Rotary agitator for providing oscillating anp cleaning action

Abstract

A rotary agitator for a cleaning apparatus includes a body having an axis of rotation and a zero degree pitch plane perpendicular to the axis of rotation. The rotary agitator also includes an agitation element carried on the body. The agitation element includes a first portion provided at a positive pitch angle relative to the zero degree pitch plane and a second portion provided at a negative pitch angle relative to the zero degree pitch plane.

Description

TECHNICAL FIELD

The present invention relates generally to the floor care equipment field and, more particularly, to a rotary agitator with an agitator element providing oscillating nap cleaning action, a floor care appliance equipped with such a rotary agitator and to a method of cleaning a carpet or rug.

BACKGROUND OF THE INVENTION

A vacuum cleaner is an electrically powered, mechanical appliance utilized for the dry removal of dust and loose dirt from carpets, rugs, fabrics and other surfaces. Vacuum cleaners have been widely utilized for years in domestic and industrial cleaning applications.

In operation, a pressure drop is utilized to force air entrained with loose dirt and dust into the nozzle of the vacuum cleaner. The dust and dirt laden air is then drawn through a bag or dirt cup which traps and retains the dirt. The air is then exhausted by electric fan through an additional filter to remove relatively fine particles. It is this fan that provides the air pressure drop or vacuum that provides the cleaning action.

The present invention relates to a rotary agitator for a floor cleaning apparatus such an upright vacuum cleaner, canister vacuum cleaner, handheld vacuum cleaner, an extractor or the like. The rotary agitator is equipped with one or more agitation elements adapted to sweep the nap of an underlying rug or carpet in an oscillating, side-to-side manner. This cleaning action functions to more efficiently and effectively loosen and expose dirt and debris embedded down in the nap of a rug or carpet to the suction airstream so that it may be quickly drawn into the vacuum cleaner. This results in better cleaning.

SUMMARY OF THE INVENTION

In accordance with the purposes of the present invention as described herein, a rotary agitator is particularly adapted to provide high efficiency, deep cleaning of dirt and debris from the nap of an underlying rug or carpet. The rotary agitator includes a body that has an axis of rotation and a zero degree pitch plane perpendicular to that axis of rotation. Further the rotary agitator has at least one agitation element having a first portion provided at a positive pitch angle relative to the zero degree pitch plane and a second portion provided at a negative pitch angle relative to the zero degree pitch plane.

The agitation element may comprise any number of different structures including but not limited to a series of bristle tufts, a wiper, a brush and a beater bar. The agitation element may be substantially continuous or even comprise an oscillating ring.

Stated another way, the rotary agitator of the present invention comprises a body including an axis of rotation and a zero degree pitch plane perpendicular to that axis of rotation. In addition, the rotary agitator includes at least one endless agitation element carried on the body and straddling the zero degree pitch plane. More specifically, the endless agitation element includes (a) a first portion extending in a first arc from the zero degree pitch plane to a first point a first distance in a first direction from that pitch plane and then back to the pitch plane and (b) a second portion extending in a second arc from the pitch plane to a second point a second distance in a second direction from the pitch plane and then back to the pitch plane. That first distance A may be between about 0.5 and 3.0 cm. Further, the second distance may be substantially equal to the first distance.

In accordance with another aspect of the present invention a method is provided for removing dirt and debris from the nap of a rug or carpet. The method comprises providing a rotary agitator with an oscillating agitation element that functions to push the nap in a side-to-side motion during rotation of the rotary agitator.

In accordance with yet another aspect of the present invention a floor cleaning apparatus is provided. That floor cleaning apparatus comprises a housing, a suction generator carried on the housing, a dirt collection vessel carried on the housing and the rotary agitator of the present invention.

In the following description there is shown and described several possible embodiments of the invention, simply by way of illustration of some of the modes best suited to carry out the invention. As it will be realized, the invention is capable of other different embodiments, and its several details are capable of modification in various, obvious aspects all without departing from the invention. Accordingly, the drawings and descriptions will be regarded as illustrative in nature and not as restrictive.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings incorporated in and forming a part of the specification, illustrate several aspects of the present invention, and together with the description serve to explain certain principles of the invention. In the drawings:

FIG. 1 is a perspective view of the rotary agitator of the present invention;

FIG. 2 a is a schematical elevational view illustrating the geometry of the agitation element carried on the agitator;

FIG. 2 b is a detailed perspective, schematical view illustrating the arcs formed by the agitation element;

FIGS. 3 a and 3b are schematical side elevational views illustrating how the rotary agitator functions to push or brush the nap of an underlying carpet from side-to-side;

FIG. 4 illustrates a vacuum cleaner equipped with the agitator of FIG. 1; and

FIGS. 5 a-5f illustrate several additional embodiments of the rotary agitator of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Reference is now made to FIG. 1 illustrating the rotary agitator 10 of the present invention. The rotary agitator 10 includes a body 12. In the illustrated embodiment the body 12 is cylindrical in shape but other shapes could be provided. The body 12 may be molded from plastic, machined or cast from metal such as aluminum or constructed from any other appropriate material. In the illustrated embodiment the body 12 carries an axle or stub shafts 14 that extend from each end. As best illustrated in FIG. 2 the body 12 also includes an axis of rotation 16 defined by the axle or stub shafts 14 and a zero degree pitch plane 18 perpendicular to the axis of rotation 16.

As also illustrated in FIGS. 1, 2a and 2b, at least one agitation element 20 is carried on the body 12 of the rotary agitator 10. The agitation element 20 may assume any appropriate form including but not limited to a wiper, a brush, a beater bar and a series of bristle tufts. Each element 20 may be molded as an integral part of or affixed to the agitator body 12. In the illustrated embodiment, each agitation element 20 is substantially continuous so as to be effectively endless. Further, each agitation element 20 straddles the zero degree pitch plane 18 so as to effectively form an oscillating ring as the agitator 10 is rotated (note particularly FIG. 2a) with respect to a fixed point on the surface being cleaned.

More specifically, each agitation element 20 has a first portion 22 provided at a positive pitch angle A₁ relative to the zero degree pitch plane 18 and a second portion 24 provided at a negative pitch angle A₂ relative to the pitch plane 18.

Described another way each endless agitation element 20 includes a first arc 26 extending from the pitch plane 18 to a first point 28 a first distance in a first direction from the pitch plane 18 and then back to the pitch plane (see FIG. 2b). Additionally, the agitation element 20 includes a second arc 30 extending from the pitch plane 18 to a second point 32 a second distance in a second direction from the pitch plane 18 and then back to the pitch plane. The distance between the first point 28 and the pitch plane 18 may be between about 0.5 and 3.0 cm. The second distance between the second point 32 and pitch plane 18 may be substantially equal to that first distance.

As the rotary agitator 10 rotates about the axis of rotation 16, the agitation elements 20 first push, brush or comb the nap of an underlying carpet being cleaned in a first direction toward the ends of the agitator (note action arrows D₁ in FIG. 3a). Pushing, brushing or combing nap in this direction occurs as the rotary agitator rotates through the first 180 degrees of its rotation.

As the rotary agitator 10 rotates through its second 180 degrees of rotation, the nap of the underlying rug or carpet being cleaned is pushed, brushed or combed in a second opposite direction toward the middle of the agitator (note action arrows D₂ in FIG. 3b) by the agitation elements 20.

As the rotary agitator 10 continues to rotate, the nap is brushed back and forth from side to side so as to insure that dirt and debris on two sides of the nap is not only loosened but also fully exposed to the suction airstream of the floor cleaning device to which the rotary agitator is attached. This differs from agitators of the prior art that incorporate agitation elements that only brush the nap to one side thereby laying the nap over to that one side and holding it there so as to trap dirt and debris underneath the nap. By avoiding this problem, the present invention insures more efficient and effective deep cleaning of the underlying rug or carpet.

A vacuum cleaner 50 incorporating a rotary agitator 10 of the present invention is illustrated in FIG. 4. The vacuum cleaner 50 includes a housing, generally designated by reference numeral 52, including a nozzle assembly 54 and a handle assembly 56. As is known in the art, the handle assembly 56 is pivotally connected to the nozzle assembly 54 to aid the operator in manipulating the vacuum cleaner 50 back and forth across the floor. Wheels (not shown) carried on the housing 52 allow the vacuum cleaner 50 to be moved smoothly across the floor. As illustrated, the nozzle assembly 54 is equipped with a nozzle inlet 58. The rotary agitator 10 is mounted for rotation on the nozzle assembly 54 across the nozzle inlet 58 by means of an end cap and bearing assembly 59 provided on each end of the agitator 10 in a manner well known in the art (see FIGS. 3a and 3b).

The housing 52 houses a suction generator 62 (i.e. a fan and motor assembly) and a dirt collector 64 having an internal dirt collection chamber. In one possible embodiment, the dirt collector 64 comprises a filter bag. In another possible embodiment the dirt collector 64 comprises a dirt cup. That dirt cup may be substantially cylindrical in shape and include a tangentially directed air inlet and an axially directed air outlet. Such a structural arrangement produces cyclonic airflow which helps separate dirt and debris from the airstream and increase cleaning efficiency.

The handle assembly 56 also includes a control stalk 68 and an actuator switch 66 for turning the vacuum cleaner 50 on and off and thereby driving the rotary agitator 10 and the suction generator 62.

In operation, the rotary agitator 10 efficiently brushes dirt and debris from the nap of an underlying carpet. By brushing the nap from side-to-side, dirt and debris on both sides of the nap is exposed to the vacuum airstream so that it may be more efficiently drawn into the vacuum cleaner (note agitation elements 20 aligned with suction inlets 67 in the nozzle assembly 54 as illustrated in FIG. 3a). This represents a significant improvement over prior art agitators that tend to brush nap to one side laying that nap over dirt and debris on that side and effectively shielding that dirt and debris from the vacuum airstream. Loosened dirt and debris is drawn into the dirt collector 64 through the suction inlets 67 by means of the suction generator 62. Dirt and debris is trapped in the dirt collector 64 and the now clean air is directed over the motor of the suction generator 62 before being exhausted into the environment through the exhaust vent 70.

The foregoing description of a preferred embodiment of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. Obvious modifications or variations are possible in light of the above teachings. For example, while the illustrated embodiment in FIG. 4 is an upright vacuum cleaner 50, the present invention also relates to and includes canister and handheld vacuum cleaners as well as extractors. Further, while the illustrated embodiment is a “clean air” system with a suction generator 62 downstream from the dirt collector 64, the present invention also includes “dirty air” systems where the suction generator is located upstream of the dirt collector. Further, while the illustrated vacuum cleaner 50 includes one rotary agitator 10, it could include two or more rotary agitators if desired.

It should also be appreciated that the agitator 10 may also take the form of other embodiments as illustrated in FIGS. 5a-5e. In FIG. 5a, the agitator 10 includes a series of separate and parallel cleaning rings 80 for agitation elements. In FIG. 5b, the agitation element is a single, coiled element 82 that extends around and along the length of the agitator 10. All portions of the element 82 angle in the same direction with respect to plane 18 but the amount of the included angle varies to produce an oscillation as the agitator 10 rotates. In FIG. 5c, the agitator 10 includes agitation elements comprising a series of separate and alternating cleaning rings 84.

In FIG. 5d, the agitator 10 includes two sets of separate cleaning rings 86, 88. The first set of rings 86 are on a first side of the centerline CL of the agitator 10 and are angled in a first direction. The second set of rings 88 are on a second side of the centerline CL and are angled in a second direction. The number of rings in each set match and the angles of inclination are equivalent so that all forces are balanced and the nozzle is steady as the agitator 10 rotates. In FIG. 5e two separate coils 90, 92 are provided with one on each side of the centerline CL of the agitator 10. The coils 90, 92 are mirror images of each other. In FIG. 5f, an agitator 10 is illustrated incorporating multiple oscillating elements 94 having varying angles with respect to the pitch plane 18 mirrored about the center line CL.

The embodiments were chosen and described to provide the best illustration of the principles of the invention and its practical application to thereby enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the invention as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly, legally and equitably entitled. The drawings and preferred embodiments do not and are not intended to limit the ordinary meaning of the claims and their fair and broad interpretation in any way.

Claims

1. A rotary agitator, comprising: a body including an axis of rotation and a zero degree pitch plane perpendicular to said axis of rotation; and at least one agitation element having a first portion provided at a positive pitch angle relative to said zero degree pitch plane and a second portion provided at a negative pitch angle relative to said zero degree pitch plane.

2. The rotary agitator of claim 1, wherein said at least one agitation element is a series of bristle tufts.

3. The rotary agitator of claim 1, wherein said at least one agitation element is a wiper.

4. The rotary agitator of claim 1, wherein said at least one agitation element is a brush.

5. The rotary agitator of claim 1, wherein said at least one agitation element is a beater bar.

6. The rotary agitator of claim 1, wherein said at least one agitation element is selected from a group consisting essentially of a series of bristle tufts, a wiper, a brush, a beater bar, a molded rib and combinations thereof.

7. The rotary agitator of claims 1, wherein said at least one agitation element is substantially continuous.

8. The rotary agitator of claims 1, wherein said at least one agitation element is an oscillating ring.

9. A rotary agitator, comprising: a body including an axis of rotation and a zero degree pitch plane perpendicular to said axis of rotation; and at least one endless agitation element carried on said body and straddling said zero degree pitch plane.

10. The rotary agitator of claim 9 wherein said at least one endless agitation element includes (a) a first arc extending from said zero degree pitch plane to a first point a first distance in a first direction from said zero degree pitch plane and then back to said zero degree pitch plane and (b) a second arc extending from said zero degree pitch plane to a second point a second distance in a second direction from said zero degree pitch plane and then back to said zero degree pitch plane.

11. The rotary agitator of claim 10, wherein said first distance A is between about 0.5 and 3.0 cm.

12. The rotary agitator of claim 11 wherein said second distance is substantially equal to said first distance.

13. A method of removing dirt and debris from nap of a rug or carpet, comprising: providing a rotary agitator with at least one oscillating agitation element that functions to push the nap in a side-to-side motion during rotation of said rotary agitator.

14. A floor cleaning apparatus, comprising: a housing; a suction generator carried on said housing; a dirt collection vessel carried on said housing; and a rotary agitator carried on said housing, said rotary agitator having a body including an axis of rotation and a zero degree pitch plane perpendicular to said axis of rotation and at least one agitation element having a first portion provided at a positive pitch angle relative to said zero degree pitch plane and a second portion provided at a negative pitch angle relative to said zero degree pitch plane.

15. A floor cleaning apparatus, comprising: a housing; a suction generator carried on said housing; a dirt collection vessel carried on said housing; and a rotary agitator carried on said housing, said rotary agitator having a body including an axis of rotation and a zero degree pitch plane perpendicular to said axis of rotation and at least one endless agitation element carried on said body and straddling said zero degree pitch plane.