Title:
ROTATABLE BRUSH FOR CLEANING APPARATUS
United States Patent 3828387


Abstract:
A rotatable brush for cleaning apparatus is composed of a shaft supported for rotation within the apparatus. Attached to the shaft are a plurality of rows of bristles extending along the shaft in radially spaced relationship. The bristles are inclined relative to the axis of the shaft to permit maximum bristle length without increasing the overall diametrical dimension of the brush.



Inventors:
LIEBSCHER J
Application Number:
05/162207
Publication Date:
08/13/1974
Filing Date:
07/13/1971
Assignee:
LEIFHERT G KG,DT
Primary Class:
Other Classes:
15/41.1
International Classes:
A46B13/00; A47L11/33; (IPC1-7): A46B7/10; A46B1/00
Field of Search:
15/179-183,198,200,41-50,79
View Patent Images:
US Patent References:
0395362N/A
0271971N/A
0023526N/A



Foreign References:
GB409860A
Primary Examiner:
Feldman, Peter
Attorney, Agent or Firm:
Striker, Michael S.
Claims:
What is claimed as new and desired to be secured by Letters Patent is set forth in the appended claims

1. A rotatable brush for cleaning apparatus, particularly for carpet sweepers, comprising an elongated rotary member; and tufts of bristles projecting from said member and being arranged in a plurality of rows having a substantially sinusoidal configuration, all of said rows extending in substantial parallelism with one another, and the tufts in each of said rows being free of contact with the tufts in the respectively adjacent rows, each of said bristles being inclined to the axis of said member at an angle different from 90°, and the bristles in adjacent ones of said rows being inclined in mutually opposite directions.

2. A rotatable brush as defined in claim 1, each of said tufts having a free end; and wherein the free ends of the tufts in each of the respective rows are located in a common plane substantially parallel to said axis.

3. A rotatable brush as defined in claim 1, wherein said angle is substantially 40° to 80°.

4. A rotatable brush as defined in claim 3, wherein said angle is substantially 60°.

5. A rotatable brush as defined in claim 1, wherein said rows extend in a direction along said axis.

6. A rotatable brush as defined in claim 1, wherein at least some of said bristles are inclined in longitudinal direction of the respective row.

Description:
BACKGROUND OF THE INVENTION

The present invention relates in general to a rotatable brush for cleaning apparatus and more particularly to a rotatable brush for carpet cleaners.

It is known in cleaning apparatuses including a rotatable brush to arrange the bristles of the brush along the body of the brush shaft which is rotatable in the cleaning apparatus. In this type of rotatable brush it is particularly important to maintain a maximum length of the bristles without sacrificing the bending capability of the bristles. It is also important to maintain a sufficient bending resistance while at the same time keeping the bristles soft enough for maximum cleaning effect and to prevent mechanical destruction of the bristles or damage to textile floor coverings such as carpets. In known brushes, this requirement results in undesirable large overall diameters of the brush body and consequent increase in overall structural dimension of the cleaning apparatus which, of course, is undesirable.

Accordingly, it is the primary object of the present invention to provide a rotatable brush of the above type for cleaning apparatus particularly carpet cleaning apparatus which permits reduction in overall structural dimensions of the cleaning apparatus, while at the same time permitting optimum bristle length.

SUMMARY OF THE INVENTION

In the present invention the above object is accomplished by having the bristles arranged along the rotatable brush shaft in inclined position relative to the axis of the brush shaft. In this manner the relative stiffness of the brush along the entire length of the brush shaft can be varied within a wide range without increasing the overall diameter of the brush.

In known practice the bristles of the brush are normally arranged in rows of individual bunches of bristles which are attached to the rotatable shaft body of the brush for radial extension therefrom.

The tips of all the bristles at opposite ends of the brush shaft are preferably located in planes parallel to the axis of the shaft. By this, a substantially sturdy structure of the brush is obtained while at the same time assuring simultaneous floor contact of all of the bristles along the shaft.

In accordance with the present invention it is proposed that alternate rows of bristles along the rotatable shaft be inclined in opposite directions relative to the axis of the shaft and to each other to prevent possible side thrust by movement of the cleaning apparatus along the floor, particularly in the instance of light-weight cleaning apparatus, which otherwise would occur if the bristles were all inclined in the same direction. By arranging the bristles of adjacent rows in opposite inclined directions as disclosed herein, thrust forces in transverse direction to the movement of the cleaning apparatus will be self-eliminating. By practical experiment an angle of inclination of the bristles of the brush from between 40° to 80° has been found to be best suitable. The preferred angle of inclination is about 60° which has been found to be best suited to obtain maximum cleaning effect without any undue harm to the bristles or the floor covering.

Furthermore, in accordance with the present invention, the bristles of the present improved rotatable brush can be selectively arranged in rows parallel to the axis of the brush shaft or they may be arranged on the shaft along sinusoidal or helical paths.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a bottom view of a representative cleaning apparatus of the type herein referred to, incorporating one embodiment of an improved rotatable brush in accordance with the present invention;

FIG. 2 illustrates another embodiment of a rotatable brush for the cleaning apparatus shown in FIG. 1; and

FIG. 3 is still another embodiment of a rotatable brush for the cleaning apparatus shown in FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION

With reference to the drawing and particularly FIG. 1, there is illustrated a representative cleaning apparatus generally indicated at 10, such as a carpet cleaner, seen from the bottom thereof. The carpet cleaner 10, as will be understood, is only representative of the type of cleaning apparatus in which the improved rotatable brush of the present invention may be embodied. It will be further understood that the cleaning apparatus 10 may be equipped with a plurality of rotatable brushes 11 in any suitable known arrangement including such arrangement in which the bristles of adjacent brushes intermeshingly engage each other. The structure of the cleaning apparatus per se is considered to be irrelevant and forms no part of the present invention.

The schematically illustrated cleaning apparatus 10 is comprised of a housing 12 which is equipped inwardly of the thereof with opposite bearing support members 13. Bearing support members 13, in this instance, each rotatably support a pair of ground contact wheels 14 and in between them a rotatable brush 11 which is the primary subject of the present invention.

In known cleaning apparatus of this type in order to vary the height of the rotatable brush 11 relative to the floor surface either bearings 15 for the brush 11 or bearings 16 for the ground engaging wheels 14 may be adjustably supported on bearing support members 13. On the other hand, if no adjustment is required, all of the bearings may be stationary.

The rotatable brush 11 of the cleaning apparatus is comprised of a rigid rotatable brush shaft 17 which in the present instance is provided at both ends with axial bearing recesses 18 adapted to engage bearing members 15 projecting from the main bearing supports 13. Both ends of the brush shaft 17 in this instance provide increased diameter head portions 19 which are each disposed between a pair of ground engaging wheels 14 at each side of the cleaning apparatus 10 and in driving contact with the wheels. Thus, during rotation of the ground engaging wheels 14 by movement of the cleaning apparatus 10 across the floor surface brush 11 will be caused to rotate.

In the illustrated example of FIG. 1, the dirt and other contaminants picked up by the rotating brush 11 will normally be deposited in shallow containers 20 adjacent both sides of the brush 11. Containers 20 have movable flaps 21 for convenient removal of the dirt from the containers 20.

As illustrated in the embodiment of FIG. 1, the bristles 22 of brush 11 are arranged in a plurality of individual packs or bunches as is known. A plurality of bristle bunches are disposed along the brush shaft 17 substantially along the entire length thereof and in parallel rows 23, 24 circumferentially spaced from each other. In the embodiment of FIG. 1 the bristle rows 23, 24 as will be noted are disposed parallel to the axis of the brush shaft 17.

In order to maintain a minimum floor clearance between the brush 11 and the floor surface while at the same time maintaining the structural dimension of the cleaning apparatus as small as possible and to provide relative soft floor contact of the bristles 22, the bristles 22 in any one of the bristles rows 23, 24 are inclined at an angle less than 90° and in the same direction relative to this axis of the brush shaft 17. By this arrangement the effective length of the bristles can be advantageously increased in contrast to the arrangement in known rotatable brushes which have radially extending bristles. By suitable variation of the angle of inclination of the bristles any desirable effective length of the bristles can be selected for optimum cleaning effect while maintaining good bending characteristics of the bristles and thereby a relatively soft floor contact in accordance with the particular specific stiffness characteristic of the bristles.

In cleaning apparatus of particularly light-weight construction it is of further advantage to arrange the rows of bristles 23, 24 such that alternate rows are inclined in opposite directions relative to each other. By this arrangement possible side thrust forces against the rotating brush 11 will be effectively prevented since the occurring thrust forces of adjacent rows of bristles oppose each other.

It shall be mentioned here that any suitable number of rows of bristles 23, 24 may be arranged around the brush shaft 17 in accordance with the diameter of the brush shaft 17 and the size of the cleaning apparatus 10. However, an even number of rows of bristles is desirable for the reasons stated in the above.

In the embodiment of FIG. 2 the rotatable brush 25 is similarly composed of a substantially rigid brush shaft 17 having enlarged head portions 19 at both ends thereof. The bristles 22 of brush 25 are similarly grouped in individual bunches, as is customary, and which in this instance are arranged in parallel rows extending along sinusoidal paths from end to end of brush shaft 17.

The individual sinusoidally arranged rows 26, 27 of bristles 22 are parallel to each other and bristles 22 are similarly inclined in longitudinal direction at an angle less than 90° relative to the axis of the brush shaft 17. Here, likewise, the bristles of alternate rows of bristles may be inclined in opposite direction relative to each other to effectively counterbalance side thrust forces during rotation of the brush 25 over the floor surface.

In the embodiment of FIG. 3, the rotating brush 29 is similarly constructed of a shaft 17 supporting a plurality of parallel rows of bristles 30, 31. In this instance, the rows of bristles 30, 31 are disposed in spiral or helical fashion along the brush shaft 17 parallel to each other. Similarly, the bristles 22 of alternate rows 30, 31 are inclined in opposite directions relative to the axis of the brush shaft 17.

It will be obvious from the foregoing that the rows of bristles may be arranged in different manners than those illustrated and described, consideration only to be given to the fact that an even number of rows be employed so that always even numbers of rows of bristles are inclined in opposite directions to each other. Furthermore, it has been found to be of advantage to select the length of the bristles such that the tips at the ends of each row of bristles are located in a plane parallel to the axis of the rotatable brush shaft 17 to assure even ground contact of all of the bristles along the brush.

Preferably, and as determined by respective experiments, the angle of inclination of bristles 22 relative to the axis of the brush shaft 17 lies between 40° and 80° whereby a mean of 60° inclination has been found to be of particular advantage.

As previously mentioned, the illustrated embodiments represent only particular examples of the invention which, however, is not limited to these embodiments.

The invention readily lends itself to various modifications in detail and structure including brush shafts made of plastic material or any desirable metal. The rotatable brush may also be made of wire for variations in diameter and flexibility of the brush shaft. Obviously, the bearing arrangements and driving mechanism for the present improved rotatable brush are subject to similar modifications, although these arrangements form no part of the present invention.

As likewise mentioned before, the bristles of the brush of the present invention may be arranged on the brush shaft in other linear forms different from those shown and described herein or the bristles may be arranged along the brush shaft 17 at random without following any particular linear or curvilinear pattern. Additionally, individual bunches of bristles may be of different lengths as required for certain particular applications.

It will be understood that each of the elements described above in relation to the present improved rotatable brush construction may also find useful applications in other types of cleaning apparatuses differing from the types described herein.

Thus, while the invention has been illustrated and described as embodied in a known carpet cleaning apparatus, the invention is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit and characteristic of the present invention.

Without further analysis the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.