Rug and carpet cleaner

A mobile rug or carpet cleaner is provided with a support housing having front and rear wheels mounted so that the unit is tilted about the housing axis of the front wheels to engage and disengage a cleaning head with the carpet to be cleaned. The cleaner includes a fluid delivery system which provides fluid flow to the cleaning head, an auxiliary cleaning head and a spotter. The fluid delivery system utilizes a pump having an open conduit which continuously recycles cleaning fluid to a reservoir. The continuous recycle allows a solenoid valve in a line transporting fluid to the cleaning head spray nozzles to be abruptly closed without subjecting the entire fluid delivery system to a sudden, potentially damaging increase in fluid pressure. An automatic drain system utilizes a vacuum line to direct spent cleaning fluid to a removable waste tank for disposal. Suction can be selectively directed to the cleaning head or to the auxiliary head.

BACKGROUND OF THE INVENTION 
This invention generally relates to cleaning devices and specifically to 
cleaning devices for rugs and carpets. 
Most of the prior art devices for cleaning rugs and carpets have consisted 
basically of a system for delivering cleaning solution (usually a hot 
aqueous detergent solution) to the rug or carpet and a system for 
vacuuming the applied cleaning solution from the rug or carpet. Many of 
the prior art devices had rotating brushes or beater bars to work the 
cleaning solution into the rug or carpet and to aid in the dislodging of 
dirt and other debris from the fibers of the rug or carpet. 
The delivery system for the cleaning solution usually included a reservoir 
or tank for holding the solution, a pump for pumping solution from the 
tank to a cleaning head having one or more nozzles to apply the cleaning 
solution onto an underlying rug or carpet to be cleaned. 
The vacuum system generally comprised a vacuum chamber or nozzle disposed 
in the cleaning head which is positioned over the rug or cleaner to 
aspirate applied cleaning solution, dirt and other debris from the rug or 
carpet, and a vacuum pump in fluid communication with the vacuum chamber 
or nozzle to generate a partial vacuum therein. 
There are two variations of the basic system found in the marketplace. In 
one embodiment, the cleaning head, the solution delivery system, the 
vacuum system and one or more solution tanks are integrated into a single 
wheeled housing which is pulled over the rug or carpet by the operator. 
The other embodiment is similar to the first except that the cleaning head 
is a separate unit from a wheeled housing containing the vacuum system, 
the solution delivery system and the solution tanks. Vacuum tubes and 
solution delivery tubes are provided to interconnect the separate cleaning 
head with the respective vacuum and solution delivery systems in the 
wheeled housing. In this latter embodiment, the separate cleaning head is 
usually provided with an elongated, metal or rigid plastic vacuum tube 
connection which is used as a handle to facilitate movement of the 
cleaning head over the rug or carpet by the operator. 
Both embodiments have advantages and disadvantages. For example, the 
cleaning unit having a separate cleaning head is easier to manipulate over 
a rug or carpet surface during the operation thereof, but because of the 
additional distance the fresh solution must be pumped to the cleaning head 
and the spent solution must be transferred back to the housing after the 
aspiration thereof from the rug or carpet, the power requirements for both 
the solution pump and the vacuum pump are substantially increased. 
Moreover, the connections for the tubings for the separate cleaning head 
present maintenance problems because they frequently leak solution. 
The cleaning devices which are completely contained in a wheeled housing 
are most desirable from a manufacturing and maintenance point of view but 
they are very difficult to move over a rug or carpet surface during the 
cleaning thereof. As a result of this latter difficulty in operating the 
integrated units, their use has been limited to professional or commercial 
rug and carpet cleaners. 
Both types of prior cleaning devies required frequent repair of leaking 
solution lines and connections due to the frequent abrupt application of 
high fluid pressure to the solution delivery lines during the operation of 
the cleaning unit. 
Additionally, although the prior cleaning devices which employed rotating 
brushes or beater bars in the cleaning head provided improved cleaning, 
they caused very rapid wear of the rug and carpet fibers. 
The present invention is directed to improvements in the rug and carpet 
cleaning devices. More specifically, the invention responds to the need to 
make cleaning devices easier to manipulate during use thereof and the need 
to make such cleaning devices more efficient in their operation and less 
costly to build and maintain. 
SUMMARY OF THE INVENTION 
The present invention is directed to an improved rug and carpet cleaner and 
particularly such a cleaning unit wherein a cleaning head, a cleaning 
solution delivery system, a tank for holding the cleaning solution and 
vacuum system for removing the applied solution from the rug or carpet are 
integrated into a wheeled mobile support housing. 
In accordance with the invention, the cleaning device is provided with 
front wheels on each side of the housing and at least one rear wheel 
disposed at the rear of the cleaning unit to support the cleaning device 
in a generally upright position. The two front wheels are mounted on a 
common axis of rotation which is disposed in front of or at least aligned 
with the center of gravity of the cleaning unit when the unit is in an 
upright position. However, when the cleaning unit is tilted forwardly 
about the axis of rotation of the front wheels so that the cleaning head 
engages the rug or carpet for cleaning, the axis of rotation is rearward 
of the center of gravity so that the cleaning unit remains in the tilted 
position during the cleaning process. 
The front wheels are mounted in a generally central location underneath the 
cleaning unit and such mounting of the front wheels results in a 
substantial frontal overhang of the housing which contains the cleaning 
head. The cleaner unit is easily moved into a desired location when it is 
in an upright position by rolling on both the front and rear wheels. When 
the unit is to be operated to clean rugs or carpets, it is tilted so that 
a cleaning head in the front overhang engages the rug or carpet and then 
it is pulled rearwardly rolling on the front wheels alone while the 
cleaning head contacts the rug or carpet surface. 
The fluid delivery system comprises a conduit which leads cleaning fluid 
from the container holding same to a pump which directs the fluid to one 
or more nozzles provided in the cleaning head. The spray nozzles apply the 
cleaning fluid to the rug or carpet. 
The vacuum system comprises a vacuum source or pump which is maintained in 
fluid communication through one or more conduits to a vacuum chamber or 
nozzle in the cleaning head. Preferably, a sealed container is provided in 
fluid communication with the conduit leading from the vacuum chamber to 
the vacuum source wherein the spent cleaning solution is separated along 
with dirt and other debris from the carrier air stream. 
The invention also includes the utilization of an oscillating brush for 
working the cleaning solution into the rug and dislodging dirt and debris 
therefrom to enhance the cleaning thereof without causing undue wear or 
damage to the carpet fibers. The brush, which is preferably located in the 
cleaning head, oscillates through an angle less than about 90.degree. at a 
frequency between about 10 to 120 Hz. 
Furthermore, the invention includes a conduit for recirculating the 
cleaning solution from the pump back to the reservoir or tank holding the 
solution in order to moderate the effects of the frequent and abrupt 
application of high pressure to the solution delivery system which can 
cause leaks in the solution pump seals and the connections between the 
tubing, elbows and the like of the system. The flow of cleaning solution 
in the conduit from the cleaning solution pump to the spray nozzles in the 
cleaning head is controlled by a solenoid valve therein which is 
preferably actuated by a switch on the handle on the cleaning unit. 
In accordance with other embodiments of the invention, an auxiliary 
cleaning head is provided having a solution delivery line to direct 
solution from the cleaning solution pump to the auxiliary cleaning head 
and a vacuum line to direct spent cleaning solution aspirated from the rug 
or carpet by the auxiliary head to the vacuum system. A hand operated 
spray nozzle in fluid communication is also provided which is supplied 
with cleaning solution to apply cleaning solution to areas of the rug or 
carpet which need additional cleaning solution. By controlling the flow of 
cleaning solution to the main cleaning head by a solenoid valve, the 
solution lines to the auxiliary cleaning head and the spotting unit can be 
maintained under pressure during normal operation of the cleaner so they 
are available for immediate use. 
These and other advantages of the invention will become more apparent from 
the following detailed description of the invention and the accompanying 
exemplary drawings.

In all of the aforesaid drawings, corresponding parts are numbered the 
same. For purposes of clarity, the sectional views do not strictly follow 
the section lines indicated. Deviations from the section lines were taken 
so that the internal components of the cleaner would not have to be shown 
in section. 
DETAILED DESCRIPTION OF THE INVENTION 
Reference is made to FIGS. 1, 4 and 7 which illustrate a rug and carpet 
cleaning device 10 which embodies features of the invention. The cleaning 
device 10 comprises a mobile support housing generally shown at 11, a 
cleaning head 12, handles 13, front wheels 14 and rear wheels 15. A 
removable tank 16 is provided in the upper portion of the housing 11 for 
collecting used or spent cleaning solution. A handle 17 is provided on the 
tank to facilitate removal and handling. A tank top 18 is provided to 
close off the upper open end of tank 16 which is maintained under a 
partial vacuum during the operation of the cleaning apparatus. An 
elastomeric seal 19 is disposed between the top 18 and the upper edge of 
tank 16 to ensure maintenance of the partial vacuum in the tank. The top 
18 is pivotally mounted to the vacuum system conduits 23 and 24 and has 
sight glasses 21 and 22. Conduit 23 connects the tank 16 with a vacuum 
source 31, whereas conduit 24 leads an air stream which is entrained with 
spent cleaning solution to the tank where it is separated therefrom. Tank 
25 disposed partially underneath tank 16 contains unused cleaning solution 
which is to be applied to the rug or carpet. Electric cable 26 provides 
the appropriate electrical power to the electrical devices of the cleaning 
unit. Switches 27 and 28 are located on panel 29. Switch 27 operates an 
oscillatory brush 30 in the cleaning head 12, and switch 28 operates both 
the vacuum source 31 and the cleaning solution pump 32. Switch 33 mounted 
on the handle 13 actuates a solenoid valve 34 which controls the flow of 
cleaning solution from tank 25 to the spray header 35. 
An auxiliary cleaning head 36 is provided with the cleaning unit 10 and is 
operatively connected thereto by vacuum tube 37 and cleaning solution tube 
38. The auxiliary head 36 is operated by the hand actuated switch 39 
located on the underside of the head. 
The engagement of the cleaning head 12 with a rug or carpet 40 is best 
shown in FIGS. 2 and 3. FIG. 2 illustrates the cleaning unit 10 in a 
upright position resting on both the front and rear wheels 14 and 15 
respectively. The arrow 41 illustrates the normal direction of travel for 
non-operating movement. The FIG. 3 illustrates the cleaning unit 10 in a 
tilted position wherein the cleaning unit 10 has been rotated about the 
axis of rotation on which the front wheels 14 are mounted. The arrow 42 
shows the normal direction of travel. The center of gravity is indicated 
by circle 43. As is evident in FIG. 2 when cleaner 10 is in the upright 
position the axis of rotation of the front wheels 14 is forward of the 
center of gravity 43, whereas, when in the tilted position, as shown in 
FIG. 3, the axis of rotation is rearward of the center of gravity. As 
shown in FIG. 2, the cleaning unit 10 in the upright position can be 
easily moved to a desired location on both the front wheels 14 and rear 
wheels 15. When the cleaning function is desired, the unit 10 is tilted 
about the axis of the front wheels 14 so that the cleaning head can engage 
the rug or carpet. In this mode the cleaner 10 is pulled backwardly during 
the cleaning operation with the unit pulling on the front wheels 14 alone. 
As is evident, the resultant moment on the cleaning unit 10 due to the 
pulling on the handles 13 during the cleaning operation must not be so 
great that the cleaning unit 10 is pulled back onto the upright position. 
The cleaning solution delivery system is best shown in FIGS. 4, 5 and 6. 
This system includes a conduit 45 which is connected to the lower part of 
the reservoir 25 to transfer cleaning solution from the reservoir to the 
cleaning solution pump 32 which pumps the solution through conduit 46 to 
the spray header 35 located adjacent the cleaning head 12. Spray header 35 
directs the cleaning fluid to nozzles 52 which spray the solution onto the 
rug or carpet 40. Conduit 45 is also maintained in fluid communication 
with conduit 47 which directs cleaning solution to a spotting unit 48 and 
with conduit 38 which directs cleaning solution to the auxiliary cleaning 
head 36 by means of four way connector 49. Solenoid valve 34 in conduit 46 
controls the flow of fluid to the spray header 35. 
The cleaning head 12 as illustrated in FIGS. 4, 5, 7 and 11, has two 
chambers, a first vacuum chamber or nozzle 50 at the front end of the 
cleaning head 12 for aspirating cleaning fluid from the rug or carpet 40 
which has been sprayed thereon and a second spray chamber 51 rearward of 
the vacuum chamber 50 which has one or more spray nozzles 52 in fluid 
communication with spray header 35 for directing cleaning fluid onto 
underlying rug or carpet 40. An oscillating brush 30 is also pivotally 
mounted in spray chamber 51 for working cleaning solution into the fibers 
of the rug or carpet 40 in a gentle manner so that there is little damage 
or wear thereto. 
The vacuum chamber or nozzle 50 is in fluid communication with the vacuum 
system by means of a conduit 54 which passes through the spray chamber 51 
and which is connected to conduit 56 of the vacuum system. 
As best illustrated in FIGS. 4 and 7, the cleaning solution pump 32 is 
provided with a recirculating conduit 55 at the discharge end thereof 
which is in fluid communication with the tank or reservoir 25 containing 
unused cleaning solution. In this manner, while the solution pump 32 is 
operating, cleaning solution is continuously recirculated back to the 
holding tank or reservoir 25. Because the pump operates continuously, 
cleaning solution is always available under pressure to the spotting unit 
48 and the auxiliary cleaning head 36. Moreover, because of the 
recirculating line 55 the operation of the solenoid valve 34 in line 46 
does not subject the entire fluid delivery system to the sudden increase 
in fluid pressure which can damage lines and cause leaks in connectors and 
in pump seals. As shown in FIGS. 4 and 5, the solenoid valve 34 is 
supported from the bracket 53 bolted to a support frame which is part of 
the support housing 11. 
The vacuum system as best illustrated in FIGS. 5, 7 and 9-11 includes a 
vacuum source or pump 31 which establishes a partial vacuum in container 
16 through conduits 23 and 59. The partial vacuum established in container 
16 draws in air through conduits 24, 54 and 57 with conduit 54 being 
connected to the vacuum chamber or nozzle 50 located in the cleaning head 
12. The partial vacuum generated in the vacuum nozzle 50 aspirates 
cleaning solution which has been sprayed onto the rug or carpet through 
spray nozzles 52 and dirt and other debris from the rug or carpet 40 as 
shown by the arrow in FIG. 11, and is carried by the aspirating air stream 
to the tank 16 where the used or spent cleaning solution is separated from 
the air stream. The air stream pulled through the vacuum system by the 
vacuum pump 31 is discharged through conduit 58 shown in FIG. 10. 
As indicated in FIGS. 9 and 11, the vacuum line 37 to the auxiliary 
cleaning head 36 is connected to the vacuum system by means of a swing 
valve 60. The handle 61 thereof is rotated clockwise so that the end of 
the vacuum conduit 24 is in alignment and in fluid communication with 
elbow 62 which in turn is attached to and in fluid communication with 
vacuum line 37 of the auxiliary cleaning head 36. To return the vacuum 
system to the vacuum nozzle 50 in the cleaning head 12, the handle 61 is 
rotated counterclockwise to align the end of vacuum conduit 56 with the 
elbow 63 which in turn is interconnected with the vacuum conduit 57. 
The operation of the oscillating brush 30 is shown in FIGS. 5 and 8. The 
brush 30 having bristles 65 thereon is fixed to a bar 67 which is 
journaled at each end thereof to bearings 68 and 69 on the inside surface 
of spray chamber 51 in the cleaning head 12. Drive arm 70 is pivotally 
connected at one end thereof to bracket 71 fixed to the bar 67 and 
pivotally connected at the other end thereof to the drive wheel 72. The 
end of drive arm 70 is mounted off-center on the drive wheel 72 so that 
reciprocating motion of the drive arm 70 results when the drive motor 73 
rotates the drive wheel 72. The angular movement of the brush 30 about the 
axis of bar 67 should not exceed 45.degree. from the vertical, i.e., a 
total angle of oscillation not greater than 90.degree.. Additionally, the 
oscillating frequency may range up to about 28 Hz. Oscillation frequencies 
much greater than 28 Hz and angular movements greater than 45.degree. from 
the vertical tend to cause excessive wear to the rug or carpet fibers. The 
brushing element 30 gently works the cleaning solution into the fibers of 
the rug or carpet 40 and aids in dislodging dirt and other debris from the 
fibers so that the partial vacuum in the vacuum nozzle 50 can aspirate 
both the cleaning solution and the dislodged dirt and other debris. 
The electronic circuit for controlling the brush motor 23, the vacuum pump 
or blower 31, cleaning solution pump 32 and the solenoid valve 34 is shown 
in FIG. 12. The power source 74 may be a conventional 115 volt AC soure. 
Electric power cable 26 comprises conductors 76 and 77 which direct the 
elecrical power to the brush motor 73, the vacuum source or pump 31, the 
cleaning solution pump 32 and solenoid valve 34. Switch 27 activates the 
brush motor 73, whereas switch 28 actuates both the vacuum pump 31 and the 
cleaning solution pump 32. Switch 33 activates the solenoid valve 34. The 
indicating light 75, which is located on the panel 29 indicates when lit 
that the solenoid valve 34 is open and cleaning solution is flowing to the 
spray nozzles 52 in the cleaning head 12. Only the brush motor 73 and the 
cleaning solution pump require fuses as shown respectively at 78 and 79. 
To operate the cleaning device of the invention, the unit is pushed in an 
upright position to a desired location. Switch 28 is actuated to operate 
the vacuum and fluid delivery systems and switch 27 is actuated to operate 
the oscillating brush 30. The cleaner unit 10 is tilted about the axis of 
rotation of the front wheels 14 so the cleaning head 12 can engage the rug 
or carpet 40. Switch 33 on handle 13 is actuated by the operator to open 
up the solenoid valve 34 to allow cleaning solution to pass through line 
46 from tank 25 to the spray header 35 where the solution is applied to 
the rug or carpet 40 through spray nozzles 52. While the cleaning unit 10 
is pulled along the rug backwardly in the tilted position, cleaning 
solution is sprayed onto the rug 40 and worked into the carpet by brush 30 
and then the cleaning solution is removed from the rug along with the dirt 
and other debris which is dislodged therefrom by the vacuum nozzle 50. As 
needed, tank 25 is filled with fresh cleaning solution and tank 16 is 
removed from the housing 11 so that spent cleaning solution therein can be 
discarded. The cleaning solution is preferably a hot aqueous detergent 
solution although other aqueous and non-aqueous cleaning fluids can be 
used. 
It is obvious that modifications can be made to the present invention 
without departing from the scope thereof. For example, the cleaning device 
of the invention is described herein in terms of a rug and carpet cleaner; 
however, the device can be used to clean a variety of surfaces.