US2915774A - Turbine drive surface cleaner with integral generator - Google Patents

Description

Dec. 8, 1959 K. A. DARROW TURBINE DRIVE SURFACE CLEANER WITH INTEGRAL GENERATOR Filed May 20, 1957 Inventor H/s Attorney.

TURBINE DRIVE SURFACE CLEANER WITH INTEGRAL GENERATOR Kenneth A. Darrow, Sprakers, N.Y., assignor to General Electric Company, a corporation of New York Application May 20, 1957, Serial No. 660,133

3 Claims. (Cl. 15-324) This invention relates to a turbine driven surface cleaner and, more particularly, to a turbine driven surface cleaner incorporating electrical power generation means therein to provide illumination of the surface to be cleaned.

Surface cleaners, generally referred to as vacuum cleaners, usually comprise a vacuum and/or rotating brush assembly which may be moved about surfaces such as floors, rugs, carpets, and the like in order to remove what may be called loose dirt or foreign particles of relatively small size. These cleaners may be categorized in two groups, the standard or upright, and the tank type.

The upright vacuum cleaner is designed with the drive motor and the brush and/or vacuum assembly as one unit to be moved about the surface to be cleaned. This arrangement, due to the size and weight involved proved to be quite awkward and unwieldy to the average operator for proper usage, and the general size of the unit prevented the operator from moving the unit into small spaces such as under tables and chairs and the like, and other areas of low overhead.

The tank type vacuum cleaner includes a generally portable electric motor driven vacuum pump which is connected, by means of a flexible tube, to a suitable small vacuum nozzle or tool. This type of tool is easily maneuvered into the small and low overhead spaces not readily entered by the upright cleaner. However, in comparison, it is found that the upright cleaner employing a brush together with vacuum conditions is superior to a tank type cleaner utilizing a vacuum nozzle only. The resulthas been that in several instances a rotating brush has been incorporated in the tool or nozzle of the tank type cleaner, with the brush being driven by a small air turbine in the tool. With the air turbine being driven by a vacuum pump in the tank, the smallness and compactness of the tool is preserved and areas normally inaccessible to the upright cleaner are retained as accessible to the tank type cleaner with a combined rotating brush and vacuum tool. While satisfactory cleaning may be accomplished with this tool, it has been found the aforementioned areas are darkened and poorly lighted which not only increases the difliculty of cleaning but also prevents the normal inspection an average operator would conduct.

In order to provide some illumination means on the tank type cleaner tool, it then becomes necessary to supply power from the normal domestic source or from the motor and pump assembly through the wand, lever, or handle in the operators hand and thence to an illumination means on the tool. This requires the passage of high voltage current through the handle in the operators hands with the inherent danger of electrical shock. Furthermore, where such handle or lever may be composed of sections of various length, such an illumination means requires suitable interchangeable electrical connections for each section of the wand. Therefore, where the normal operating procedure for vacuum cleaners includes the operators moving the tool about while remaining United States Patent 2,9 l 5,7 74 Patented Dec. 8, 1959 in a standing position, it may be appreciated that the results of the cleaning process in the aforementioned darkened areas is not or may not readily be perceivable to the operator at the time of cleaning. The usual fastidious operator, to prevent disappointment at discovering some dirt after the cleaning process is accomplished, is generally required to use additional lighting equipment or more cleaning than is necessary, or to stoop and bend in such a way that these darkened areas can be inspected more thoroughly from different angles of vision.

It is an object of this invention to provide lighting means on a rug or carpet and the like surface cleaner.

It is another object of this invention to provide lighting means on a rug cleaner which does not utilize any electrical connection passing through the hands of the operator.

It is a further object of this invention to provide lighting means on a rug cleaner which derives its power from an electrical generator in the cleaner nozzle or tool.

This invention contemplates the employment of a rotating brush for cleaning purposes which is driven by a radial inflow turbine. The motor drive and vacuum pump are separate from the rug tool and create low pressure conditions at the turbine inlet. Air from without the tool is drawn through the turbine, for rotation thereof, and thence through a tube to the motor and pump assembly. The rotating turbine not only serves to rotate the cleaning brush, but also drives a small generator to supply power for a forwardly directed light on the tool.

These and other features and advantages will be better understood when taken in connection with the following descriptin together with the accompanying drawing.

The drawing discloses a cross-sectional view of a rug tool of the preferred form of this invention.

Referring now to the drawing, there is shown a rug cleaning tool 1 having a casing or housing 2 comprising a relatively low circular and cup-shaped configuration which facilitates maneuvering the tool into low overhead spaces. Casing 2 contains a counter bore opening 3 in the outer surface in order to position a vertical hollow shaft 4. Shaft 4 is affixed to casing 2 by means of a flange 5 spaced from one end of the shaft which abuts the undersurface of the counterbore 3 and permits one end of the shaft 4 to project through the opening 3 in casing 2. Thereafter, a suitable engaging means such as a thread nut 6 is assembled on shaft 4 to abut the outer or upper surface of the counter bore and maintain shaft 4 in its vertical position. For the purposes of a smooth and pleasing appearance, a cap 7 is utilized to cover the counter bore opening. A radial inflow turbine wheel 8 which comprises a pair of separate spaced apart and curved plates 9 having vanes or blades 10 therebetween is horizontally and rotatably motlnted by means of a bearing 11 on shaft 4. Bearing 11 may be of the ball or roller type and lubricated by any suitable means well known in the prior art. In one form of this invention, as disclosed in the drawing, bearing 11 is a sleeve bearing of the lubricant impregnated type and for purposes of assuring lubrication for extended periods of time, a supply of lubricant is provided in a wick 12 in the hollow shaft 4. Shaft 4 contains one or more openings 13 through which lubricant from wick 12 may flow to hearing 11.

A radial inflow turbine may be described as one wherein the flow medium enters the vanes or blades at the periphery of the wheel to flow through the wheel and exhaust at the axis. The spaced apart plates 9 of wheel 8 of this invention define such a flow passage 14 of small annular cross-section at the periphery of turbine 8 through which air flows radially and horizontally into the wheel 8 and then curves downwardly to exhaust at a large annular opening 15 in a direction degrees from that of entry. In order to complete the defined passage into and out of casing 2, casing 2 has suitably disposed therein a series of openings or nozzles 16 spaced peripherally about opening 14 and communicating externally of easing 2.

To provide a flow of air through turbine 8, casing 2 is connected by a hollow tubular handle 17 to a source of vacuum, not shown. It should be noted that the handle 17 may be employed as a lever by which an operator may move tool 1 into the proper places, and that a flexible tube may be connected to this handle and to the vacuum source.

In the operation of this invention as thus far described, the vacuum source creates a low pressure area in the casing 2, thus causing air at the exterior of the casing 2, which is under a high relative pressure, to flow through opening 16 and through the aforementioned flow passage in the turbine 3. Vanes 19 in the turbine 8 are disposed to react to the air flow for rotation of the turbine wheel. A movement of air at a relatively high velocity through a small opening is accompanied by some degree of sound and it is desirable, therefore, to place suitable sound filters or barriers 18 over openings 16.

Turbine 8 includes a hub portion 19 having integral therewith a pulley or belt drive 20. This assembly is rotatably maintained on shaft 4 by means of a screw 2?; which passes through pulley 21} to engage shaft 4. Turbine 8 is designed in such a manner that at operating speeds the air fiow exerts a lifting force thereon and thus limits extensive bearing requirements between screw head 22 and pulley 20. It is desirable, however, to provide a thrust washer or hearing 23 between pulley 20 and the head 22 of screw 21 for starting or other conditions of low speed.

The particular form of cleaning element employed in this invention is a brush 24 which is rotably supported in casing 2 to lie parallel with the surface to be cleaned. Brush 24 includes a suitable belt drive or pulley 25 lying in a vertical plane rotated 90 degrees from the horizontal plane of pulley 26 on shaft 4.

A suitable flexible member such as a belt 26 is positioned on and between pulleys 2t} and 25 such that rotation of the turbine wheel 3 and pulley 20 in the horizontal plane rotates pulley 25 in the vertical plane. It should be apparent that this invention contemplates other forms of driving means between the turbine 3 and the brush 24 such as gear drives, chain drives, and the like.

In order to provide for the proper maintenance, cleaning, or inspection of the drive assembly, casing 2 has associated therewith a bottom cover plate 27 which may be removable or hinged to casing 2 by various means such as being pivotable at hinge 28 and suitably latched. A slot or opening 3% is provided in cover 27 to conform to both the length and diameter of the brush 24 in order to provide a proper area of exposed brush for cleaning and at the same time limiting any undue leakage of air between the brush 24 and the opening 30.

This invention has provided, in the description thus far, a highly efficient and compact rug or surface cleaner which is easily maneuverable into spaces with low overhead, for example, under furniture such as tables, chairs and the like. As heretofore mentioned, these particular areas are generally exposed to little if any illumination, and the darkness associated therewith contributes greatly to the cleaning and inspection problem. This invention, while providing a rug tool which makes these areas readily accessible also provides lighting suitable for these areas.

In the drawing power generation means are provided 1n tool 1 as associated with the rotation of turbine 8. Power generation means 31 comprises an electrical generator which includes iron pole pieces 32 afiixed to the casing 2 to surround the hub 19 on shaft 4. Suitable copper coils 33 are wound on pole pieces 32 to provide the stator of an electrical generator. A permanent magnet rotor 34 is alfixed to the hub 19 to be rotable therewith within the encircling stator. Current is then generated in the stator coils and supplied by means of lead 35 to a lamp or light 36. The lamp 36 may be a single bulb or a series of bulbs disposed on casing 2 to provide proper lighting. It has been found that lamps of approximately 5 watts input supplies satisfactory illumination for domestic cleaning purposes. With the generator operating at varying speeds such that the power output fluctuates, constant dimming of the light source would be objectionable. In the invention as disclosed, the generator includes the special feature of a relatively constant output voltage with varying operating speeds. In this respect the pole pieces 32 are of such a dimension that the iron therein becomes magnetically saturated at a low generator r.p.m. of approximately /3 to /2 of the normal operating speed. With this arrangement the output voltage of the generator is essentialiy constant, giving, in turn, a constant or uniform illumination on the surface to be cleaned. By providing the power means in the tool itself, there is thus eliminated the necessity of passing current through the hands of the operator, in the wand or lever, with the inherent danger of electrical shock to the operator, and where the lever or wand is composed of a series of sections, adaptable for shortening the length of the wand or changing to another tool, the necessity of numerous electrical connections are also eliminated.

This invention provides a combination surface cleaning, turbine driven tool not only easily maneuvered into specific areas of low overhead such as under tables, chairs, and other furniture, but also provides an electrically safe and efiicient lighting source for these areas.

It should be further noted that for additional maneuverability of the tool, one or more suitable wheels or rollers and the like may be provided on casing 2. A wheel or roller facilitates the control of the tool by supplying proper leverage to maintain correct loading or force being applied to press brush 24 against the surface to be cleaned.

While modifications of this invention and variations of apparatus that may be employed within the scope of the invention have not been described, the invention is intended to include all such as may be embraced Within the following claims.

What I claim as new and desire to secure by Letters Patent of the United States is:

i. In a surface cleaner, the combination comprising a casing, a shaft affixed to said casing, a radial inflow turbine having a hub thereon and rotatably mounted on said shaft, a rotatable brush mounted in said casing and adapted to contact the surface to be cleaned, drive means connecting said turbine to said brush for rotation thereof, electrical generator stator coils disposed in said casing to surround a portion of said turbine hub, a permanent magnet rotor aifixed to said hub for rotation within the said stator coils for the generation of electrical power, and a light source associated with said casing and connected to said generator stator coils to supply illumination for the surface to be cleaned.

2. In a tank type surface cleaner, the combination comprising a casing, 21 vertical shaft affixed to said casing, a radial inflow turbine having a hub thereon and rotatably mounted on said shaft, a rotatable brush mounted in said casing and adapted to contact the surface to be cleaned, a belt drive connecting said turbine to said brush for rotation thereof, electrical generator stator coils disposed in said casing to surround a portion of said turbine hub, a permanent magnet rotor affixed to said hub for rotation within the said stator coils for the generation of electrical power, and a light source associated with said casing and connected to said generator stator coils to supply illumination for the surface to be cleaned,

said stator coils being further characterized by having iron cores becoming magnetically saturated at turbine speeds substantially less than normal operating speeds, whereby a substantially constant voltage is supplied to said light source for normal cleaning turbine speeds.

3. In a tank type surface cleaner, the combination comprising a casing, a radial inflow turbine mounted in said casing, a series of nozzles disposed in said casing and communicating exteriorly of said casing to provide a flow of air to said turbine when the pressure within the casing is reduced, 21 sound filter operatively connected with said nozzles, a brush rotatably mounted in said casing and adapted to contact the surface to be cleaned, a belt drive connecting said turbine and said brush for rotation thereof, electrical power generation means driven with said turbine, and a light source on said casing utilizing current from said generation means to supply illumination for the surface to be cleaned.

References Cited in the file of this patent UNITED STATES PATENTS 1,607,562 Potter Nov. 16, 1926 1,695,794 Becker Dec. 18, 1928 2,248,390 Schaad July 8, 1941 2,281,858 Pierce May 5, 1942 2,683,276 Olsen July 13, 1954 2,769,997 Sheahan Nov. 13, 1956

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