Vacuum-cleaning robot

Abstract

A self-propelled vacuum cleaner has a main housing having a bottom wall formed with an aperture, floor-engaging wheels on the main housing, and a drive in the main housing for rotating the wheels and advancing the main housing in a normal horizontal travel direction. A module housing projecting through the aperture forms a brush compartment defining a downward directed suction opening having relative to the direction a leading edge and a trailing edge. The module housing is supported in the main housing for limited vertical movement of the module housing relative to the main housing. A brush in the module housing is engageable through the opening with a floor beneath the opening, and a blower in the module housing having an intake connected via a duct to the brush compartment for aspirating air through the opening and past the brush into the module housing.

Claims

1. A self-propelled vacuum cleaner comprising: a main housing having a bottom wall formed with an aperture; floor-engaging wheels on the main housing rotatable for advancing the main housing in a normal horizontal travel direction; a module housing projecting through the aperture and forming a brush compartment defining a downward directed suction opening having relative to the direction a leading edge and a trailing edge, the module housing being limitedly vertically movable in the main housing relative to the main housing; a brush in the module housing engageable through the opening with a floor beneath the opening; a blower in the module housing having an intake; a duct connecting the intake to the brush compartment for aspirating air through the opening and past the brush into the module housing; structure forming an angled slide face at least 10 mm high at the leading edge; and a flexible lip extending downward from the module housing rearward in the direction from the trailing edge.

2. The self-propelled vacuum cleaner defined in claim 1, further comprising: springs supporting the module housing on the main housing.

3. The self-propelled vacuum cleaner defined in claim 1, further comprising: rollers or slides supporting the module housing on the floor.

4. The self-propelled vacuum cleaner defined in claim 1, wherein the module housing has a rigid bottom wall and the angled slide is unitarily formed on a thickened region of the bottom wall at the leading edge.

5. The self-propelled vacuum cleaner defined in claim 1, wherein the angled slide face forms a substantially planar ramp extending downward and rearward from the module housing relative to the travel direction.

6. The self-propelled vacuum cleaner defined in claim 1, wherein the slide face is made from an array of ribs and/or ridges.

7. The self-propelled vacuum cleaner defined in claim 1, wherein the trailing edge is formed as a ridged edge.

8. The self-propelled vacuum cleaner defined in claim 1, wherein the roller chamber is pivotally mounted and the suction-opening edge is molded on a bottom wall of the module housing.

9. The self-propelled vacuum cleaner defined in claim 8 wherein a pivot axis of the roller chamber is flush with a rotation axis of the cleaning roller.

Description

BRIEF DESCRIPTION OF THE DRAWING

(1) The above and other objects, features, and advantages will become more readily apparent from the following description, reference being made to the accompanying drawing in which:

(2) FIG. 1 is a schematic side view partly in section of a self-propelled vacuum cleaner;

(3) FIG. 1A is a detail view of the structure indicated at IA in FIG. 1;

(4) FIG. 2 is a schematic bottom view of the vacuum cleaner of FIG. 1; and

(5) FIG. 3 is a schematic bottom view of a further embodiment of the vacuum cleaner.

SPECIFIC DESCRIPTION OF THE INVENTION

(6) As seen in FIG. 1 a vacuum-cleaning robot according to the invention has a main housing 1, typically of injection-molded plastic holding a schematically illustrated controller 16 and drive 17, as well as a battery serving as power supply 19, antennas, and such.

(7) The generally planar rigid bottom wall of the main housing 1 carries two coaxial drive wheels 2 that are rotated by the drive 17 and that can be differentially rotated to steer the device. A ball-type caster 16 at the front end of the main housing bottom wall provides the third point of support, making the main housing 1 stable even on an uneven floor surface F.

(8) The main housing also holds a blower 18, structure including a duct 10 connected to the suction side of the blower 18 for drawing in air and separating dirt. The design of such a vacuum cleaner, which is also called a vacuum robot, has been known for a long time. The weight of the basic body of the vacuum robot is borne by the two driven wheels 2 and the support caster 15. Instead of a caster, this support can a slide.

(9) On the underside of the self-propelled vacuum cleaner there is a modular suction cleaning tool 3 that according to the invention includes a cylindrical roller chamber 5 holding a standard driven brush 6 and open downward at an elongated mouth opening 20 having parallel leading and trailing edges 8 and 13 extending perpendicular to a standard travel direction D. The leading edge 3 is formed by a thickened portion of the planar floor or bottom wall of the one-piece injected module housing 21 of the module 3, and having a lower face 7 that is planar and angled downward and back so as to form a smooth and gentle ramp. This angled face 7 is 10 mm high and forms an angle of at most 45 to the horizontal.

(10) The leading and trailing edges 8 and 13 are at the same level and lie below the plane of the floor of the module housing 21. In addition as shown in FIG. 1A, the periphery of the bottom wall of the module housing 21 has raised edges 22 that are supported on top of the bottom wall of the main housing 1 by compression springs 12 that allow the entire module 3 to be deflected upward into the housing 1.

(11) Rearward of the trailing edge 13 of the opening 20 is a downwardly projecting transverse lip 9 that is normally flexible and that primarily serves to prevent excessive air being drawn into the opening 20 by the blower 3 from behind.

(12) The wheels 2 and support caster 15 hold the main housing 1 at such a height that it can easily clear any irregularities in the floor F that are likely to be encountered. The mouth 20, however, opens at a significantly lower level set to be ideal for vacuuming a smooth floor, for instance of wood or tile and about 1-2 mm. If, however, the floor has, for example, a high pile, this will push the entire module 3 up into the housing 1, resetting the level of the mouth 20 where it is needed for vacuuming such a surface. Because of the vertically movable or pivotally movable mounting of the module 3, it automatically adjusts to floor conditions. It also ensures that the front suction-opening edge 8 during suctioning of smooth surfaces maintains a specified distance of preferably 1 to 2 mm from the floor.

(13) The vertically movable or pivotal support of the suction-cleaning tool is decoupled from the weight of the basic robot body. This ensures that the preassembled suction-cleaning module 3 moves upward freely or against a spring force when the vacuum robot for example is used on a high-pile floor covering and the basic robot body sinks relatively deeply into the pile because of its weight.

(14) The angled slide 7 in the embodiment is a rigid sliding surface on the planar bottom wall 4 of the module housing 21. In place of the sliding surface illustrated in FIGS. 1 and 2 the angled slide 4 can be formed by an array of ribs and/or ridges. The back edge 13 of the bottom-wall opening of the vacuum-cleaning tool is rigid. The flexible lip 9 mounted in the back then is only for additional sealing of the suction-cleaning tool 3 in the back.

(15) The cleaning roller 6 can be equipped with brushes 14 (FIG. 2 only or elastic lips that are helically arranged along the circumference of the cleaning roller. Independent of the flooring and the specific application the cleaning roller can also have soft pads, for example made from plush, felt or foam.

(16) In the embodiment of FIG. 3, the main housing 1 has a vertically movable or pivotal suction-cleaning tool 3 provided with rollers 11 that support it on the floor F. The rollers 11 ensure that the leading suction-opening edge 8 during vacuuming of a smooth floor maintains a defined spacing of preferably 1 to 2 mm from the floor surface. Instead of the rollers 11 other floor slides, ball-type rollers, or wheels that automatically align with the travel direction of the robot can be used.