BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a battery powered extractor according to the concepts of the present invention;
FIG. 2 is a front elevational view thereof;
FIG. 3 is a left side elevational view thereof;
FIG. 4 is a bottom perspective view of a base of the extractor;
FIG. 5 is a top perspective view of the base depicted in FIG. 4 with the cover removed to show further details of the extractor;
FIG. 6 is a perspective view of a handle of the extractor with the rear cover removed to show further details of the extractor;
FIG. 7 is a side elevational view similar to FIG. 8;
FIG. 8 is an enlarged partially fragmented perspective view of the handle depicting details of a switch according to the concepts of the present invention;
FIG. 9 is a graph showing battery energy as a function of time when an extractor simultaneously operating an agitator motor and vacuum motor;
FIG. 10 is a graph similar to FIG. 9 showing operation of an extractor with only the vacuum motor activated;
FIG. 11 is a graph similar to FIG. 9 showing alternating separate operation of an agitator motor and a vacuum motor for 30 second intervals; and
FIG. 12 is a graph similar to FIG. 11 where the agitator motor was operated for a 15 second interval while the vacuum motor was operated for a 5 second interval.
DETAILED DESCRIPTION OF THE INVENTION
An extractor according to one form or preferred embodiment of the present invention is generally indicated by the number 10 in the accompanying drawings. The preferred extractor is an upright style extractor 10 having a surface engaging portion or foot 12 with a handle portion 14 pivotally attached to the foot 12 for propelling the extractor 10 over a surface.
Referring now to FIG. 4, foot 12 is formed of a main frame 15 and a hood or cover 16 (FIG. 1) that are fastened together in any suitable fashion. Wheels 17 may be provided on frame 15 to help move the foot 12 on the surface. A suction nozzle 18 is mounted on a leading edge of foot 12 and depends downwardly from frame 15 to apply suction near the surface. A transparent suction nozzle cover 20 extends upwardly from suction nozzle 18 and defines a plenum that leads to a recovery conduit 23 (FIG. 5) through which soiled cleaning liquid is channeled to a recovery tank 25, as described more completely below. Suction nozzle cover 20 is received in a recess in the top of the hood 16.
Frame 15 defines an opening 24 in its lower surface 26 behind suction nozzle 18. A dispenser, generally indicated by the number 30, is provided within opening 24 to dispense cleaning solution on to the surface. Dispenser 30 may be of any known type capable of depositing fluid on the surface. In the example shown in FIG. 6, dispenser 30 includes plural openings 32 spaced widthwise along the foot 12 and within the confines of opening 24. Openings 32 are recessed within a laterally extending channel 34 that helps to disperse the cleaning solution laterally. Cleaning solution is supplied to the dispenser 30 from a supply tank 37, which may be mounted on handle 14 (FIG. 1), via a supply tube 39 (FIG. 5). Mounting supply tank 37 above foot 12 allows cleaning solution to be gravity fed to dispenser 30. To maximize the potential energy of the cleaning solution within the supply tank 37, supply tank 37 may be mounted at an upper portion 39 of handle 37. To prevent the supply tank 37 from interfering with the user's operation of handle 14, a grip 72 may extend above supply tank 37.
An agitator, generally indicated by the number 35, may be mounted near dispenser 30, as shown, to help disperse the cleaning solution on the surface. Agitator 35 may include brushes 36 to work the cleaning solution into the surface and dislodge dirt or other debris on or within the surface. Any known agitator brush may be used. In the example shown, brushes 36 are arranged helically on a shaft 38. Shaft 38 is journalled on frame 15 so that it is freely rotatable within opening 24. Rotation of brush shaft 38 is controlled by operation of an agitator motor 40 (FIG. 5) that is coupled to the shaft 38 as by a belt 42 or other known coupler.
Cleaning solution and any dirt on the surface is recovered by applying a vacuum to the recovery tank 25, which in turn creates suction at suction nozzle 18 in a manner well known in the art. Recovered cleaning solution and dirt flow from suction nozzle 18 to recovery tank 25 via recovery conduit 23, which may include a flexible portion 23A that extends through the joint 45 between foot 12 and handle 14 (FIG. 5).
As best shown in FIGS. 3 and 7, recovery tank 25 is releasably attached to handle 14 and may be removed to discard the recovered dirty cleaning solution. To that end, handle 14 may be provided with a recovery tank support, generally indicated by the number 50, having a lower ledge 52 on which the recovery tank 25 rests. A lower face plate 54 may be attached to handle 14 to cover lower ledge 52 and partially support recovery tank 25. A latch assembly 55 may be provided on handle 14 at the upper extremity of recovery tank 25 to grasp the upper extremity of recovery tank 25 and selectively lock it in place. In the example shown, latch assembly 55 is mounted on a brace 56 that attaches to a center support 58 (FIG. 6) within handle 14 above recovery tank 25.
Center support 58 also acts as a mounting for a vacuum motor, generally indicated by the number 60 that selectively applies a vacuum to recovery tank 25 to recover the cleaning solution, as described above. As best shown in FIG. 6, vacuum motor 60 may include a vacuum fan or blower 62 that is connected to the recovery tank by a vacuum nozzle 64 and draws working air through the recovery tank 25.
Power for the vacuum motor 60 and agitator motor 40 is supplied by one or more batteries, generally indicated by the number 65 in FIGS. 6 and 7. The battery 65 is electrically connected in a selective fashion by a switch, generally indicated by the number 70. Switch 70 may be of any known type. Switch 70 limits operation of the agitator motor 40 and vacuum motor 60 so that only one may operate at a time to conserve the battery power and extend the useful life of the battery 65. As depicted in the graphs attached as FIGS. 9-12, experiments were performed to test the useful life of the battery 65 under different operating conditions. FIG. 9 depicts an example of a typical prior art extractor arrangement operating with both the agitator and vacuum motors running. The useful life under these conditions was approximately 9 minutes. Operating the vacuum motor continuously, as depicted in FIG. 10 resulted in a useful life of approximately 12 minutes. Staggering operation of the agitator motor and vacuum motor was found to produce a dramatic increase in the useful life. For example, as depicted in FIG. 11, operating the agitator motor and vacuum motor in alternating 30 second cycles extended the useful life of the batteries to approximately 26 minutes. Even greater extension of the useful life was achieved by operating the agitator motor for a 15 second cycle and the vacuum motor for a 5 second cycle in alternating fashion. As depicted in FIG. 12, under these operating conditions, a useful life of approximately 40 minutes was achieved. The graphs and operating conditions described above are provided as examples and are not to be considered limiting. In general, to extend the useful life of battery 65, extractor 10 forces the user to alternately use the agitator motor 40 and vacuum motor 60 by preventing simultaneous operation of both motors.
To that end switch 70 may include three positions. In a first position, switch 70 electrically connects the battery 65 to agitator motor 40. In a second position, switch 70 electrically connects battery 65 to vacuum motor 60. And, in a third position, switch 70 disconnects battery 65 so that extractor 10 is in an “off” condition. As best shown in FIG. 8, switch 70 may be mounted on a grip portion 72 of handle 14 and located for ease of operation. For example, switch 70 may be placed on an upper surface 74 of grip portion 72 so that the user may operated switch 70 with their thumb while maintaining their grasp on handle 14. To encourage the user to operate extractor 10 in an alternating fashion, switch 70 is arranged with the first position i.e. agitation or “scrub” mode being forward and the second position i.e. vacuum or “pick up” mode being rearward, and the third position i.e. “off” mode located between the first and second positions. As shown in FIG. 3, a trigger 75 may be provided on the underside of handle 14 to open a valve (not shown) to dispense cleaning solution from supply tank 37 as described above. In a preferred method of operation, cleaning solution is dispensed by dispenser 30 on to the surface, and switch 70 is moved to a first position to agitate the dispensed cleaning solution by operation of agitator 35 powered by agitator motor 40. This operation may be performed with a forward stroke of extractor 10. Then after agitation, switch 70 is moved to the second position to activate vacuum motor 60 and recover the dispensed cleaning solution from the surface and collect it in recovery tank 25. This operation may be performed in a return stroke of extractor 10 so that an alternating operation of agitator motor 40 and vacuum motor 60 on a stroke basis is achieved. This stroke based operation of the agitator and vacuum motors would closely approximate the conditions observed in the examples depicted in FIGS. 11 and 12 maximizing battery life.
The present invention has been described by way of example using a preferred embodiment. Modifications to and variations of the preferred embodiment will be readily apparent to one of skill in the art upon reading the above description and reviewing the appended drawings. In view of the above, it is intended that the present invention not be limited by the preceding detailed description of one form or preferred embodiment of the present invention, but rather include all modifications and variations of the disclosed embodiment within the spirit and scope of the present invention.
Patent Application
20080047093
