Electric vacuum brush for vacuum cleaners

Abstract

An electric vacuum brush for vacuum cleaners has a vacuum head having a brush roller chamber through which suction air can flow, and a roller brush mounted to rotate in the brush roller chamber and driven by an electric motor. The vacuum head has a working width that is measured at the outside edges, crosswise to the working direction. The brush roller chamber has an opening at the bottom, delimited by parallel vacuum motor edges, which extends essentially over the working width of the brush roller chamber. The electric motor has a power consumption, measured at motor angle, of a maximum of 80 watts, and the vacuum head has a working width of more than 320 mm.

Description

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention relates to an electric vacuum brush for vacuum cleaners, which has a vacuum head having a brush roller chamber through which suction air can flow, and a roller brush mounted to rotate in the brush roller chamber, and driven by an electric motor. The vacuum head has a working width that is measured at the outside edges, transverse to the working direction. The brush roller chamber has an opening at the bottom, delimited by parallel vacuum mouth edges, which extends substantially over the working width of the brush roller chamber.

[0004] 2. The Prior Art

[0005] Commercially available electric vacuum brushes for household vacuum cleaners possess a working width between 280 mm and 350 mm. In the case of a working width between 280 mm and 300 mm, motors whose electric power consumption lies between 30 watts and 60 watts when the motor is idling are used as the drive unit. Furthermore, battery-operated electric vacuum brushes are known, the working width of which also lies in the indicated range between 280 mm and 300 mm. These motors, too, have a power consumption of approximately 30 watts when idling. With an increasing working width of the electric vacuum brush, more powerful motors are used to drive the brush roller. Commercially available electric vacuum brushes having a working width between 300 and 350 mm are equipped with universal motors whose power consumption lies in the range between 100 and 150 watts when the motor is idling. Finally, for the commercial sector, electric vacuum brushes having a working width of more than 400 mm are used, which are equipped with high-power universal motors having a power consumption, measured when the motor is idling, of 200 watts and up.

[0006] FIG. 1 shows the specific power consumption of commercially available electric vacuum brushes. The rated power pursuant to European Standard N 60335 of the electric motor driving the brush roller is plotted as a function of the working width of the electric vacuum brush. The rated power pursuant to EN 60335 is indicated on the label of each motor. This rated power is the power consumption of the motor in idle. In the working field shown in FIG. 1, three different ranges can be seen. Narrow electric vacuum brushes for household vacuum cleaners fall into working range A; these are equipped with permanent magnet motors or configured as battery-operated devices. Broad electric vacuum brushes having universal motors as the drive unit for the brush roller, also for household vacuum cleaners, fall into working range B. Range C is reserved for electric vacuum brushes for commercial use.

[0007] In the case of vacuum cleaner heads without rotating, driven brush rollers, for household vacuum cleaners, energy-efficient vacuuming is possible if the vacuum cleaner head is configured with a relatively large working width between 350 mm and 500 mm as described in EP 1 228 732 A2. By means of the configuration of the slide plate on the underside, particularly by means of the dimensions of the opening on the bottom, configured as a vacuum mouth, and the configuration of the vacuum mouth edges, the vacuum cleaner head can be designed so that the air volume, calculated as the product of the air stream and the partial vacuum, does not change, or changes only slightly, with an increasing working width. At a predetermined air volume, a larger floor surface can be cleaned as the working width increases.

[0008] There is a fundamental need to reduce the energy consumption of electric devices. The manufacturers of vacuum cleaners are optimizing the power consumption of the vacuum fans. The vacuum cleaner heads must be coordinated with the vacuum fans so that satisfactory results can be achieved with the overall system that consists of the vacuum fan and the vacuum cleaner head, both with regard to function and with regard to the energy demand. The energy consumption for driving a brush roller of an electric vacuum brush has always been ignored, until now, when considering the energy consumption of the system as a whole.

SUMMARY OF THE INVENTION

[0009] It is an object of the present invention to provide an electric vacuum brush with which large areas can be effectively cleaned, at the lowest possible energy consumption.

[0010] This object is accomplished, according to the invention, with an electric vacuum brush having the structure and purpose as indicated above, by means of combining a power consumption of the electric motor, measured at motor idle, of a maximum of 80 watts, and a working width of the vacuum head of more than 320 mm. “Power consumption” is the rated power indicated on the label of an electric motor, pursuant to European Standard EN 60335.

BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Other objects and features of the present invention will become apparent from the following detailed description considered in connection with the accompanying drawings. It should be understood, however, that the drawings are designed for the purpose of illustration only and not as a definition of the limits of the invention.

[0012] In the drawings:

[0013] FIG. 1 is a graph plotting power consumption versus working width of the vacuum head of commercially available electric vacuum brushes;

[0014] FIG. 2 is a graph plotting power consumption versus working width of the electric vacuum brush according to the invention in comparison to the prior art;

[0015] FIG. 3 is an exploded view of the electric vacuum brush according to the invention, in a top view;

[0016] FIG. 4 is the section A-A through the object of FIG. 3; and

[0017] FIG. 5 is a view from the bottom of the electric vacuum brush shown in FIG. 3.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0018] FIG. 2 shows the working range according to the invention, in comparison with the state of the art as explained above. The rated power of the motor that drives the brush rollers is plotted over the working width of the vacuum head. The working range according to the invention is characterized by the field D. The working ranges A, B, and C were already explained above, in the discussion of FIG. 1.

[0019] By means of the teaching according to the invention, it is provided that the power consumption of the electric motor driving the brush roller, measured at idle, is not allowed to exceed 80 watts even in the case of wide electric vacuum brushes whose working width is greater than 320 mm. It is true that the power required for driving the brush roller is dependent on the length of the brush roller and therefore on the working width of the electric vacuum brush, but the power required can also be influenced by other factors. These factors include the type and arrangement of the equipment of the brush roller, the distance of the bristles connected with the brush roller from the floor, and other design measures, e.g. the mounting of the brush rollers and the like.

[0020] According to the invention, the working width and the maximum power consumption of the electric motor that can be tolerated are predetermined as target values. The predetermined target values can be achieved by means of design measures as well as the selection of the motor. Preferably, a permanent magnet motor is used as the motor. In the technical implementation of the teaching according to the invention, a person skilled in the art can use known measures guided by the principles according to the invention.

[0021] According to a preferred embodiment of the invention, the vacuum head has a working width between 340 mm and 460 mm. Furthermore, it is preferred that the electric power consumption of the electric motor in idle is less than 60 watts.

[0022] FIGS. 3 to 5 show an embodiment used merely as an example of the structure of the electric vacuum brush according to the invention. The electric vacuum brush shown in FIGS. 3 to 5 is intended for household vacuum cleaners. The electric vacuum brush consists of a vacuum head 1, a brush roller 3 equipped with bristles 2 in spiral shape, which is arranged in a brush roller chamber 4 of the vacuum head, which chamber is open towards the bottom, and driven by an electric motor 5, and an outlet connector 6 that is mounted so as to tip or pivot, having a tube-shaped end for a connection to a vacuum tube connected with a household vacuum cleaner.

[0023] Vacuum head 1 is made up of a lower housing part 7 and an upper housing part 8. On the inside of the lower housing part 7, ridges 9 are formed, which separate a flow space from the installation space 10 for electric motor 5 and an installation space 11 for the electrical devices 12. Installation space 10 for electric motor 5 and installation space 11 for electrical devices 12 are arranged on both sides of an outlet channel that expands to become the roller chamber. A shell 13 is set onto ridges 9 of lower housing part 7, which shell encapsulates installation space 10 for electric motor 5 as well as installation space 11 for electrical devices 12, and forms the flow space within vacuum head 1. It is evident from FIG. 5 that vacuum head 1 has a working width W, measured at the outside edges, crosswise to the working direction, and that brush roller chamber 4 has an opening 15 at the bottom, delimited by parallel vacuum mouth edges 14, 14′, which extends essentially over working width W of brush roller chamber 4.

[0024] Although only at least one embodiment of the present invention has been shown and described, it is to be understood that many changes and modifications may be made thereunto without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. An electric vacuum brush for a vacuum cleaner comprising: (a) a vacuum head having a brush roller chamber through which suction air can flow; (b) a roller brush rotatably mounted in said brush roller chamber; and (c) an electric motor for driving said roller brush; wherein said vacuum head has a working width measured at outside edges of said vacuum head transverse to a working direction; wherein said brush roller chamber has a bottom with an opening defined by parallel vacuum mouth edges of said brush roller chamber and extending substantially over said working width; and wherein said electric motor has a maximum power consumption of 80 watts measured at motor idle and said working width of said vacuum head exceeds 320 mm.

2. The electric vacuum brush according to claim 1, wherein said electric motor is a permanent magnet motor.

3. The electric vacuum brush according to claim 1, wherein said vacuum head has a working width of 340 mm to 460 mm.

4. The electric vacuum brush according to claim 1, wherein the electric power consumption of said electric motor is less than 60 watts at idle.

5. A method of designing an electric vacuum brush for a vacuum cleaner comprising the steps of: (a) providing a vacuum head having a brush roller chamber through which suction air can flow, a roller brush rotatably mounted in the brush roller chamber, and an electric motor for driving the roller brush, said vacuum head having a working width measured at outside edges of said vacuum head transverse to a working direction, said brush roller chamber having a bottom with an opening defined by parallel vacuum mouth edges of said brush roller chamber and extending substantially over said working width; (b) limiting power consumption of the electric motor at motor idle to a maximum of 80 watts; and (c) fashioning the vacuum head so that the working width exceeds 320 mm.