct.

11. The vacuum cleaner device according to claim 10, wherein the at least one relative humidity sensor is arranged in the suction duct downstream a filter for filtering particles that is arranged in the suction duct.

12. The vacuum cleaner device according to claim 1, wherein the vacuum cleaner device is a robotic vacuum cleaner device for autonomous operation on the floor area.

13. The vacuum cleaner device according to claim 12, wherein the vacuum cleaner device comprises a drive system that is configured to move the device.

14. The vacuum cleaner device according to claim 1, wherein when the vacuum cleaner device detects a wet spot, the vacuum cleaner device is configured to at least one of: stop, move around the wet spot, clean up the wet spot, store and/or transmit a location of the wet spot, output a warning signal.

15. The vacuum cleaner device according to claim 1, wherein the analyzing unit is configured to determine a size of a detected wet spot in a movement direction of the vacuum cleaner device using a velocity of the vacuum cleaner device in the movement direction, as well as a location of a beginning of the detected wet spot and a location of an end of the detected wet spot with respect to the movement direction.

16. The vacuum cleaner device according to claim 15, wherein the analyzing unit is configured to determine said location of a beginning of the detected wet spot as a location at which the analyzing unit determines one of: an onset of a drop of the sampled temperature; a negative slope of the sampled temperature, which slope is smaller than a predefined threshold; an onset of an increase of a sampled relative humidity; a positive slope of the sampled relative humidity, which slope is larger than a predefined threshold.

17. The vacuum cleaner device according to claim 15, wherein the analyzing unit is configured to determine said location of an end of the detected wet spot as a location at which the analyzing unit determines one of: an onset of an increase of the sampled temperature; a positive slope of the sampled temperature, which positive slope is larger than a predefined threshold; an onset of a decrease of the a sampled relative humidity; a negative slope of the sampled relative humidity, which slope is smaller than a predefined threshold.

18. The vacuum cleaner device according to claim 1, wherein the vacuum cleaner device comprises at least one further temperature sensor configured to sample an air temperature in the vicinity of the device, wherein the at least one further temperature sensor is arranged in a further suction duct of the vacuum cleaner device, or wherein the temperature sensor is arranged in a first branch of the suction duct and the at least one further temperature sensor is arranged in a second branch of the suction duct.

19. The vacuum cleaner device according to claim 18, wherein the analysing unit is configured to detect a wet spot on said floor area using said sampled air temperature sampled by the temperature sensor and said sampled air temperature sampled by the at least one further temperature sensor.

20. The vacuum cleaner device according to claim 18, wherein the analyzing unit is configured to determine a location and/or dimension of the wet spot using the sampled temperatures sampled by the temperature sensor and the at least one further temperature sensor.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Attention is now directed to the attached drawings, wherein like reference numerals or characters indicate corresponding or like components. In the drawings

(2) FIG. 1 shows a schematical cross-sectional view of an embodiment of a vacuum cleaner device according to the present invention comprising a temperature sensor arranged in a suction duct of the device;

(3) FIG. 2 shows a schematical cross sectional view of a further embodiment of a vacuum cleaner device according to the present invention comprising two separate suctions ducts, wherein a temperature sensor is arranged in each suction duct;

(4) FIG. 3 shows a schematical cross sectional view of a further embodiment of a vacuum cleaner device according to the present invention comprising a suction duct having two branches, wherein a temperature sensor is arranged in each branch of the suction duct;

(5) FIG. 4 shows a schematical cross-sectional view of an embodiment of a robotic vacuum cleaner device according to the present invention; and

(6) FIG. 5 shows experimental data, particularly a temperature signal of a temperature sensor that is arranged in the suction duct (denoted as tube) as well as a temperature signal of a temperature sensor that is arranged outside the suction duct on the head of the vacuum cleaner device, wherein the head has been moved over a wet spot;

(7) FIG. 6 shows a temperature signal of a temperature sensor that is arranged in the suction duct as well as a temperature signal of a temperature sensor that is arranged outside the suction duct on the head of the vacuum cleaner device, wherein the signals are shown for four passes of the head of the vacuum cleaner device over the wet spot;

(8) FIG. 7 shows a relative humidity signal of a relative humidity sensor that is arranged in the suction duct (denoted as tube) as well as a relative humidity signal of a relative humidity sensor that is arranged outside the suction duct on the head of the vacuum cleaner device, wherein the head has been moved over a wet spot;

(9) FIG. 8 shows a relative humidity signal of a relative humidity sensor that is arranged in the suction duct (denoted as tube) as well as a relative humidity signal of a relative humidity sensor that is arranged outside the suction duct on the head of the vacuum cleaner device, wherein the signals are shown for four passes of the head of the vacuum cleaner device over the wet spot;

(10) FIG. 9 shows the temperature signal of a temperature sensor arranged in the suction duct (denoted as tube) and the slope of the temperature signal when the head of vacuum cleaner devices passes over the wet spot;

(11) FIG. 10 shows a temperature signal of a temperature sensor that is arranged in the suction duct (denoted as tube) as well as the slope of the temperature signal, wherein the signal/slope is shown for four passes of the head of the vacuum cleaner device over the wet spot;

(12) FIG. 11 shows the relative humidity signal of a relative humidity sensor arranged in the suction duct (denoted as tube) and the slope of the relative humidity signal when the head of vacuum cleaner devices passes over the wet spot; and

(13) FIG. 12 shows a relative humidity signal of a relative humidity sensor that is arranged in the suction duct (denoted as tube) as well as the slope of the relative humidity signal, wherein the signal/slope is shown for four passes of the head of the vacuum cleaner device over the wet spot;

DETAILED DESCRIPTION

(14) FIG. 1 shows a vacuum cleaner device 1 for operation on a floor area F, wherein the device 1 comprises a suction duct 7 and an actuator 9 (e.g. a ventilator) that is configured to generate an underpressure in the suction duct 7 so that air is sucked into the suction duct 7. Further, the device 1 comprises a temperature sensor 10 configured to sample an air temperature in the vicinity of the device 1, wherein said temperature sensor 10 is arranged in the suction duct 7. Furthermore, the vacuum cleaner device 1 comprises an analyzing unit 3 configured to detect a wet spot W on said floor area F using said sampled air temperature.

(15) Particularly, the device 1 comprise a head 6 having a bottom wall 6c configured to face said floor area F upon operation of the device 1 on said floor area F. Further, the head 6 may comprise a circumferential lateral wall 6a extending from the bottom wall 6c. Alternatively, instead of arranging the temperature sensor 10 in the suction duct 7, the temperature sensor 10 can also be arranged on the lateral wall 6a or on the bottom wall 6c, particularly in proximity to the opening 6c of the suction duct 7 so that the temperature sensor 10 is arranged in a region that experiences a suction effect generated by the suction duct 7 and actuator 9.

(16) Particularly, for detecting a wet spot W, particularly when the head 6 of the vacuum cleaner 1 is moving on the floor area F, the analyzing unit 3 analyzes the current air temperatures sampled with the temperature sensor 10 and concludes detection of a wet spot W in case the sampled air temperature drops by a predefined amount within a pre-defined period of time.

(17) Furthermore, in addition, at least one relative humidity sensor 11 can be arranged in the suction duct 7 (or on the head 6), wherein the at least one relative humidity sensor 11 can be used to confirm detection of the wet spot W, since the sampled relative humidities show an increase when the head 6 approaches a wet spot W (see also experimental data described below). Furthermore, as described above, a beginning B and an end E of the wet spot W with respect to the movement direction D can be detected (e.g. for determining a size/diameter of the wet spot W).

(18) FIG. 2 shows a modification of the embodiment shown in FIG. 1, wherein here the vacuum cleaner device 1 comprises two suction ducts 7, 7a, starting from an associated opening 6d formed in the bottom wall 6c of the head 6, wherein a temperature sensor 10, 10a is arranged in each suction duct 7, 7a. Furthermore, a relative humidity sensor 11, 11a can be arranged in each suction duct 7, 7a, too, in order to improve detection of wet spots W. In the embodiment shown in FIG. 2, two temperature signals (and optionally relative humidity signals) can be used to determine the presence of a wet spot W as described above in conjunction with FIG. 1.

(19) Furthermore, FIG. 3 shows a further modification of the embodiment shown in FIG. 1, wherein here the suction duct 7 branches off and comprises two branches 7b, 7c, wherein each branch 7b, 7c ends at its respective opening 6d formed in the bottom wall 6c of the head 6. Also here, two temperature signals (and optionally relative humidity signals) can be used to determine the presence of a wet spot W as described above in conjunction with FIG. 1.

(20) Furthermore, FIG. 4 shows a further embodiment of a vacuum cleaner device 1 according to the present invention in form of a robotic vacuum cleaner device 1. As shown in FIG. 4 such a robotic device 1 can comprise a drive system 2 configured to move the device 1 autonomously on the floor area F, a temperature sensor 10 for sampling an air temperature in the vicinity of the device 1 (e.g. upon movement of the device 1 on the floor area F), and an analyzing unit 3 configured for detecting a wet spot W on said floor area F using said air temperature as an input, particularly when the device 1 approaches said wet spot W.

(21) For moving, the drive system 2 of the robotic device 1 can comprise rotatable wheels 20 via which the robotic device 20 is supported on the floor area F. For example, a first wheel 20 can be driven with a first motor 21 and—similarly—a second wheel can be independently driven with a second motor (not shown) of the drive system 2 which also allows steering of the device 1 in a simple manner. Other ways of steering and driving the device 1 can also be used.

(22) Further, the robotic device 1 can comprise an electronic control unit 4 to control the drive system 2, particularly the respective motor 20, so that the device 1 can move autonomously on said floor area F. The device 1 may further comprise a navigation system 5 for determining the current location (e.g. coordinates) of the robotic device 1 on the floor area F.

(23) The device 1 can further comprise a housing 6 having a bottom wall 6c configured to face said floor area F upon operation of the robotic device 1 on said floor area F.

(24) Further, the device 1 comprises a circumferential lateral wall 6a that also forms a front side 6b of the device when the device 1 moves in a movement direction D with the front side 6b ahead.

(25) In an embodiment, the temperature sensor 10 can be mounted to the bottom wall 6c or to the lateral wall 6a, particularly to the front side 6b (wherein the temperature sensor 10 is preferably arranged in proximity to the opening 6d, see below, so that the temperature sensor 10 is arranged in a region where a suction effect/air flow generated by the device 1 is present). Particularly, in order to provide better protection of the temperature sensor 10, the latter is arranged in a suction duct 7 of the device 1 which is shown in FIG. 4.

(26) Particularly, the suction duct 7 can extend from an opening 6d formed in the bottom wall 6c of the housing 6 and may extend from said opening 6d forming an intake to an outtake opening 6e. The duct 7 may comprise a constriction 70, wherein particularly the temperature sensor 10 is arranged in the constriction 70. Further, a filter 8 can be arranged in the suction duct 7 for filtering particles sucked into the suction duct 7 due to an underpressure generated by an actuator 9 (e.g. a ventilator) that can be arranged downstream the filter 8.

(27) Furthermore, besides the temperature sensor 10, the device 1 can comprise at least one or several (e.g. one to three) relative humidity sensors 11.

(28) Particularly, the at least one relative humidity sensor 11 can also be mounted to the bottom wall 6c or to the lateral wall 6a, particularly to the front side 6b, as shown in FIG. 4.

(29) In order to offer better protection, the at least one relative humidity sensor 11 can also be arranged in the suction duct 7, as also shown in FIG. 4, particularly, the at least one relative humidity sensor 11 can be arranged downstream the filter 8 and particularly upstream said actuator 9. In case the at least one relative humidity sensor 10 is arranged in the suction duct 7 it is less exposed to mechanical damage.

(30) Particularly, for detecting a wet spot W, e.g. in front of the device 1, when the device is moving in the movement direction D, the analyzing unit 3 analyzes the current air temperatures sampled with the temperature sensor 10 and concludes detection of a wet e.g. spot in case the sampled air temperature drops by a predefined amount within a pre-defined period of time. Alternatively, also the slope of the sampled temperature and particularly other quantities related to temperature and/or relative humidity discussed above can be used to detect a wet spot W.

(31) Particularly, the at least one relative humidity sensor 11 can be used to confirm detection of the wet spot W, since the sampled relative humidities show an increase when they approach the respective wet spot W (see also above).

(32) Particularly, when the vacuum cleaner device 1 detects a wet spot W, the device 1 is configured to at least one of: stop, move around the wet spot W, remove the wet spot W, store a location of the wet spot W in a data storage 30 of the robotic device 1, output a warning signal (e.g. acoustic and/or optical warning signal).

(33) Particularly, the device 1 allows a user to look up the location of the wet spot via an interface of the device (e.g. via a smart phone app) so that the user can find the wet spot even in case it has been removed by the device 1 for inspection.

(34) Furthermore, the FIGS. 5 to 12 show experimental data recorded with temperature and relative humidity sensors that are located in the suction duct 7 of a vacuum cleaner device or on the head 6 (e.g. lateral side 6a).

(35) Particularly, FIG. 5 shows a temperature signal of a temperature sensor that is arranged in the suction duct 7 (denoted as tube) as well as a temperature signal of a temperature sensor 10 that is arranged outside the suction duct 7 on the head 6 of the vacuum cleaner device 1, wherein the head 6 has been moved over a wet spot W. FIG. 5 clearly shows the increase in the sampled temperature for both sensor locations.

(36) Furthermore, FIG. 6 shows a temperature signal of a temperature sensor that is arranged in the suction duct 7 as well as a temperature signal of a temperature sensor that is arranged outside the suction duct 7 on the head 6 of the vacuum cleaner device 1, wherein the signals are shown for four passes of the head 6 of the vacuum cleaner device 1 over the wet spot W. Particularly, FIG. 6 demonstrates that a wet spot can also be detected when the device 1 is moving, since the respective signal shows a characteristic drop in case of a wet spot (here approx. at times 24:57, 25:06, 25:32, 25:49).

(37) Further, FIG. 7 shows a relative humidity signal of a relative humidity sensor 11 that is arranged in the suction duct 7 (denoted as tube) as well as a relative humidity signal of a relative humidity sensor 11 that is arranged outside the suction duct 7 on the head 6 of the vacuum cleaner device 1, wherein the head 6 has been moved over a wet spot. As can be seen from FIG. 7, the sampled relative humidity clearly increases for both sensor locations due to the wet spot.

(38) In addition, FIG. 8 shows the signals of FIG. 7 in case the head 6 passes over the wet spot (here four such passes).

(39) FIGS. 9 to 12 show further experimental data to show that also the slope of the temperature signal (i.e. the sampled temperature) of a temperature sensor 10 or the slope of the relative humidity signal (i.e. the sampled relative humidity) of a relative humidity sensor 11 is a suitable detection signal for wet spots. Here, the respective sensor 10, 11 is arranged in the suction duct 7 of a vacuum cleaner device 1 and the head 6 of the vacuum cleaner device 1 via which air is sucked into the suction duct 7 passes over the wet spot. FIG. 9 shows the temperature signal and its derivative with respect to time (i.e. the slope of the sampled temperature) for a single pass of the head 6 of the vacuum cleaner device 1 over the wet spot, while FIG. 10 shows four succeeding passes over the wet spot.

(40) FIGS. 11 and 12 show the same situation for the relative humidity signal of a relative humidity sensor 11 that is arranged in the suction duct 7. Also FIGS. 11 and 12 demonstrate that the relative humidity signal (sampled relative humidity) as well as the derivative of the relative humidity signal (i.e. the slope of the sampled relative humidity) can be used to detect wet spots.

(41) While a vacuum cleaner device has been shown and described above, this is exemplary only.

(42) The above-disclosed subject matter can also be applied with and adapted for other (e.g. robotic or manually operable) devices that perform various tasks, including cleaning, sweeping, polishing, lawn mowing, gardening etc.

(43) The vacuum cleaner devices disclosed herein have been described with exemplary reference to specific features and in a manner sufficient to enable persons of ordinary skill in the art to readily reduce any of the embodiments of the present invention to practice without undue experimentation and using conventional techniques. While preferred embodiments of the present invention have been described, so as to enable one of skill in the art to practice the present invention, the preceding description is intended to be exemplary only. Moreover, the embodiments and components thereof are exemplary.

(44) This description should not be used to limit the scope of the invention, which should be determined by reference to the following claims.