DESCRIPTION OF THE PREFERRED EMBODIMENT

[0042] As seen in FIGS. 1 and 2 , the present invention comprises a cleaning device generally indicated by reference number 100 . Device 100 is adapted to utilize external supplies of electricity and water. A cord 17 is attached to an electrical outlet (not shown) and hose 18 is attached to a faucet or other water source (not shown) with a standard faucet adapter that is well known in the art. Cleaning chemicals are preferably added to water in hose 18 by a chemical injector at the point where the cleaning hose connects to the faucet. Injectors and other similar devices are well known in the art and they are commonly used to add cleaning chemicals to water in a predetermined proportion. The water and cleaning chemicals are mixed as they travel through hose 18 and device 100 to form a cleaning solution that is used to clean a carpet or material 50 . A wastewater line 19 is also provided for removing wastewater. Preferably cord 17 , hose 18 , and wastewater line 19 are 50 to 80 feet long.

[0043] A switch 15 is provided on a handle 16 to activate a 24 volt solenoid valve 31 that allows the solution to spray out of spray jets 103 . No pump is needed to spray the solution as the invention utilizes water pressure provided at the faucet. This feature helps reduce the weight, cost, and complexity of device 100 . A tube 68 is provided for allowing electrical wires and hoses to pass through a wastewater tank 38 .

[0044] Device 100 includes a number of innovations that allow it to use less water and cleaning chemicals during cleaning operations. The bottom surface of device 100 is provided with an air duct 69 for directing exhaust air from a vacuum compressor and motor 7 forward towards an agitator 33 . Preferably, air duct 69 directs exhaust air across substantially the length of agitator 33 . As streams of solution exit jets 103 , the solution collides with the turbulent exhaust air thereby dispersing the solution. The streams of solution also are directed towards agitator 33 . As the solution strikes agitator 33 , which is normally rotating, the solution is further dispersed.

[0045] The dispersed solution allows the solution to soak into the fibers of material 50 faster than would otherwise be possible. This results in a number of advantages including the following:

[0046] Less water and cleaning chemicals are needed to clean the material;

[0047] Device 100 does not need to remove as much solution from the material, which allows the device to be smaller, lighter, and less expensive; and

[0048] The backing of the material does not become saturated with water, which allows the material to dry faster, prevents mildew, and prolongs the life of the material.

[0049] Agitator 33 is adapted to rotate on the bottom of device 100 where the agitator is in contact with material 50 . In the preferred embodiment, a drive motor 135 and chain drive 134 are provided for driving agitator 33 so that the lower portion of the agitator moves from back to front relative to device 100 .

[0050] As seen in FIG. 3 , agitator 33 comprises a substantially cylindrical spindle 35 and a plurality of flexible loops or fins 34 . Spindle 35 is adapted to rotate around a central axis. Loops 34 are preferably made of a flexible material, such as nylon or other synthetic materials that allow the loops to absorb impacts with hard objects. Loops may be a continuous fiber that is sewn into spindle 35 . In the preferred embodiment, two helical rows of loops 34 are attached to spindle 35 . However, a greater or lesser number of rows may be used and the rows may be straight. Alternatively, loops 34 may have a solid center portion 116 . Thus, loops 34 may be substantially planar fins. Loops 34 with solid center portion 116 may have the advantage that they are less expensive to manufacture and are more wear resistant.

[0051] Flexible loops 34 are a significant improvement over prior art agitating brushes because the loops will not tear or damage the fibers in carpets as brushes tend to do. Carpets are made up of tufts of fibers that are bond to a carpet backing. As the bristles of brushes move over a carpet, they are inserted into and pass through the tufts of fibers in a rake-like action. This action tends to tear and separate the fibers in the tufts. Brushes also force the fibers flat against the carpet backing. This applies stress to the fiber ends that may cause fibers to separate from the backing.

[0052] Loops 34 do not suffer from these problems because the loops move past the tufts and do not penetrate the tufts. Loops 34 comprise a leading edge that is wider than the leading edge of brush bristles. Loops 34 also have a rounded profile that does not catch on carpet fiber loops. These characteristics allow loops 34 to message tufts rather than rake the tufts.

[0053] Loops 34 are also self-cleaning. Brushes tend to get clogged with hair, carpet fibers, and other debris, especially when the carpet is wet. Flexible loops 34 , on the other hand, have less surface area upon which debris may rest. Consequently, loops 34 seldom become clogged or bound by debris.

[0054] The present invention does not require a height adjustment mechanism to adjust the height of the agitator as is required with brush agitators. The height of brush agitators must be adjusted to prevent deep penetration of carpet tufts. If the height is not properly adjusted, a brush agitator will quickly destroy a carpet by ripping fibers out of the backing. Loops 34 of agitator 33 go through carpets without penetrating the tufts of the carpet fibers. Therefore, agitator 33 will not destroy the carpet if it is not adjusted to a proper height.

[0055] The agitator of the present invention is also very effective at cleaning chemical laden carpets. Many carpet cleaning devices use excessive amounts of cleaning chemicals or they use chemicals that leave a heavy residue. After several cleanings with these chemicals, a crusty layer of hardened chemicals tends to accumulate in the backing and fibers of the carpet. Unlike brush agitators, agitator 33 of the present invention provides enough rigidity to break up and loosen the hardened chemicals without damaging the carpet.

[0056] Another advantage of agitator 33 is that it is not required to rotate at high speeds. In the preferred embodiment, agitator 33 rotates at 850 revolutions per minute. This is substantially slower than many prior art brush agitators. The slower speed helps prevent damage to materials and does not require a large drive mechanism. A smaller drive mechanism allows device 100 to be smaller, lighter, and less expensive than prior art devices.

[0057] As seen in FIG. 4 A, flexible loops 34 may be attached to spindle 35 at an angle to the direction of rotation 52 . In other words, the mounting angle or angular orientation of each loop 34 may not be in line with the direction of rotation. This angular orientation produces a greater agitating action in fibers of carpet 50 as the tufts of fibers are forced to move along the side of each loop 34 . In addition, each row of loops may have a different angular orientation. For example, a first row of loops 54 may be angled to the left of direction of rotation 52 and a second row of loops 56 may be angled to the right of direction of rotation 52 . This alternating angular orientation further enhances the agitating action of agitator 33 as the fibers in the carpet are vibrated in two directions. Alternatively, as seen in FIG. 4 B, first row of loops 54 may be aligned with the direction of rotation 52 with no angular orientation and second row of loops 56 may have an angular orientation.

[0058] Returning to FIG. 3, a plurality of squeegee elements 37 may also be provided on spindle 35 for squeezing water and soil out of material 50 as agitator 33 rotates. This allows device 100 to remove more wastewater more quickly than prior art agitating devices. Having less liquid in material 50 allows the material to dry more quickly.

[0059] Agitator 33 may also be used on a variety of cleaning equipment. Carpet cleaning devices, vacuums, and other devices utilize agitators. These devices may be easily adapted to utilize agitator 33 of the present invention to benefit from its many advantages.

[0060] It has been found that prior art agitators have a tendency to become wound or entangled with large amounts of hair, animal fur, and other fibers that decrease the efficiency of the agitators. Returning to FIGS. 1 and 2 , the present invention reduces this problem by providing a blade 102 in close relative proximity to agitator 33 . Blade 102 comprises a sharp edge that cuts long fibers as agitator 33 rotates. Preferably, blade 102 is substantially ⅛ ^th of an inch away from agitator loops 34 to prevent impacts between the loops and the blade. Blade 102 preferably has a serrated edge but a smooth edge may also be used.

[0061] The present invention also includes side rails 108 that are located on each side of agitator 33 . Side rails 108 slide on top of carpet 50 and maintain agitator 33 a predetermined height above the floor. This prevents agitator 33 from being damaged by hard objects that are below the predetermined height.

[0062] An inlet duct 101 is provided for removing wastewater, soil, and debris. A rear lip 39 of the opening of duct 101 is preferably 20 thousandths of an inch above the floor and a front lip 60 of the opening of duct 101 is in contact with the floor. A negative pressure is created by vacuum motor 7 which draws water and debris out of carpet 50 upwards through duct 101 .

[0063] Carpet cleaning devices often encounter heavy suds or foam that are caused by the residue of prior carpet cleaning operations. Many prior art carpet cleaning devices use excessive amounts of cleaning chemicals or they use poor quality cleaning chemicals. This can leave a chemical residue in carpets. When the residue is loosened and dissolved, heavy suds may form in carpet cleaning devices. Heavy suds reduce the efficiency of vacuum motors and may lead to clogging and overheating.

[0064] Most prior art carpet cleaning devices require an operator of the device to manually spray de-foaming chemicals into the ducts and tanks of the device. The present invention solves the excessive suds problem by utilizing an automatic de-foaming device. When suds reach electrodes 9 and 10 , electricity is conducted between the electrodes that activates a solid state relay switch 26 . Switch 26 controls a solenoid valve 21 that is connected to a de-foaming chemical tank 22 . When valve 21 is open, the negative pressure created by vacuum motor 7 in inlet vacuum chamber 1 draws the de-foaming chemical through tube 121 , and nozzle 120 . Thus, suds are dissolved before going into basket 11 and tank 38 .

[0065] This de-foaming design is simpler, less expensive to manufacturer, and requires less maintenance because no pump is needed to dispense the de-foaming chemical. The design is also automatic which eliminates the need for the operator to activate the de-foaming device. This reduces the risk of an inattentive operator damaging device 100 from an overload of suds and it also provides more efficient use of de-foaming chemicals as only enough is dispensed to eliminate the suds present in duct 101 .

[0066] As wastewater and debris are vacuumed up duct 101 , they are drawn into a basket 11 with a disposable bag 23 . Bag 23 comprises a plastic mesh or nylon that strains the wastewater and collects large debris. This prevents larger objects from falling into tank 38 where the objects may be ingested by a wastewater pump 20 . Basket 11 is perforated with holes 104 on the lower surfaces of basket 11 to allow water to drain from basket 11 . A plurality of holes 106 are provided in the upper surfaces of basket 11 to allow air to be vacuumed from basket 11 . The design of basket 11 provides an efficient means for separating air, wastewater and debris. The overall efficiency of device 100 is increased by efficiently separating and controlling the air, wastewater, and debris.

[0067] Preferably, basket 11 and may be removed from device 100 to enable an operator to remove and replace bag 23 . This is accomplished by pivoting basket 11 around a detachable hinge 114 . However, it is important that an adequate seal be provided when basket 11 is in place to prevent substantial loss of vacuum pressure.

[0068] Once wastewater filters through bag 23 and basket 11 , it drains into tank 38 . Tank 38 is provided with electrodes 24 and 61 . When the water level in tank 38 contacts both electrodes 24 and 61 , an electrical circuit is completed which signals solid state relay switch 25 to activate wastewater pump 20 . The wastewater pump 20 pumps wastewater out through wastewater line 19 .

[0069] Once the water level in tank 38 looses contact with electrodes 24 and 61 , relay switch 25 deactivates wastewater pump 20 . A logic circuit may be provided for allowing pump 20 to operate for a predetermined interval before it is deactivated. This allows pump 20 to remove most of the water in tank 38 .

[0070] When pump 20 is deactivated, some amount of wastewater is preferably allowed to flow backwards through the pump to clear the pump of sand and other debris that could otherwise accumulate. This is an advance over prior art carpet cleaning devices that allow debris to accumulate in wastewater pumps. The accumulated debris causes wear that reduces efficiency and eventually causes the pump to fail. In the present invention, back flushing is accomplished by allowing gravity and vacuum pressure to pull some amount of wastewater back through pump 20 .

[0071] Once air has been vacuumed through basket 11 it passes through screen 62 , return vacuum chamber 12 , and return air tube 67 . The air is then forced through vacuum motor 7 and channeled down exhaust duct 110 towards duct 69 . A gap is provided between ducts 110 and 69 to allow air circulation. It has been found that gaps between ducts 69 and 110 induce turbulence and a negative pressure that draws air from the internal cavity of device 100 . This creates air circulation that cools the motors and electrical components.

[0072] In the preferred embodiment, skids 112 are provided on the rear surface of device 100 . Skids 112 provide structural rigidity that supports the rear surface of device 100 when subjected to vacuum pressure. Skids 112 also provide a surface upon which device 100 may slide when being pulled over a step.

SUMMARY

[0073] It may now be seen from the above description that the present invention provides a novel carpet cleaning device. The device comprises a number of components and features that provide a number of advantages and improvements over the prior art. For example, the present invention is smaller, lighter, and less expensive to manufacture than prior art carpet cleaning devices. The present invention is also less destructive to carpets and material, uses less water, and is able to remove more soil than prior art devices.

[0074] Although the description above contains many specifications, these should not be construed as limiting the scope of the invention but as merely providing illustrations of some of the presently preferred embodiments of this invention. Thus, the scope of the invention should be determined by the appended claims and their legal equivalents rather than by the examples given.